<DOC>
[107th Congress House Hearings]
[From the U.S. Government Printing Office via GPO Access]
[DOCID: f:84699.wais]
MERCURY IN DENTAL AMALGAMS: AN EXAMINATION OF THE SCIENCE
=======================================================================
HEARING
before the
COMMITTEE ON
GOVERNMENT REFORM
HOUSE OF REPRESENTATIVES
ONE HUNDRED SEVENTH CONGRESS
SECOND SESSION
__________
NOVEMBER 14, 2002
__________
Serial No. 107-159
__________
Printed for the use of the Committee on Government Reform
Available via the World Wide Web: http://www.gpo.gov/congress/house
http://www.house.gov/reform
------
84-699 U.S. GOVERNMENT PRINTING OFFICE
WASHINGTON : 2003
____________________________________________________________________________
For Sale by the Superintendent of Documents, U.S. Government Printing Office
Internet: bookstore.gpr.gov Phone: toll free (866) 512-1800; (202) 512ÿ091800
Fax: (202) 512ÿ092250 Mail: Stop SSOP, Washington, DC 20402ÿ090001
COMMITTEE ON GOVERNMENT REFORM
DAN BURTON, Indiana, Chairman
BENJAMIN A. GILMAN, New York HENRY A. WAXMAN, California
CONSTANCE A. MORELLA, Maryland TOM LANTOS, California
CHRISTOPHER SHAYS, Connecticut MAJOR R. OWENS, New York
ILEANA ROS-LEHTINEN, Florida EDOLPHUS TOWNS, New York
JOHN M. McHUGH, New York PAUL E. KANJORSKI, Pennsylvania
STEPHEN HORN, California PATSY T. MINK, Hawaii
JOHN L. MICA, Florida CAROLYN B. MALONEY, New York
THOMAS M. DAVIS, Virginia ELEANOR HOLMES NORTON, Washington,
MARK E. SOUDER, Indiana DC
STEVEN C. LaTOURETTE, Ohio ELIJAH E. CUMMINGS, Maryland
BOB BARR, Georgia DENNIS J. KUCINICH, Ohio
DAN MILLER, Florida ROD R. BLAGOJEVICH, Illinois
DOUG OSE, California DANNY K. DAVIS, Illinois
RON LEWIS, Kentucky JOHN F. TIERNEY, Massachusetts
JO ANN DAVIS, Virginia JIM TURNER, Texas
TODD RUSSELL PLATTS, Pennsylvania THOMAS H. ALLEN, Maine
DAVE WELDON, Florida JANICE D. SCHAKOWSKY, Illinois
CHRIS CANNON, Utah WM. LACY CLAY, Missouri
ADAM H. PUTNAM, Florida DIANE E. WATSON, California
C.L. ``BUTCH'' OTTER, Idaho STEPHEN F. LYNCH, Massachusetts
EDWARD L. SCHROCK, Virginia ------
JOHN J. DUNCAN, Jr., Tennessee BERNARD SANDERS, Vermont
JOHN SULLIVAN, Oklahoma (Independent)
Kevin Binger, Staff Director
Daniel R. Moll, Deputy Staff Director
James C. Wilson, Chief Counsel
Robert A. Briggs, Chief Clerk
Phil Schiliro, Minority Staff Director
C O N T E N T S
----------
Page
Hearing held on November 14, 2002................................ 1
Statement of:
Haley, Boyd E., professor and chair, Department of Chemistry,
University of Kentucky, Lexington, KY; G. Mark Richardson,
director and risk assessment specialist, Risklogic
Scientific Services, Inc., Ottawa, Canada; Richard D.
Fischer, past president of International Academy of Oral
Medicine and Toxicology; J. Rodway Mackert, professor of
oral rehabilitation, Medical College of Georgia Dental
School, Athens, GA, on behalf of the American Dental
Association; Gregory Stoute, president, National Dental
Association, Cambridge, MA; and Michael Bender, director,
Mercury Policy Project, Montpelier, VT..................... 25
Tabak, Lawrence A., Director, National Institute of Dental
and Craniofacial Research, National Institutes of Health,
Bethesda, MD; and Dr. David W. Feigal, Director, Center for
Devices and Radiological Health, Food and Drug
Administration, Rockville, MD.............................. 108
Letters, statements, etc., submitted for the record by:
Bender, Michael, director, Mercury Policy Project,
Montpelier, VT, prepared statement of...................... 88
Burton, Hon. Dan, a Representative in Congress from the State
of Indiana, prepared statement of.......................... 5
Feigal, Dr. David W., Director, Center for Devices and
Radiological Health, Food and Drug Administration,
Rockville, MD, prepared statement of....................... 118
Fischer, Richard D., past president of International Academy
of Oral Medicine and Toxicology, prepared statement of..... 47
Haley, Boyd E., professor and chair, Department of Chemistry,
University of Kentucky, Lexington, KY, prepared statement
of......................................................... 29
Mackert, J. Rodway, professor of oral rehabilitation, Medical
College of Georgia Dental School, Athens, GA, on behalf of
the American Dental Association, prepared statement of..... 56
Richardson, G. Mark, director and risk assessment specialist,
Risklogic Scientific Services, Inc., Ottawa, Canada,
prepared statement of...................................... 37
Stoute, Gregory, president, National Dental Association,
Cambridge, MA, prepared statement of....................... 83
Tabak, Lawrence A., Director, National Institute of Dental
and Craniofacial Research, National Institutes of Health,
Bethesda, MD, prepared statement of........................ 110
Watson, Hon. Diane E., a Representative in Congress from the
State of California, prepared statement of................. 12
MERCURY IN DENTAL AMALGAMS: AN EXAMINATION OF THE SCIENCE
----------
THURSDAY, NOVEMBER 14, 2002
House of Representatives,
Committee on Government Reform,
Washington, DC.
The committee met, pursuant to notice, at 11:13 a.m., in
room 2154, Rayburn House Office Building, Hon. Dan Burton
(chairman of the committee) presiding.
Present: Representatives Burton, Gilman, Otter, Norton, and
Watson.
Also present: Representatives Norwood, Simpson, and Linder.
Staff present: Kevin Binger, staff director; David A. Kass,
deputy chief counsel; S. Elizabeth Clay and John Rowe,
professional staff members; Blain Rethmeier, communications
director; Allyson Blandford, assistant to chief counsel; Robert
A. Briggs, chief clerk; Robin Butler, office manager; Joshua E.
Gillespie, deputy chief clerk; Nicholis Mutton, deputy
communications director; Susie Schulte, legislative assistant;
Mindi Walker, staff assistant; Corinne Zaccagnini, systems
administrator; Sarah Depres, minority counsel; Ellen Rayner,
minority chief clerk; and Jean Gosa and Earley Green, minority
assistant clerks.
Mr. Burton. Good morning. A quorum of the committee being
present, the Committee on Government Reform will come to order.
I ask unanimous consent that all Members' and witnesses'
written and opening statements be included in the record. And
without objection, so ordered.
I ask unanimous consent that all articles, exhibits, and
extraneous or tabular material referred to be included in the
record. And without objection, so ordered.
I ask unanimous consent that Congressman Norwood, Linder,
and Simpson, who are not members of the committee, be permitted
to participate in today's hearing. Without objection, so
ordered.
Sorry I am a little bit late. I appreciate all of you being
here.
Over the last 3 years, the Government Reform Committee has
looked at health and safety issues related to mercury-
containing products.
In July 2000, we held a hearing entitled, ``Mercury in
Medicine--Are we Taking Unnecessary Risks?'' We focused on why
mercury is put into vaccines that are given to children. We
received a report during that hearing that indicated that the
symptoms of mercury toxicity are similar to the symptoms of
autism.
That was followed up by a hearing on April 18, 2002,
entitled, ``The Autism Epidemic--Is the NIH and CDC Response
Adequate?''
We found out during our investigations over the past
several years that to our knowledge there has never been a real
test of whether or not thimerosal and mercury in vaccines is a
problem. In the 1920's, when they first started using
thimerosal, which contains mercury and is used as a
preservative, it was tested on I think twenty-some people who
had meningitis, all of whom died, and because they didn't die
or have any reactions to the thimerosal before they died, they
said that it really did not have any adverse effect and it was
a good preservative.
To my knowledge, there has never been any blind study,
double blind study, or anything else done on thimerosal or
mercury in vaccines since the 1920's. If that is the case, and
we believe it is, that is a real failure of our health agencies
because that should have been checked out.
We have conducted numerous hearings on the Vaccine Injury
Compensation Program. I am pleased that Dr. Dave Weldon and our
ranking minority member, Congressman Waxman, joined me in co-
sponsoring legislation to improve the compensation program. I
believe through our oversight activities that we have made it
absolutely clear to the Department of Justice and the
Department of Health and Human Services that the intent of
Congress was and remains that the National Vaccine Injury
Compensation Program should be a no-fault compensation program,
not a contentious tort system. I really regret that we have not
been able to get this bill passed because it would really help
a lot of people, and there are an awful lot of people who have
suffered who have not been compensated because of vaccine
related injuries.
Today's hearing will focus primarily on the science
regarding mercury-containing dental amalgams.
Early in our investigation, I was accused of being ``anti-
vaccine.'' Now that we are examining the science behind the use
of mercury in dental amalgams, I suppose I will be
characterized as anti-dentistry. And after all the money I have
spent on my teeth, that cannot be the case. [Laughter.]
Neither charge could be further from the truth.
Immunizations have been portrayed as one of the greatest
advances in public health during the past century, second only
to clean water and improved hygiene. I think that is true,
although we need to make sure that vaccines are as safe as
possible. I am for vaccines, I am for good dentistry, but we
want to make sure we are not putting toxic chemicals into our
bodies and into our children. Dentistry is a noble profession
that has contributed to Americans' overall health and quality
of life. While immunizations may offer a great benefit, they
also carry risks. And while dentistry offers great benefit, the
continued use of a toxic substance such as mercury needs to be
examined.
Mercury is mercury, whether it is methyl or ethyl, organic
or inorganic. There is no one in this room or in all of science
who can say with any level of credibility that any form of
mercury is safe. While many people have absolutely no problem
with being injected with thimerosal-containing vaccines, and
while mercury-containing dental amalgams have been used for
over 150 years, we have a responsibility to protect those who
are pregnant women, infants and young children, those who have
autoimmune dysfunction, and the elderly.
And with dental amalgams, I am also talking about
economically disadvantaged people of all ages who depend upon
Medicaid for dental care. They either get fillings with
mercury, or they get no fillings at all.
Are we giving them short-term relief by helping pay for
their dental work, only to set them up for disaster, for long
term problems down the road? We do not know.
The simple fact is that mercury is one of the most toxic
minerals on earth, second only to radioactive materials.
The fillings that typically are called ``silver'' fillings
because of their color probably should be called mercury
fillings. They consist of 50 percent or more of mercury. And a
lot of people do not even know that. When the mercury is mixed
with an alloy of powdered metals, it becomes Dental Amalgam.
For many years dental schools taught that when the amalgam
hardens it becomes inert. They taught that there was no further
risk from the mercury. However, from research, we now know that
mercury vapor continues to leech from amalgams for as long as
it remains in the mouth. The fumes are inhaled into the human
body and minute particles chip off and are ingested into the
stomach as fillings wear out.
This has important health implications, since mercury has a
long half-life and has the potential for doing significant
damage to the kidneys and brain. For reasons that are not well
understood, some individuals seem to hold on to the mercury
absorbed by their body, leaving them at risk for neurological
or renal damage.
In 1999 the U.S. Agency for Toxic Substances and Disease
Registry published the ``Toxicological Profile in Mercury.''
That was in 1999 that it was published. This report stated that
poisonous mercury vapors are constantly emitted from amalgam,
that these vapors go first to the brain, and that children are
most at risk because their brains are still developing. The
report further states that the mercury crosses the placenta
into the developing fetus, and that it is transmitted through a
mother's milk to the infant.
The Food and Drug Administration has taken what appears to
be a bipolar approach to protecting the public from mercury.
While denying that thimerosal in vaccines or mercury in dental
amalgams poses any health risk, it has taken a stand against
mercury in other products.
The FDA has repeatedly issued strong warnings cautioning
the public, and in particular pregnant women and young
children, to restrict their consumption of tuna and other fish
that is known to contain mercury.
The FDA has determined that mercury compounds used as
active ingredients in over-the-counter drug products were not
``generally recognized as safe.'' Mercurochrome had mercury in
it. When we were kids we used to put it on our skin to heal
wounds. It is a topical dressing. You cannot sell it anymore,
you cannot use it anymore because it has mercury in it and they
said it might leech through the skin and into the body and into
the brain. And yet we inoculate our kids with thimerosal in it,
and have for years, and we put metal amalgams into their
mouths.
They also have not approved any mercury-containing
compounds as food additives.
The FDA also states that lead, cadmium, and mercury are
examples of elements that are toxic when present at relatively
low levels.
I have asked before, and I will ask again, how is it that
mercury is not safe for food additives and over-the-counter
drugs but it is safe in our vaccines and in our dental
fillings?
There are alternatives to mercury-containing amalgams.
Shouldn't we exercise an abundance of caution and hasten the
use of these alternatives?
Before I conclude, I want to commend Congresswoman Diane
Watson of California for her initiative in sponsoring H.R.
4163, the Mercury in Dental Filling Disclosure and Prohibition
Act.
As I have already stated, the Federal Government must
exercise special care for vulnerable population groups.
Physical and in particular neurological damage from mercury is
an issue that crosses all boundaries--geographic, economic,
ethnic, religious, age, and gender--all boundaries.
It is said that you cannot stop an idea whose time has
come. Hasn't the time come for us to really examine this and
whether or not exposing people to mercury through medical
interventions is something that we should do away with.
I look forward to hearing from our witnesses today, to
learning about the scientific research that has been conducted
and to learn about what research still needs to be done.
The Record will remain open until November 28, 2002.
[The prepared statement of Hon. Dan Burton follows:]
[GRAPHIC] [TIFF OMITTED] T4699.001
[GRAPHIC] [TIFF OMITTED] T4699.002
[GRAPHIC] [TIFF OMITTED] T4699.003
[GRAPHIC] [TIFF OMITTED] T4699.004
Mr. Burton. I now recognize Ms. Watson for her statement,
and after that we will go to our guests.
Ms. Watson. Thank you so much, Mr. Chairman. I would like
to thank you for your leadership and your hard work on this
important issue. Above and beyond your diligence as chairman of
the Government Reform Committee, I applaud your vision and
compassion on public health issues. Your ability to reach
across the aisle and co-author H.R. 4163 is a tribute and is a
testimony to your dedication to, and your concern for the
public well being. I truly believe that elected public
officials are the stewards of public health. I also want you to
know that the importance of this issue is highlighted by your
decision to have this hearing before stepping down as Chair. So
thank you and your staff again. I look forward to this and
other work we will do together in the future.
As a former Chair of the California Health and Human
Services Committee for 17 years, I was given constant testimony
as to the status of Californian's health, especially those in
the lower socioeconomic sector of our population. In the
medical professions, including dentistry, professionals have
sworn to ``do no harm.'' Dentists have stood behind a long
history of utilizing mercury; however, a long history of use is
no excuse.
Mercury in any form is as much of a health risk as lead in
paint and asbestos. Mercury is being taken out of other health
care products as well as disinfectants, thermometers, childhood
vaccines, and even horse medicine. With mercury, a highly toxic
substance, as the main ingredient in dental amalgams, I can
only ask a very simple question--why take the risk?
In 1991 I wrote a law, Section 1648.10 of the California
State Business and Professions code, that mandated a fact sheet
be produced by the California State Dental Board stating the
risks as well as the efficacies of dental materials. Over the
next 9 years, the board did not comply. But I am pleased to see
that our Governor has installed a new California Dental Board.
For the first time in California history, the legislature
closed down a State board before its authorization time had run
its course.
Of biggest concern to me when I wrote the law was amalgam,
because it is composed of approximately 50 percent mercury, a
very pervasive and persistent toxic element. Mercury has been
placed on the list of reproductive toxic substances in
California's Proposition 65. I found that most consumers did
not know amalgam contained mercury, and it is easy to see why.
The filling is simply called ``silver'' by organized
dentistry--a very deceptive misnomer.
Mercury must be removed from the last known use in the
human body. Again I ask, why take the risk? Consumers have not
been informed about the differing properties of various dental
materials--for example, resin, gold, porcelain, and mercury
amalgam--and they have certainly not been told of the possible
risks to their health and the environment. The public has a
right to know. The public has a right to be informed and to
make choices.
Regrettably, the American Dental Association has a
provision in its code of ethics to stop dentists from
initiating communications with patients about the risks of
mercury dental fillings. I would say shame on them. This what I
call ``the gag rule'' has unfortunately been enforced by many
dentist-dominated State dental boards. I am happy to report
that yesterday the Iowa Dental Board repealed its gag rule, and
that earlier this year Oregon did likewise. The dental board in
my home State of California repealed its gag rule in 1999. It
is now time for the American Dental Association to stop
blocking communications from dentists informing their patients
about amalgam. It is time for every State dental board to stop
enforcing this gag rule and to do the right thing.
This current legislation, H.R. 4163, introduced by Chairman
Burton and I, is an extension of my California State disclosure
law. The bill has three main goals: One, to ban mercury amalgam
for children under 18, pregnant women, or nursing mothers,
effective immediately; two, dental disclosure and a health
warning for all consumers, effective immediately; and three, a
phase-out of all mercury amalgam use in the United States by
January 1, 2007.
The provisions of the bill reflect the fact that mercury
poses a particular risk to children, lactating and pregnant
women. The U.S. Agency for Toxic Substances and Disease
Registry states that poisonous mercury vapors are constantly
emitted from dental amalgams, that these vapors go first to the
brain, and that children are most at risk because their brains
are still developing. The report further states that mercury
can go through the placenta to the fetus, and through the
mother's breast milk to the infant. The two most common
occurrences of mercury toxicity in humans are from dental
amalgams and fish. It is time pregnant women learn as much
about the amalgam risks as they do the risks from mercury-laced
fish. The fact that mercury vapor is continually being emitted
from the mercury amalgam fillings is not disputed by anyone.
Again I ask, why take the risk?
There is a growing international movement in both
scientific and dental communities that now disapprove of
amalgam, and the government of Canada advised in 1996 against
its use for pregnant women, for children, and people with
kidney problems, orthodontic braces, or mercury allergies.
Indeed, the major manufacturer of amalgam warned back in 1997
that amalgam is contra indicated, meaning not to be used, for
those five vulnerable population categories. Sweden, Germany,
Austria, and now Norway have announced plans to go mercury-
free, and the U.K. says pregnant women should not get mercury
fillings.
What is happening in the United States? We hope that we
will see a movement starting with this bill, because mercury is
an environmental poison and listed as the No. 1 environmental
poison by the World Health Organizations.
I am very pleased to inform you that the National
Convention of the NAACP endorsed H.R. 4163. And I tell you how
significant that is, because I had a group of minority dentists
come to me and they said, ``How dare you scare people into
thinking that they do not want to come in because we are
putting poisons in their mouths.'' I said, ``You as medical
people, are you saying to me that you do not want to inform
your patients about what is in that amalgam, if there is a
risk? I do not understand, if you are sworn to do no harm.''
So to be able to convince the NAACP, and all these dentists
who are members, that there is a considerable threat to lower
socioeconomic people and people that they serve, because they
are the ones that go in and get the fillings and they are the
ones who are at risk and they should be able to know, and we
should be able to inform them, then they can make the choice.
The dentists said to me, ``Well, it is cheaper. You know,
people do not like to go to the dentist anyway.'' That does not
prevail. That is not a compelling argument when a person's
health is at risk. So we have the NAACP's endorsement, and I am
very, very pleased to announce that.
And last, the subject of the Food and Drug Administration
classification of dental mercury amalgam must be addressed. The
FDA must come forward and be open and honest with Americans.
And so we are hoping that this bill, Mr. Chairman, will be
a beginning. I look forward to the testimony that is going to
be presented here this morning. I am pleased to have the
opportunity to hear the scientific and regulatory testimony on
this issue. I think there is a lot to be learned, a lot to go
public, and a lot for Americans to consider.
So thank you for your leadership, and thank you to the
presenters. If I slip out for a moment, I have business in
another building but I will have heard your testimony. So thank
you, Mr. Chairman, for the opportunity.
[The prepared statement of Hon. Diane E. Watson follows:]
[GRAPHIC] [TIFF OMITTED] T4699.005
[GRAPHIC] [TIFF OMITTED] T4699.006
[GRAPHIC] [TIFF OMITTED] T4699.007
[GRAPHIC] [TIFF OMITTED] T4699.008
[GRAPHIC] [TIFF OMITTED] T4699.009
[GRAPHIC] [TIFF OMITTED] T4699.010
[GRAPHIC] [TIFF OMITTED] T4699.011
[GRAPHIC] [TIFF OMITTED] T4699.012
[GRAPHIC] [TIFF OMITTED] T4699.013
[GRAPHIC] [TIFF OMITTED] T4699.014
Mr. Burton. We will go next to Mr. Otter, who is a member
of the committee, and then we will go to our guests, Mr. Linder
and Mr. Norwood.
Mr. Otter. Thank you, Mr. Chairman. It had been my intent
when you offered me the microphone to defer to my colleagues,
all three of which are guests here in our committee room today.
But knowing that they are dentists, it does not bother me to
have the dentists wait on me for once. [Laughter.]
So I am going to go ahead. Dentists have used amalgam
fillings safely for over a century. As my dentist colleagues
can and will attest to, I believe, dentists have come to rely
on the use of amalgam as a harmless, dependable, and cost-
effective material with which to treat their patients. In fact,
numerous studies have already been conducted, apparently not
for the benefit of those who would wish to ban amalgam. An
assortment of health organizations, including the World Health
Organization, the U.S. Public Health Service, the Food and Drug
Administration has issued an opinion on this, the Center for
Disease Control and Prevention and National Health Institute,
all conducted and concluded that ``with the exception of rare
personal allergic reaction to amalgam components, there is no
evidence that the use of amalgam in dental fillings causes
consistent health problems in our population.''
Given these conclusions, H.R. 4163 simply fixes a problem
that does not exist, and therefore unnecessarily eliminates I
believe a very cost-effective treatment option for dentists and
for their patients.
The very function of the Department of Health and Human
Services is to protect our population from health risks. This
Congress and many Congresses before it continue to fund these
organizations. Why then does Congress ignore the research
studies and continue to second-guess and undermine the
conclusions of these very organizations that we fund?
This country enjoys the most accurate and comprehensive
state-of-the-art medical research institutions in the world. We
should heed the advice and conclusions of these health
professionals. The use of amalgams should remain a viable
option for dentists and for their patients. Simply put, Mr.
Chairman, I hope we are not pulling the wrong tooth here today.
Thank you.
Mr. Burton. Thank you, Mr. Otter.
Mr. Linder.
Mr. Linder. Nothing, Mr. Chairman.
Mr. Burton. No opening statement? Mr. Norwood.
Mr. Norwood. Thank you, Chairman. I would like to
particularly thank you for extending the courtesy of us
participating in today's hearing. I for one am very grateful
for this opportunity.
I practiced dentistry for 25 years and I have placed
thousands and thousands of dental amalgam restorations in my
patients. And you know what? If I have been hurting my
patients, I want to know about it. But I want to know about it
with good science. I want to know about it from people who are
trying to look at this issue for all the right reasons.
I have always known this material to be safe and effective
and safe for me. If you think my patients have been around
amalgam very much, I have been around it many, many greater
hours and times than any patients that I have. Now I will grant
you, there are some Members of Congress who might say that it
has affected me greatly. [Laughter.]
But my wife seems to think it is OK. And I want you to know
that I today believe it to be OK.
I am very worried about hearings like this and what it can
do to the dental health of the people of this Nation.
Misinformation is very, very dangerous. Those of us who have
been trying to serve our patients and improve the dental health
of this Nation and have been on the front line of this, the
greatest majority agree that this is a very safe restoration.
The reason we call it silver is very simple--it is silver. It
is not mercury. Mercury is toxic; I agree that it is toxic,
particularly in some doses. So is chlorine, but salt is not
deadly unless you inhale too much of it, I suppose. Mercury is
not the same thing as an amalgam. We need to make that very
clear in this hearing today.
We must put our emphasis on good peer reviewed science so
as to not harm our citizens and keep them away from seeking
dental care. I have spent my life trying to get patients to
come and be treated so that in this Nation we can have the best
dental care in the world. And this is not the way to go about
improving dental care in America. If we are going to take
action on the use of dental amalgam, we better be darn right or
we are going to affect a large part of our population's ability
to access care. And that should be very much part of our
concern here too.
Mr. Chairman, I look forward to this hearing more than I
can ever tell you. I am grateful for you allowing us to be
here. I yield back my time.
Mr. Burton. Thank you, Dr. Norwood.
Mr. Simpson, my buddy from Idaho.
Mr. Simpson. Thank you, Mr. Chairman. I, too, want to
extend my appreciation for allowing us to sit with your
committee today to explore this issue. And I also want to thank
you for actually holding this hearing on H.R. 4163. I
appreciate your sincere concern about this subject, and
Congresswoman Watson's concern about this subject. Even though
I am opposed to the bill, it is important to hold these
hearings I think to be able to put forth the science concerning
amalgam and other mercury-containing medical treatment.
Sometimes in this job, in fact most often in this job, we
react to public concerns. Sometimes we over-react to public
concerns. And let me say without equivocation that if there
were any credible and supportable evidence that amalgam was
unsafe to the patient, I am certain that the ADA, joined by Dr.
Norwood, Dr. Leonard, and myself, would immediately call for
its removal from the approved products list. I would also have
the amalgam fillings removed from my mouth, of which I have a
few.
What concerns me is some of the implication that was stated
during the testimony of Congresswoman Watson that somehow this
is a money issue with dentists, that they are less concerned
with their patients' health. I can assure you that is not the
case. I am not sure what she meant by stop enforcing these
board-enforced gag orders that prevent dentists from
communicating to their patients the effects of amalgam. I was
always free in the 22 years I practiced dentistry to
communicate whatever I wanted to to my patients. In fact, not
only was I free to do so, I had an obligation to communicate
with them the effects of the treatment that I was going to
render them. So I do not know what gag order she is
specifically talking about.
It is important to remember that mercury and amalgam, as
Dr. Norwood said, are not the same thing. Amalgam remains an
important restorative material in dentistry, and I think will
so in the future. Yes, we are developing other types of
restorative material. Those are not appropriate in all
circumstances and oftentimes amalgam is the best restorative
material that you can use in certain circumstances.
So I believe, as everyone has said, that our decisions, and
I am sure you would agree, should be based on science and not
over-reacting to public concern, while we should take public
concern into consideration. I do appreciate your holding these
hearings today so that we can put the science forward
concerning amalgam. Thank you.
Mr. Burton. Thank you.
We will now go to our witnesses. I would submit to my
colleagues who are dentists, the March 1999 study, I do not
know if you have seen that or not, does have some interesting
things that might be illuminating for you.
I would now like to call to the dais Dr. Boyd Haley, Ph.D.,
Professor and Chair of the Department of Chemistry, University
of Kentucky, Lexington, Kentucky; Dr. G. Mark Richardson,
Director and Risk Assessment Specialist, Risklogic Scientific
Services, Inc., Ottawa, Ontario, Canada; Dr. Richard D.
Fischer, a good friend of mine from Annandale, Virginia, past
President of the International Academy of Oral Medicine and
Toxicology; Dr. J. Rodway Mackert, Professor of Oral
Rehabilitation, Medical College of Georgia Dental School,
Athens, Georgia, who is here on behalf of the American Dental
Association, your colleagues; Dr. Gregory Stoute, Cambridge,
Massachusetts, President of the National Dental Association;
Mr. Michael Bender, Director of the Mercury Policy Project,
Montpelier, Vermont.
Would you all please stand and raise your right hands.
[Witnesses sworn.]
Mr. Burton. Be seated. We will start with you, Dr. Haley. I
would like to, since we have such a large number of witnesses,
I would like to have you confine your remarks to as close to 5
minutes as possible so we can get to questions, because I think
there is going to be an abundance of questions for all of you.
Dr. Haley.
STATEMENTS OF BOYD E. HALEY, PROFESSOR AND CHAIR, DEPARTMENT OF
CHEMISTRY, UNIVERSITY OF KENTUCKY, LEXINGTON, KY; G. MARK
RICHARDSON, DIRECTOR AND RISK ASSESSMENT SPECIALIST, RISKLOGIC
SCIENTIFIC SERVICES, INC., OTTAWA, CANADA; RICHARD D. FISCHER,
PAST PRESIDENT OF INTERNATIONAL ACADEMY OF ORAL MEDICINE AND
TOXICOLOGY; J. RODWAY MACKERT, PROFESSOR OF ORAL
REHABILITATION, MEDICAL COLLEGE OF GEORGIA DENTAL SCHOOL,
ATHENS, GA, ON BEHALF OF THE AMERICAN DENTAL ASSOCIATION;
GREGORY STOUTE, PRESIDENT, NATIONAL DENTAL ASSOCIATION,
CAMBRIDGE, MA; AND MICHAEL BENDER, DIRECTOR, MERCURY POLICY
PROJECT, MONTPELIER, VT
Mr. Haley. If I could have the first slide. We will go to
the science. This is what people are wanting to see. This is
research done where we looked at the mercury level in a birth
hair of babies, those that have become autistic and those that
are controls are normal. And if you look at this slide and you
look at the level, if you look at the top line that is
controls, and below that, on the abscissa of that is the number
of dental amalgams that the birth mother had. And in control
children, you see an elevation in the birth hair with
increasing number of amalgam fillings. However, with the
autistics, the bottom line, no matter how many amalgam fillings
the mother has, they have less on average of about 0.5 parts
per million in their hair.
A reasonable interpretation of this is that autistic
children represent a subset of the population that cannot
effectively excrete mercury. One thing you cannot disagree with
is that autistics handle mercury different than children who
are born and who do not become autistic.
This slide shows the severity of the disease. As you go
across, as the level of mercury in parts per million in the
hair of these children decreases, the severity of the autism
increases. And what you will notice is the female to male
ratios are quite different in the different categories. On the
far left, where the mercury levels are on average higher, you
will see that the females almost all fall below the average
amount of mercury in their hair, whereas the males are in the
top and the females are roughly 50 percent. If you go to the
next one, you see the female population disappears, drops
dramatically. And as you go to the higher level, it is even
more pronounced. There is only one female in the severe autism
case. This fits into the situation where boys get the disease
about four to five times more often than girls and they are the
ones that get the severe cases of autism by far the most.
Could I have the next slide. If we look at the synergistic
toxicities, and this is my major disagreement with the dental
association, you cannot tell somebody what level of mercury is
safe. A person that is exposed to lead, or aluminum, or a
number of other things that is then exposed to mercury will
have a totally different reaction than that individual who is
not exposed, the same individual, if he were not exposed to
other toxic metals, etc.
The thing that is very interesting here--this is with
neurons in culture, the mammalian neurons, and the top line is
the control--if you look at the green, that is the one that is
critical, if we take testosterone, which has no effect on the
neurons when it is added alone, if you add it to a level of 15
nanomolar thimerosal, which takes several hours to kill the
neurons, it will kill all the neurons 100 percent in the first
time point. So, logically or reasonably speaking, the presence
of testosterone enhances the toxicity of ethyl-mercury from
thimerosal by over 100-fold. This fits into the data by Dr.
Barren Cohen in London where he measured the testosterone level
of the amniotic fluid of females that give birth to autistic
children, compared it to controls, and the one consistent
feature was that their amniotic fluid contained high levels of
testosterone, the highest levels.
So we have a gender risk factor here that is put in by a
hormone. I would also point out that estrogen has exactly the
opposite effect. It is protective. If we add estrogen to this
study, fewer of the neurons die out at 12 hours. And this fits
into the model where you see that people say women on estrogen
therapy are less likely to become demented with Alzheimer's
disease.
Could I have the next slide. This is the one that amazes me
that our Government, the American Medical Association, the
National Institutes of Health seem to totally ignore. This is a
disease called idiopathic dilated cardiomyopathy. This is young
athletes that drop dead during high school athletic events.
They have 22,000 times more mercury in their heart tissue. Most
of these kids are inner-city kids or kids from the countryside,
they are not people that eat shark, tuna, or mackerel. Where
does the mercury come from? And is it causal, or is it just a
happenstance? This needs to be addressed. If you want science,
why don't you have NIH go look at this.
Could I have the next slide. This is the fact about
neurons. If you take neurons in culture, you see significant
death at five nanomolar, 5 times 10 to the minus 9th molar,
that is roughly 100fold less than what you find in the brain of
the average person. They have concentrations around 10 to the
minus 7 molar, although it varies dramatically. So we can say
this compound mercury itself is extremely neurotoxic if it gets
into the brain and if you do not have the reducing equivalence
to effectively chelate and remove it by the natural process.
Could I have the next slide. This is the problem with
neurons.
The major protein in neurons is a protein called tubulin,
it is the one at the bottom, and it forms into something called
mycrotubuls, which you see at the very bottom. It is the major
protein in there and when one atom of mercury binds to one
molecule of tubulin, it disrupts that entire structure. Our
studies have shown that mercury mimics the effects that we see
in Alzheimer's disease. And so we are going to be talking about
this protein for just a few minutes.
Could I have the next slide. This is what we do with our
research, and I cannot explain photofendelabeling except to say
that NIH funded it for about 27 years in my laboratory and this
technique is used by NIH, Mayo Clinic, and everyone else that
do roughly the same thing that I do. When you look at an
Alzheimer diseased brain, you will find that on the average
about 80 percent of them have a dramatically lowered or totally
abolished photolabeling or viability of this protein called
tubulin. This is significantly found only in Alzheimer diseased
brain.
Could I have the next slide. When you take heavy metals,
all of them, we tested all of them, most of them are toxic but
if you chelate them with the normal compounds that exist in
your body, citrate, glutamate, or add EDTA, a common food
additive which is used to chelate and render heavy metals less
toxic, it stops the toxicity of every one of the heavy metals
except mercury and it makes the mercury more toxic. So we do
not have the level of protective compounds in our brain to
render mercury less toxic or non-toxic. It just does not work.
We did not evolve with any protective mechanisms except for
glutathione and metalthien, but definitely other compounds do
not work. And you will see that mercury exactly mimics the
profile that you see in an Alzheimer diseased brain and that it
does not affect the actin which is the bottom band below that.
Could I have the next slide. This is the take home lesson.
We have two controls on the right with zero mercury, it is not
all showing on your format here, and two Alzheimer diseased
subjects on the left. The bottom line is as you add low levels
of mercury--and you need to understand that this is done in a
test tube and it is done within a few minutes, it is not
letting it sit there for days, weeks, years at constant low
level exposure. You can make a control brain look like an AD
brain by the mere addition of mercury.
Could I have the next slide, please. This is an enzyme. We
published this in Molecular Brain Research called creatine
kinase in Alzheimer's diseased brain. It is over 97 percent
inhibited. I have done a lot of biochemistry on this, way
before the mercury issue ever came up, it has a very reactive
sulfur in the active site. If you take an amalgam filling, drop
it into distilled water, let it sit there, as we show here, 15
minutes, you see significant inhibition of the ability of that
enzyme to make creatine phosphate. So you cannot tell me that
breathing mercury vapor, having it going into your brain, if
you are a person that is going to become Alzheimer's diseased
is a good idea. It is a risk factor that we do not need to
take.
Could I have the next slide, please. This is the last
slide. If this were any other metal, it would have been kicked
out and named as a cause of Alzheimer's disease a long time
ago. It causes all the aberrant biochemistry, based on the
simple process it inhibits thyroreactive enzymes. If you take
neurons in culture and you add mercury to it, you generate
neurofibrillary tangles, the diagnostic hallmark of the
disease. You see the level of glutathione drop dramatically,
which is also found in these type of diseases. You see the
hyper-phosphorylation of protein called Tau which is only seen
in Alzheimer's disease, and it increases the production and
secretion of beta-amyloid protein which makes the senile
plaques, which is the other major diagnostic hallmark of the
disease. So if you have all of the scientific evidence behind
it, this is where most people in medicine would look at it and
say, hey, this is kind of conclusive evidence. But it is done
on animals, it is done on a thing. So unless we take somebody
and do it on a human, the dental association does not want to
believe that this is something that is relevant. Most medicine
fits into this category.
And I would like to point out one other----
Mr. Burton. Doctor, if you could summarize.
Mr. Haley. Sure. OK. Mercury is classified by dentistry as
a Class I material, totally safe. If I order that and it comes
into my chemistry department, it is placed in the most toxic of
categories. So there is the difference; the cavalier attitude
that it is safe, it is not toxic, and the attitude that, no,
this is one of the most toxic chemicals known. I think they
need a wake-up call. Thank you.
[The prepared statement of Mr. Haley follows:]
[GRAPHIC] [TIFF OMITTED] T4699.015
[GRAPHIC] [TIFF OMITTED] T4699.016
[GRAPHIC] [TIFF OMITTED] T4699.017
[GRAPHIC] [TIFF OMITTED] T4699.018
[GRAPHIC] [TIFF OMITTED] T4699.019
Mr. Burton. Thank you.
Dr. Richardson.
Mr. Richardson. Thank you. Ladies and gentlemen of the
committee, it is an honor and privilege to address you this
morning. Dental amalgam is the single largest source of mercury
exposure in the U.S. population. This is acknowledged by the
U.S. Environmental Protection Agency, amongst other agencies in
this country. While an employee with the Canadian Federal
department of health, I was directed in 1994 to undertake an
assessment of mercury exposure and risks from dental amalgam on
behalf of that country. Subsequently in 1996, I was
commissioned by the government of Sweden to contribute an
updated assessment of those risks for their review of this
issue.
As you might expect, the work received considerable
criticism from the dental establishment, in Canada, the United
States, and internationally. Interestingly, however, my work is
not unique. At least 14 journal articles and government reports
have evaluated mercury exposure from dental amalgam, and that
is what is presented in this slide. The horizontal bars show
the different estimates of exposure ranging from the minimum to
the maximum. The green circles represent the average as
estimated by the different authors in those studies. The four
studies at the top have been authored by what I will term ``pro
amalgam'' authors who want to support the continued use of
amalgam. They are totally out of step with every other study
that has been done on mercury exposure from amalgam, including
a committee of the U.S. Public Health Service, my own study for
Health Canada, the World Health Organization, Tom Clarkson, who
is one of this country's foremost mercury researchers, and
other authors from Europe.
Therefore, the fact that mercury exposure occurs and the
likely levels of that exposure throughout the population are
not in doubt.
Other than my own work, what every other report or article
on mercury exposure from dental amalgam failed to do was ask
the question: So what? What does that exposure really mean? One
answer to that question is achieved by comparing the levels of
amalgam related exposure to what is deemed to be a ``safe'' or
reference exposure level. These are represented by the red
vertical bars in this graph. Such toxicological benchmarks are
routinely prescribed by the U.S. EPA, again amongst other
agencies. And when the mercury exposure from amalgam is
compared to what is deemed to be a safe exposure level by the
EPA, it is apparent that dental amalgam leads to excessive
exposure in a very large proportion of the United States and
Canadian population. All exposure represented by those
horizontal lines that go passed the red bar to the right are
exposures that exceed what the U.S. EPA calls a safe dose. And
in fact, if a Superfund site is contaminated with mercury, the
exposure to residents around those sites cannot exceed a dose
equivalent to that red bar. So the exposure that occurs from
dental amalgam exceeds what would be permitted at a Superfund
site.
In my own assessment of risks on behalf of Health Canada, I
concluded that a more appropriate safe or reference dose is
some 4 times lower than the reference dose established by the
EPA. Further, from the analysis prepared on behalf of Sweden,
it was apparent that the frequency of both neurological
impairments and subtle kidney effects increases with increasing
dose, but still well within the range that results from the
presence of dental amalgam fillings.
The science upon which the U.S. EPA based their safe or
reference exposure level for elemental mercury is quite dated.
The most recent article on neurotoxicity that is cited on their
IRIS data base is 1993. The keystone paper dates from 1983.
This agency has so far failed to update that reference level to
reflect and include any new science on the neurotoxicity of
mercury vapor that has been published since 1994, and there are
a lot of studies. In my submission I have listed many of them.
It is apparent from that literature that neurological effects
occur at levels of exposure much lower than believed 7 years
ago.
Mercury from amalgam crosses the placenta and contaminates
the unborn fetus, in proportion to the number of amalgam
fillings in pregnant women's teeth. Yet, no research has
attempted to identify a safe dose, if one exists, for elemental
mercury in an unborn child. Mercury from amalgam contaminates
breast milk, in proportion again to the number of amalgam
fillings in nursing women's teeth, and amalgam fillings may be
placed into the teeth of children as young as 3 years old.
Young children are a population group whose central nervous
system is still developing and in whom neurological toxins such
as mercury are more harmful than in adults. Again, however, we
do not know what effects this exposure might be causing.
Several countries, including Canada, Sweden, Norway,
Germany, and Austria, have now taken or initiated steps to
reduce or eliminate the use of amalgam as a dental restorative
material. Canada has identified an obligation of informed
patient consent and has made a series of recommendations
regarding in whom amalgam should not be used. Identified groups
include pregnant women, children, and persons with kidney
diseases, among others. In Sweden, with a national socialized
dental health care program, the placement of amalgam fillings
is no longer funded.
The Superfund program in the United States does not permit
as much mercury exposure to residents living near those sites,
as I have said previously. Yet the place of dental amalgam into
the human body is still permitted, if not promoted, despite the
fact that those exposures exceed what a Superfund site would be
permitted to occur from what is classified as a hazardous
waste.
In both the United States and Canada, efforts are now
underway to force major industries, particularly coal-fired
electrical generators, to spend hundred of millions or perhaps
billions of dollars to reduce or eliminate mercury emissions.
The reduction in mercury emissions to the environment is a
worthwhile cause worthy of your support. However, the
reductions in mercury emissions that will result from those
massive expenditures will do nothing to reduce mercury exposure
in the population, not as long as dental amalgam, the primary
source, is still in use. Industrial emission reductions will
reduce slightly mercury levels in the atmosphere and, with
time, the environment in general, but exposures in the general
population will change only marginally, if at all, since their
main source of exposure is planted directly in their teeth.
If the desired goal is to reduce mercury exposure in the
U.S. population, then massive action on minor contributors to
that exposure will be totally ineffective. Dental amalgam use
must be reduced or eliminated if a significant reduction in
mercury exposure in the U.S. population is to take place. Thank
you very much.
[The prepared statement of Mr. Richardson follows:]
[GRAPHIC] [TIFF OMITTED] T4699.020
[GRAPHIC] [TIFF OMITTED] T4699.021
[GRAPHIC] [TIFF OMITTED] T4699.022
[GRAPHIC] [TIFF OMITTED] T4699.023
[GRAPHIC] [TIFF OMITTED] T4699.024
[GRAPHIC] [TIFF OMITTED] T4699.025
[GRAPHIC] [TIFF OMITTED] T4699.026
[GRAPHIC] [TIFF OMITTED] T4699.027
Mr. Burton. Thank you, Dr. Richardson.
Dr. Fischer, how are you?
Mr. Fischer. Great. How are you?
Mr. Burton. You are recognized.
Mr. Fischer. Good morning, Mr. Chairman, members of the
committee, and guests. My name is Rich Fischer. I am a dentist.
I have been practicing for 30 years. Over 20 years ago, based
on information available at that time, I made an ethical
decision to stop using mercury in my practice. Dental amalgam,
or silver mercury fillings, whatever you would like to call
them, contribute more mercury to the body burden in humans than
all other sources, including dietary and vaccines put together.
These fillings contain 50 percent mercury, which is more
neurotoxic than lead, cadmium, or even arsenic.
To put this in perspective, the amount of mercury contained
in one average size filling exceeds the U.S. EPA standard for
human exposure for over 100 years. Put in other terms, it takes
only one-half gram of mercury, the amount in one filling, to
contaminate all fish in a 10-acre lake.
Mercury vapor escapes from dental amalgam fillings and is
readily absorbed into the body. It accumulates in all body
tissues and has been shown to cause pathophysiology, which
means abnormal changes in the way our organs function.
Furthermore, in the case of pregnant women with mercury
fillings, the mercury readily passes from her bloodstream
through the placental barrier and accumulates in the developing
fetus. Mercury from dental amalgam has also been shown to
concentrate in mother's milk, providing not only a prenatal,
but a perinatal and a postnatal exposure for the developing
child whose immune system and central nervous system are
exquisitely vulnerable to this poison.
Scrap amalgam mercury, that unused portion of the filling
material remaining after the filling is made, must by law be
handled as a toxic waste disposal hazard. It cannot be thrown
in the trash, buried in the ground, or incinerated. Yet, some
will justify storing this same mixture in people's mouths just
inches from the brain stem and declare it harmless. That just
does not make sense to me.
Governments of six other countries, including Canada,
Germany, and the United Kingdom, have placed restrictions and/
or issued advisories against the use of mercury in dental
fillings, particularly in children and pregnant women.
In addition to the direct exposure to humans from dental
fillings, there exists a secondary route of exposure from
dental offices. Published research shows that between 14
percent and 75 percent of the mercury found in municipal waste
waters originate from dental offices. This poison finds its way
into our rivers and oceans where it contaminates fish as well
as the environment.
There is not scientific debate over the following facts
regarding mercury from dental fillings:
One, mercury is more toxic than lead, cadmium, or even
arsenic.
Two, mercury escapes from dental amalgam fillings
continuously as a vapor.
Three, some 74 to 100 percent of inhaled mercury vapor is
absorbed into the human body.
Four, inhaled mercury vapor from dental fillings
accumulates in the body to levels which cause pathophysiology.
I would like to direct your attention to the graph, please.
The graph represents data on mercury intake for the unborn
fetus and newborn. On the left here, this is the fetus, this is
the first 9 months of life for the newborn, and this is the
second 9 months. I have broken this data down into those three
equal time periods.
Again, these data are taken directly from published studies
by mercury toxicologists, not from dentists publishing in
dental journals, in the World Health Organization. The intake
data again is divided into three intervals of 9 months each.
The red indicates mercury intake into the fetus and the child
from dietary sources. The black represents intake into the
fetus from the mother's fillings. The blue represents mercury
intake to the child from vaccines. And the green represents the
EPA upper limit of exposure for adults. We have no standard for
children or fetuses.
Any toxicologist will tell you that the larger and the
earlier the absorbed dose of a poison the greater the degree of
damage. The FDA has very wisely been looking at this tuna fish,
swordfish, shark situation and advising pregnant women not to
be eating those fish because of the dietary intake. I submit
that the big one has gotten away. They have not dealt with the
issue of mercury from amalgam, which is the earliest and the
largest insult to the child.
Also in my testimony there is a list of bibliography which
show that there are a number of human and animal studies
published in peer reviewed journals demonstrating the transfer
of mercury from amalgam fillings of pregnant females into the
brains of unborn babies. There are no studies that contradict
those findings.
You have heard a lot of science already this morning. I
would tell you that this issue is really not that complicated.
The Environmental Protection Agency says that amalgam is a
toxic waste disposal hazard before we put it into the mouth, it
is a toxic waste disposal hazard after we take it out of the
mouth, and it does not take a genius to figure out what it is
in the mouth. Thank you.
[The prepared statement of Mr. Fischer follows:]
[GRAPHIC] [TIFF OMITTED] T4699.028
[GRAPHIC] [TIFF OMITTED] T4699.029
[GRAPHIC] [TIFF OMITTED] T4699.030
[GRAPHIC] [TIFF OMITTED] T4699.031
[GRAPHIC] [TIFF OMITTED] T4699.032
[GRAPHIC] [TIFF OMITTED] T4699.033
[GRAPHIC] [TIFF OMITTED] T4699.034
Mr. Burton. Thank you, Dr. Fischer.
Dr. Mackert.
Dr. Mackert. Mr. Chairman and members of the committee, my
name is Rod Mackert. I am a dentist, I hold a Ph.D. in material
science, and I am a professor of dental materials at the
Medical College of Georgia School of Dentistry, and a member of
the ADA Council on Scientific Affairs. I speak on behalf of the
more than 140,000 members of the ADA, the voice of more than 70
percent of the Nation's dentists. I am grateful for this
opportunity to discuss dental amalgam, which increasingly is a
subject of controversy, the discussion often marked by half-
truths and misinformation.
I want to begin by stating categorically that dental
amalgam is a safe and effective treatment option for dental
decay. I also want to clarify the ADA's role. It is not our
intention to advocate one restorative material over another. We
are here to attest to the safety of dental amalgam. Our purpose
is also to help dentists and patients understand all of the
appropriate treatment options that are available to fill
cavities, to provide that scientific basis for professional
choice of safe materials, and to defend the rights of dentists
and their patients to make informed choices among those safe
options. And the vast majority of American dentists support us
in that purpose.
The ADA wants dentists and patients to understand dental
treatment. I call your attention to the chart on restorative
materials that is in the materials that we have provided, which
the ADA prepared to help dentists understand the various
restorative options. Amalgam is, by far, the most thoroughly
researched and tested restorative material among all those that
we dentists use. That is why we oppose any legislative or
regulatory action to limit its continued appropriate use.
One of the principal difficulties in designing a study on
low-dose neurological effects of any substance is identifying
an appropriate control group. To be valid, such studies must
compare apples to apples. In this light, a particularly
important study population is that of the Swedish Adoption
Twins Study of Aging, or SATSA, conducted by the Karolinska
Institute which awards the Nobel Prize, which evaluated twins
reared apart and control twins reared together. A total of 587
subjects with mean age of 66 years were studied. The authors
concluded, ``This study does not indicate any negative effects
from dental amalgam on physical or mental health or memory
functions in the general population over 50 years of age.''
A 1998 multi-center study by Amelcart and colleagues
examined 4,787 patients to determine whether there is a
difference in symptoms between patients with and without
amalgam fillings. They concluded, ``Based on the present
results, the first question of the study, whether patients with
amalgam fillings differ from patients without amalgam fillings
in regard to clinical symptoms, has to be answered with a clear
no. Additionally, there was no quantitatively assessable
relationship between the presence or intensity of special
symptoms and the number of amalgam surfaces.''
Many other human studies have investigated the possible
relationship between dental amalgam and Alzheimer's disease,
multiple sclerosis, adverse pregnancy outcomes, reduced immune
competence, impaired kidney function, or other adverse health
effects and they have found none. This is not to say that we
consider the book closed. Significant research about dental
amalgam is ongoing, most notably two major studies supported by
the National Institute of Dental and Craniofacial Research
which you will hear about from the next panel. We
enthusiastically support these efforts and any other legitimate
research that deepens our understanding of the science behind
dental practice.
Simply put, mercury and dental amalgam are very different
substances and using the terms interchangeably is misleading.
When mercury is mixed with other metals such as silver, copper,
and tin it forms inter-metallic compounds that behave
completely differently from liquid mercury. The ADA is not
alone in its position that dental amalgam is safe and
effective. The National Institutes of Health, the U.S. Public
Health Service, the Centers for Disease Control and Prevention,
the Food and Drug Administration, and the World Health
Organization, among others, have independently reached the same
conclusion.
The Alzheimer's Association, the National Multiple
Sclerosis Society, and the American Academy of Pediatrics all
have explicitly stated that there is no scientific evidence
linking dental amalgam with any known disease or syndrome that
these groups track. These organizations exist to understand
these diseases and to advocate for those who suffer with them.
They would not put their reputations and the safety of their
members on the line if they did not agree with the majority of
the scientific community that dental amalgam is safe.
Dentists use amalgam because it is durable and easy to
handle, and therefore particularly useful for large fillings in
back teeth on which the bite pressure is greatest. It is
especially valuable for treating children and some disabled
patients who have difficulty keeping still because it can be
placed quickly and does not require a perfectly dry
environment. Any dentist who has placed a good filling in a
moving 3 year-old can tell you how important this is.
It should go without saying that if we doubted the safety
of amalgam, its qualities, durability, ease of use, and cost-
effectiveness would not matter. But this is not the case.
Dental amalgam is safe. We are greatly concerned that
emotionally and scientifically invalid reports about amalgam
are confusing and even alarming people to the point where they
will not seek necessary dental care. Postponing needed care
only ensures that the problem will get worse. Mr. Chairman,
amalgam fillings are no threat to patients. The real danger is
untreated dental disease. Amalgam is an excellent material,
albeit only one of many, in our fight against dental disease.
We urge you to consider only valid, scientific information and
take no action that would rob us and our patients of this
valuable safe and effective therapy.
[The prepared statement of Mr. Mackert follows:]
[GRAPHIC] [TIFF OMITTED] T4699.035
[GRAPHIC] [TIFF OMITTED] T4699.036
[GRAPHIC] [TIFF OMITTED] T4699.037
[GRAPHIC] [TIFF OMITTED] T4699.038
[GRAPHIC] [TIFF OMITTED] T4699.039
[GRAPHIC] [TIFF OMITTED] T4699.040
[GRAPHIC] [TIFF OMITTED] T4699.041
[GRAPHIC] [TIFF OMITTED] T4699.042
[GRAPHIC] [TIFF OMITTED] T4699.043
[GRAPHIC] [TIFF OMITTED] T4699.044
[GRAPHIC] [TIFF OMITTED] T4699.045
[GRAPHIC] [TIFF OMITTED] T4699.046
[GRAPHIC] [TIFF OMITTED] T4699.047
[GRAPHIC] [TIFF OMITTED] T4699.048
[GRAPHIC] [TIFF OMITTED] T4699.049
[GRAPHIC] [TIFF OMITTED] T4699.050
[GRAPHIC] [TIFF OMITTED] T4699.051
[GRAPHIC] [TIFF OMITTED] T4699.052
[GRAPHIC] [TIFF OMITTED] T4699.053
[GRAPHIC] [TIFF OMITTED] T4699.054
[GRAPHIC] [TIFF OMITTED] T4699.055
[GRAPHIC] [TIFF OMITTED] T4699.056
[GRAPHIC] [TIFF OMITTED] T4699.057
[GRAPHIC] [TIFF OMITTED] T4699.058
[GRAPHIC] [TIFF OMITTED] T4699.059
Mr. Burton. Thank you, Doctor.
Mr. Stoute.
Mr. Stoute. Mr. Chairman and members of the committee,
thank you on behalf of the National Dental Association for this
opportunity to participate in today's hearings. My name is
Gregory Allen Stoute, and I am currently serving as president
of the National Dental Association. In addition, I am the Chief
of Dental Health Services for Harvard University in Cambridge,
Massachusetts, I hold a Master's of Public Health degree, and
also serve as a dental public health resident at Boston
University Goldman School of Dental Medicine, and serve as a
Lieutenant Colonel in the Medical Corps of the U.S. Army
Reserves. I have practiced dentistry for 26 years.
The NDA represents more than 7,000 African-American
dentists, both in the United States and abroad. Since 1913 the
association has been dedicated to improving the health of the
underserved and promoting safety, prevention, quality, and
equity in oral health as well as general health. We are deeply
committed to educating the consumer and helping the public make
informed choices based on sound science.
Dental amalgam has been used as a restorative material in
dentistry for over 150 years. In fact, the Food and Drug
Administration stated that there is ``more significant human
experience with dental amalgam than any other restorative
material.'' The National Institutes of Health, the Centers for
Disease Control and Prevention, the U.S. Public Health Service,
and the World Health Organization have all said that dental
amalgam is a safe restorative material.
I will simply state for the record that the NDA supports
the conclusions of these organizations that we trust and
believe amalgam is a safe and effective restorative material.
This belief underlies our position. Dentistry is a profession
built on sound science and the NDA and our members are proud to
be a part of that tradition. Because we are firm in that
belief, we will continue to advocate vigorously for its
continued availability as a treatment option.
All dental patients deserve the right to choose the most
appropriate course of treatment. Eliminating dental amalgam as
a restorative option precludes a dentist from offering his or
her patients what may be the best choice from a clinical
perspective. Dental amalgams are generally the preferred
material for large fillings in back teeth or in very deep
fillings or fillings under the gum line. Alternatives are often
less effective and clinically contra indicated in these
situations. The NDA believes that all dental patients should be
provided with a full range of appropriate treatment options.
Decisions on the most appropriate course of oral health
treatment are best made by the dentist, in consultation with
the patient, prior to treatment.
Dental caries, or tooth decay, are the most common chronic
childhood disease, five times more common than asthma and seven
times more common than hay fever. Epidemiological evidence
demonstrates that dental disease rates and dental needs are
highest in low-income and special needs populations--those who
qualify for Medicaid and the State Children's Health Insurance
Program [CHIP].
Access to quality dental care for all children, but
especially poor children, is a vital element of overall health
care and development. Unfortunately, children eligible for
Medicaid and CHIP are three to five times more likely to have
untreated tooth decay and those programs provide the only
access to oral health care for a large proportion of the
economically disadvantaged. Very often these children have
well-advanced dental disease. About 20 million children are now
covered under the Early and Periodic Screening, Diagnosis and
Treatment program in Medicaid. Nevertheless, only 20 percent to
30 percent of Medicaid-eligible children see a dentist annually
and an unknown but much smaller percentage receives
comprehensive care. CHIP extends dental benefits to millions
more children, but the law provides no mandate for dental
services.
The NDA is concerned that the movement to eliminate amalgam
will create unwarranted public anxiety, increase disparities,
eliminate access, and eliminate viable treatment options. We
believe strongly that all Americans are entitled to quality
dental care and we believe that these populations who have
always received the least care deserve to have all the dental
care options available to them. We feel that eliminating these
options will place Americans who are already disenfranchised at
an ever greater disadvantage.
The NDA believes that all publicly and privately funded
dental plans should be required to provide reimbursement for
all appropriate restorative materials. Many public and private
sector dental plans pay only for the most cost efficient
restorative material. The NDA believes that the patients and
their doctors should have the option to discuss and select the
most appropriate course of treatment. These discussions would
include the type of materials to be used and the services to be
rendered, as well as other considerations such as cost,
durability, and aesthetics.
The NDA, along with the National Medical Association,
opposes eliminating dental amalgam as an option for dental
patients because we believe this would decrease access and
increase disparities.
By the way, I have spoken directly with Kweisi Mfume, the
president and CEO of the NAACP, and he states that, ``following
delegate vote at our annual convention, our association does
not formally adopt any resolution unless it is approved by the
national board of directors, which has not met as of yet.''
Also from their health division and the health committee,
it states that they both felt that this resolution was
premature because ``the science is still not available yet to
confirm the need to support the Watson-Burton bill to phaseout
all mercury in dentistry within the next 5 years.'' And
likewise, getting the State legislators to develop similar
legislation is too soon for that as well. Thank you very much.
[The prepared statement of Mr. Stoute follows:]
[GRAPHIC] [TIFF OMITTED] T4699.060
[GRAPHIC] [TIFF OMITTED] T4699.061
[GRAPHIC] [TIFF OMITTED] T4699.062
Mr. Burton. Thank you. And I am sorry that I introduced you
as Mr. Stoute. I understand that you are Dr. Stoute as well. So
thank you.
Mr. Bender.
Mr. Bender. Thank you, Mr. Chairman, members of the
committee. My name is Michael Bender and I am the director of
the Mercury Policy Project, an advocacy organization focused on
reducing exposure in emissions from mercury. While there has
been considerable debate about the health effects of mercury
fillings, little attention has been focused thus far nationally
on dental mercury releases to the environment and their
subsequent impacts. Yet there is ample evidence from multiple
government agencies that U.S. dental mercury uses and releases
is an environmental concern that in turn presents health risks.
Due to human activities over the last century, mercury
levels have increased in the environment three-to fivefold and
are responsible for between 50 to 70 percent of the total
mercury loadings. The most recent data from the Centers for
Disease Control indicate that 8 percent of women of
reproductive age in the United States have blood mercury levels
that pose a risk to the developing fetus.
In June 2002, the Mercury Policy Project co-released a
report highlighting the pathways by which dental mercury is
released to the environment. Our study found that U.S. dentists
are among the top mercury users, on average consuming well over
30 tons of mercury per year, and are the single largest
polluter of mercury to the Nation's wastewater. And while most
human activities for mercury, and their releases, have declined
by 80 percent or more since the 1980's, this has not been the
case with the U.S. dental sector.
Approximately 70 to 100 million amalgams are placed in
Americans each year by dentists, and 70 percent of these are
replacement fillings. Extracted amalgam materials are either
rinsed down the drain, usually to a municipal wastewater
treatment system where the heavy metal builds up in the sewage
sludge, or deposited in biomedical containers that are
incinerated or placed in trash disposed in landfills or
incinerators. When amalgam waste or mercury-laden sludge is
incinerated, the mercury is instantaneously released to the
air, contributing to both the regional and global mercury
pollution. There is no debate on this point.
Studies by EPA and numerous municipalities document that
most wastewater treatment plans have high levels of mercury
with significant contributions from dental clinics. Moreover,
conditions within some dental unit holding tanks are perhaps
favorable for promoting methylation of mercury. Recently the
Association of Metropolitan Sewerage Agencies evaluated seven
major municipal wastewater treatment plants to determine and
quantify sources of mercury coming into facilities. At all
plants dental uses were identified as ``by far'' the greatest
contributors to the mercury load, accounting on average for 40
percent of the load, more than three times the next largest
source. Yet wastewater treatment plants are not designed to
reduce mercury loadings to the environment. Consequently, all
mercury either settles in the sewage sludge or passes through
the system to be discharged directly into a waterway.
However, there are cost-effective solutions readily
available today to significantly reduce dental mercury releases
through employment of best management practices and
installation and, I emphasize, proper maintenance of amalgam
separators at dental clinics. Several States, including Vermont
and New Hampshire, are currently working with their State
dental associations to foster this approach. Furthermore, the
American Dental Association has demonstrated a proactive
approach through review of twelve amalgam separators currently
available in the United States today, finding that all exceeded
testing standards and that several of the units tested
exhibited removal efficiencies in excess of 99 percent.
Our June 2002 report describes successes throughout the
United States and in many countries who have worked
cooperatively with their dental sector in promoting
installation of amalgam separators. A case in point is Canada
which has recently developed nationwide standards to reduce
dental mercury pollution. In response, the city of Toronto,
Canada, has substantially reduced dental mercury releases over
the last year solely through the installation of amalgam
separators and employment of best management practices by 1,000
of Toronto's dental practices. Data from Toronto indicate that
the total average monthly mass of mercury in the sludge has
been reduced on average by 50 to 60 percent, and that is just
over the last several months.
In a second example, a 2001 study conducted cooperatively
between the Minnesota Dental Association and the Metropolitan
Council Environmental Services quantified sludge mercury
reductions at two wastewater treatment plants before and after
amalgam separators were installed in dental clinics. The study
found significant reductions of mercury loadings from dental
clinics of between 29 to 44 percent at the two wastewater
treatment plants.
In sum, employment of best management practices and
installation of amalgam separators would divert significant
quantities of mercury from ending up in the sludge at U.S.
wastewater treatment plants and reduce disposal into landfills
and incinerators and reduce environmental releases and the
subsequent risk to humans from this dangerous toxin.
Unfortunately, at this time less than 1 percent of dentists
nationwide have installed amalgam separators. Based on
conservative estimates, the costs for U.S. dental clinics to
achieve these results would average approximately $600 per
year. What we are talking about is perhaps one to five visits
from dental patients would cover the cost for the entire year.
This is clearly a cost-effective solution to a serious
environmental problem. Thank you, Mr. Chair.
[The prepared statement of Mr. Bender follows:]
[GRAPHIC] [TIFF OMITTED] T4699.063
[GRAPHIC] [TIFF OMITTED] T4699.064
[GRAPHIC] [TIFF OMITTED] T4699.065
Mr. Burton. Thank you very much.
Let me start the questioning by asking a question of Dr.
Mackert. I think you indicated that, and I cannot remember
exactly what you said, but you indicated there is no risk with
amalgams in the mouth. Why is it, as Dr. Fischer said, it is a
toxic substance before you put it in the mouth and it is a
toxic substance after you take it out of the mouth, but it is
not a toxic substance while it is in your mouth?
Dr. Mackert. Well when amalgam is first mixed, for several
minutes after that it contains liquid mercury. The mercury
reacts with the silver and tin and other elements in the metal
powder and forms inter-metallic compounds which have completely
different properties than liquid mercury. So immediately before
it does contain liquid mercury and that is why it would be a
hazard at that point.
Mr. Burton. And it is soft when you are putting it into the
mouth?
Dr. Mackert. That is correct.
Mr. Burton. It still does have liquid mercury in it.
Dr. Mackert. That is correct.
Mr. Burton. So when you are putting it in the mouth it is
toxic?
Dr. Mackert. Well, it releases some mercury vapor.
Mr. Burton. So when you are putting it in the tooth there
is a release of mercury vapor that the patient would be subject
to?
Dr. Mackert. A small amount of vapor. And this has been
studied, how much is released when it is placed, and the amount
is small.
Mr. Burton. You are saying when it gets hard in the mouth
it is safe?
Dr. Mackert. Yes.
Mr. Burton. OK. Now after the dentist takes it out of the
mouth it is still hard.
Dr. Mackert. Correct.
Mr. Burton. So why is it toxic now?
Dr. Mackert. It is not toxic at that point.
Mr. Burton. Well we just heard from Mr. Bender here that
one of the largest contributing factors in the toxicity of
wastewater treatment plants is the mercury, and that is
something that has been said all over the world. So if it is
not toxic when you take it out of the mouth, why is it toxic
when it gets into the wastewater treatment plant?
Dr. Mackert. Well it is not toxic when it gets to the
wastewater treatment plant. The way that these are analyzed is
to digest such materials in nitric acid and you dissolve the
mercury in nitric acid or other harsh chemicals and measure the
amount of mercury and you just have a number there on your
analysis that is mercury. That does not mean that the mercury
that is in amalgam is available to be absorbed into the water
or dissolved into the water.
Mr. Burton. I think we have a difference of opinion. So let
me ask you another question. If you have mercury in your teeth,
does it wear down over time?
Dr. Mackert. Yes, it does.
Mr. Burton. So when it wears down as you are chewing, where
does it go?
Dr. Mackert. The particles of amalgam are swallowed usually
and the absorption even of liquid mercury in the gut is very
small, people have estimated 0.01 percent as the amount of
mercury that is absorbed if you swallow liquid mercury in your
gut.
Mr. Burton. But the point is it does flake off over time
and it does go into your system, this mercury.
Dr. Mackert. Well, not through swallowing. The amount of
swallowing--we have estimated this, Dr. Anders Berglund of the
University of Umea--the dissolution in swallowing is about 1
microgram per day, and this is in comparison to 5 to 6
micrograms per day that we absorb from our food and other
sources, not amalgam. So it is a small contribution.
Mr. Burton. What about the mercury vapors?
Dr. Mackert. Mercury vapor is emitted, and this has been
known since about 1979. Prior to 1979, the instruments that
were available for measuring could not detect mercury vapor
coming off of amalgam fillings after they had set.
Mr. Burton. What does the vapor do when it goes into the
mouth?
Dr. Mackert. The amount of mercury vapor that escapes from
the fillings when a person is breathing in through the mouth is
absorbed and contributes to the total daily dose. From several
different ways of examining how much that is, it is between 1
and 3 micrograms per day. I know Dr. Richardson showed a chart
of all these, but I have a paper from Dr. Clarkson, who he
mentioned as being acknowledged by both sides of this issue as
an international expert on mercury, and I just want to point
out what he said in a paper he published this year, entitled
``The Three Modern Faces of Mercury.'' He pointed out the
amount of mercury that is released, he said, ``As discussed
below, these are far below''--talking about the amount that is
released from fillings--``these are far below toxic levels.''
So here is the world's expert on mercury.
Mr. Burton. OK. Let me ask you this question. I have been
told, and I am not a scientist, but I have been told that
mercury in the brain has a cumulative effect, it builds up. In
other words, if you get a little bit in, it is hard for you to
chelate it out of your brain because of the fatty tissue in the
brain. So even though the amount of mercury vapor you are
talking about might be very low, if you ingest that, even part
of it over a period of time, would it not have a cumulative
effective which could have a dilatory effect on the brain?
Dr. Mackert. Scientists have measured about how much
mercury that is inhaled is partitioned, what we called
partitioned in the brain, and that is about 7 percent of the
total that is inhaled. That mercury has a half-time, which
means over half of it will decrease, it will decrease to half
its amount in about 21 days. This has been measured by Dr.
Clarkson's laboratory and others. So all the mercury that is
absorbed is not retained. It is fairly rapidly excreted
actually, I mean 21 days. There is another compartment that
indicates a very small amount, which it is difficult to pin
down exactly how much, but a small amount does accumulate. Dr.
Clarkson and others have pointed out that this is because it
forms compounds with the element selenium which he and others
believe that this is a biologically inactive form, it is very
insoluble----
Mr. Burton. Well that is what he believes.
Dr. Mackert. Well he's the expert in the world on mercury.
Mr. Burton. We have got a bunch of experts here.
Dr. Mackert. Not of the calibre of Dr. Clarkson. In the
area of mercury, I do not think any of these people here would
claim to be on a calibre of Dr. Clarkson. We can ask them if
they think they are and they know more about mercury toxicity
than Dr. Clarkson does.
Mr. Burton. Well, we'll hear from them. I will let my
colleague here ask a bunch of questions in just a moment.
Dr. Stoute, one of the things that you said was that
dentists should provide a full range of options.
Mr. Stoute. Correct.
Mr. Burton. Why would it be wrong for all patients to know
that there is some concern and a divergence of opinion about
amalgams? In other words, if I go into your office and you are
going to put a filling in my mouth, what would be wrong with
you telling me that there is a divergence of opinion about
whether or not the mercury in an amalgam is a problem and say
that I think it is safe, but there is this divergence of
opinion and there are other alternatives you can use, like a
composite, and it is going to cost more, but I think you ought
to know that. What would be wrong with that?
Mr. Stoute. I do not see anything wrong with that.
Mr. Burton. Do you do that in your practice?
Mr. Stoute. Yes, we do. We offer options based on----
Mr. Burton. Do you tell them about the divergence of
opinion and whether or not mercury does cause a problem in the
mouth?
Mr. Stoute. In most aspects, I would say in all aspects of
dentistry we do that. Some people have concern about x-rays and
we inform them about x-rays.
Mr. Burton. So you do that?
Mr. Stoute. Yes.
Mr. Burton. Well I would say that would be great if all
dentists did it so we would all know those things.
I saw you shaking your head and I am going to let you
respond to some of the things he said, and then I am going to
let Dr. Norwood ask some questions.
Mr. Richardson. In regards to what happens to mercury when
it is absorbed into the body, the half-life in the blood is
approximately 45 to 60 days, not 21 days. The half-life in the
brain is on the order of 30 years, not 21 days. It accumulates
there. There have been studies done on cadavers and, in fact,
the concentration of the mercury in the brain correlates with
the number of amalgam fillings in the teeth of those cadavers,
as it does in numerous other tissues of the body. And, yes, it
does accumulate in the brain, it does get locked in. Once it
crosses the blood-brain barrier it is converted to a different
form by binding with sulfhydryl groups, not with selenium, and
once in that form it cannot cross back across that blood-brain
barrier and be taken out of the brain. So that is why there is
the prolonged 25 to 30 year half-life for concentrations in the
brain.
Mr. Burton. Anybody else have any other comments real
quickly before we go to Dr. Norwood?
Mr. Haley. Yes. I have the highest respect for Dr.
Clarkson, but I would say that if you read Dr. Clarkson's
papers, he totally ignores synergistic toxicities. What we
presented here today is you cannot tell what level of mercury
is toxic unless you know a lot of things about the person, the
concentration of lead they are exposed to, cadmium, and certain
other things. The potentiation of toxicity is dramatic, and I
do not think Dr. Clarkson would disagree with me that what we
have shown with the effect of mercury on the neurons is a very
significant find and that it really lowers the level of mercury
that would be considered safe for young infants to be exposed
to.
Mr. Burton. OK. Dr. Fischer.
Mr. Fischer. Thank you, Mr. Chairman. I would have one
question to my colleague. When he says that the amount of
mercury vapor coming off the fillings is very small, I would
like to know what units ``very small'' would be, if we can get
an idea of units, and at what level would it be of concern.
Mr. Burton. OK. Dr. Mackert.
Dr. Mackert. There have been a number of different
assessments of the amount of mercury vapor that comes off of
fillings. I believe looking at all the available literature,
and I am familiar with all of the studies that Dr. Richardson
showed on his slide, but in evaluating these, 1 to 3 micrograms
a day for a person with an average number of fillings is the
amount that would be absorbed. And this compares with 5 to 6
micrograms per day that people would absorb from other sources,
including seafood.
In terms of what would be a level of concern, the World
Health Organization published numbers along that line for
people, the most sensitive group in the population where the
first sub-clinical effects would appear, and it would take
between 400 and 500 fillings, surfaces of fillings to achieve
these levels with the release rates that we know.
Mr. Burton. Dr. Norwood, I know you have some questions. I
will let you take it now.
Dr. Mackert. May I also comment on Dr. Richardson's
response. Are you saying that the half-time of mercury is 30
years, the amount of mercury a person takes in, half of that
takes 30 years for that to go away? Are you claiming that on
the record?
Mr. Richardson. I will submit to this panel a paper that
documents the half-life of mercury in the brain as being on the
order of 25 to 30 years.
Dr. Mackert. All of the mercury that is absorbed, is that
what you are stating for the record?
Mr. Richardson. Yes.
Dr. Mackert. You are sadly mistaken.
Mr. Burton. If you have a position paper on that or some
documentation, I would like to have it from both of you so we
can look at it. OK?
Dr. Norwood.
Dr. Norwood. Thank you very much, Mr. Chairman. I have got
so many questions I do not know where to begin.
Mr. Burton. Well there are only two of us so I am going to
let you go for a while.
Dr. Norwood. Thank you, sir. I want you to know that I
recognize this is not my committee and I am going to mind my
manners. I really would not be this nice if this were a
Commerce Committee meeting. But having said that, Mr. Chairman,
I was greatly and personally offended by the remarks in the
opening statement from Congresswoman Watson and I would like
your permission to respond to that in writing for the record
rather than making a big to-do about it right here.
Mr. Burton. Sure. Without objection, that is fine, Doctor.
Dr. Norwood. Dr. Haley, you are a chemist. Yes or no?
Mr. Haley. Yes.
Dr. Norwood. Do you have degrees in biology?
Mr. Haley. I did 3 years post-doctor at Yale in physiology
and my major emphasis area in chemistry was in biochemistry.
Dr. Norwood. OK. I understand. You must be a smart guy
because that is a hard subject.
Mr. Haley. I enjoy it.
Dr. Norwood. Good. I see that you do. I noted, and I have
no idea whether your scientific work is correct or not, and
would not question it anyway at this point, but I did note that
most of it was about mercury, the toxicity of mercury.
Mr. Haley. What I talked about today, yes. Most of my work
is not about mercury.
Dr. Norwood. What is most of your work about?
Mr. Haley. About the structure and function of nucleotide
binding proteins that regulate body functions.
Dr. Norwood. Thank you. I got you. [Laughter.]
But your scientific work today was about liquid mercury.
And our hearing really is about amalgam, a metallic compound
that varies in percent but is at least 50 percent silver. So I
do not question you, I bet you are right about the toxicity of
mercury. But that is not what we are here about. We are here
about the possibility of considering banning a major
restoration material in this Nation that will affect dental
health. So we thank you for being here, mercury you may be
right on, you may be right about the environment, but we need
to talk I think about what we are here about, which is the
amalgam filling.
It is clear to me from my work in the Commerce Committee
with the EPA that there are two or three known things. No. 1,
you can buy a scientific report saying anything you want to
say. It just does not matter. Whatever the opinion is that you
want you can get it paid for and get it done. I have seen that
for 8 years in the EPA. So I do not know who is right or who is
wrong about the science. I tend to think probably Dr. Clarkson
is one of the world's foremost toxicologists in mercury. Do you
still stand by that, Dr. Mackert?
Dr. Mackert. Yes, I do.
Dr. Norwood. Do you agree with that, Dr. Haley?
Mr. Haley. Yes, I mean he works primarily on methyl-
mercury. And to say that he would understand the toxicity and
medical effects of mercury any better than any other well-
trained bio-chemist, I would not give him--it is the area he
worked in. But it is something you teach to freshman----
Dr. Norwood. That is his area of specialization, like yours
is whatever that long list was?
Mr. Haley. He mainly works with methyl-mercury. Most of the
research I have read from Dr. Clarkson's laboratory has been on
the mercury that comes from fish, not from amalgams.
Dr. Norwood. So he is an expert like all of you are
experts, for which nobody here dare define the word ``expert?''
Mr. Haley. Probably. But I would point out one thing. We
did talk about amalgams. I get the same effect if I take an
amalgam made outside the mouth or in a tooth that has been
given to me by a dentist, if I drop it in water and I take that
water after a period of time, and I showed that on the slides,
and add that to brain tissue enzymes or neurons in culture, it
is toxic. So the amalgams release mercury. And I tell you the
problem here, which I would challenge you and Dr. Mackert,
let's make 1,000 amalgams outside the mouth and send it to Cal
Tech and Harvard and the major science institutions in the
United States and let's live with how much mercury, let's
determine how much mercury comes out of amalgam with no
brushing, brushing 1 minute a day, and----
Dr. Norwood. Dr. Haley, I do not know that test has not
been run. I do not know that study has not been run. Are you
telling me you know of every study ever done with amalgams?
Mr. Haley. No.
Dr. Norwood. Of course you do not.
Mr. Haley. I am telling you that I have done it in my lab
and I get results that totally disagree with what Dr. Mackert
says.
Dr. Norwood. Dr. Mackert, do you want to respond to that?
Dr. Mackert. There is a big difference in doing a study in
a lab in a petri dish and doing human studies. Always the first
step is you look in the laboratory study, then you look in
animals, and then you look in humans. All the studies that I
referenced today were in humans. If these theoretical
possibilities Dr. Haley has raised were true in actual fact,
then we would see them in these human studies that have been
done, and we do not.
Mr. Haley. This is not theoretical. This is absolute----
Dr. Norwood. Excuse me. We need to have order. It seems to
me that it is hard to refute that only the EPA, who I have
mentioned earlier is the one who buys the studies they want, is
saying that amalgam is toxic and we cannot get the CDC or the
FDA or the Public Health Service or the World Health
Organization--I mean, come on, are these people--I am not
asking a question just making a statement. [Laughter.]
I saw you warming up. I am going to ask you a question in
just a minute. It seems to me all of these people are not in
cahoots with the ADA. I do not believe they are. And this all
says to us that we do not really know that you are right at all
about what you are saying about the toxicity. People like me
know what happens if you are wrong and you get rid of this
restoration, which in many cases nothing else we have today
will work. So I am just asking you to be just sort of real
careful with what you are saying now.
Dr. Haley, Dr. Linder asked me to ask you a question, and I
am not sure if he wanted to know this on a personal basis or
just wanted to know in general. But he wants to know if there
have been any studies that show a higher incidence of
Alzheimer's disease in retired dentists.
Mr. Haley. There have been no studies done.
Dr. Norwood. Anybody know of any?
Mr. Haley. I do not know of a one. I do not know of a
study. This is a thing that says there is no proof of amalgams
being toxic or being dangerous or causing disease. There is no
proof that it does not.
Dr. Norwood. I understand. But there is absolute proof of
the damage done to the dental health of this country if you
eliminate it. I can tell you about that. I know something about
that.
Dr. Mackert, next year I will have been a member of the
ADA, American Dental Association, for 40 years and I can
guarantee you they do not gag me on anything or I would not
have paid my dues. I would have just said good-bye and leave.
Are you aware of any gag rules in our Code of Ethics about
talking to our patients?
Dr. Mackert. No, I am not. In fact, the ADA encourages
dentists to discuss treatment options with patients. The ADA is
concerned that they not misinform patients on this or any other
issue and encourage patients to subscribe to treatments that
are not in their best interest. They would certainly be opposed
to that.
Dr. Norwood. Well I feel fairly certain that there are not
any gag rules. And if there were, we are an ornery group,
dentists are, and we would not pay them any attention anyway.
Most of us, Mr. Chairman, do talk to our patients about
what their alternatives are. Most patients do not want to sit
there and have me or any other practitioner respond to them on
the details of what is in, for example, amalgam fillings,
although none of us that I ever knew of would--you know, what
the heck, if you do not want amalgam, that is OK. I used to
make a lot of money using gold, probably the best restoration
known to man. The only reason we do not use it all the time now
is because if we did another 30 percent of Americans would not
be able to go to the dentist. That is why we do not do it. That
is the restoration of choice for us.
Part of our job is to treat Americans and we have to be
very concerned about the cost because in dentistry, unlike
medicine, thank God, we do not have the Federal Government
funding everything that we do. People pay out of their own
pockets. And we have to keep that in mind if we want them to be
treated. And that is really what we are there for is to treat
those patients. Now if you want to tell a patient they need to
have all their amalgam fillings taken out so you can put in all
new fillings, I would not lose, I would not do badly in that
arrangement to tell you, sit down, let's take them all out and
do them all over again. We are a capitalistic country; I am
going to make a little profit on every one of them I take out
and every one of them I put in. So it is not that we mind doing
that. If that is what a patient wants us to do, let's do it,
although I would question it.
Dr. Fischer, I want to ask you about that. What I know of
you is you are a really nice guy, a good guy, concerned, and
really believe this honestly. But let me ask if I could just
yes or no questions. You talk about the danger to children from
dental amalgams. Does the American Academy of Pediatrics agree
with you? Just yes or no.
Mr. Fischer. I do not know. About what?
Dr. Norwood. Whether dental amalgam is dangerous to
children.
Mr. Fischer. Did they say that? Is that what you are asking
me?
Dr. Norwood. No. You believe that, don't you?
Mr. Fischer. I believe it is dangerous to some children and
to some people, yes.
Dr. Norwood. Does the American Academy of Pediatrics agree
with you?
Mr. Fischer. As I say, I do not know what they say about
it.
Dr. Norwood. Well you ought to, it seems to me.
Mr. Fischer. I am not a pediatrician.
Dr. Norwood. No, I know, nor a physician.
Mr. Fischer. Right.
Dr. Norwood. But if you are going to tell people this
material is dangerous, it should be I think of interest what
the entire medical community that treats children think.
Next question. You talk about a relationship between dental
amalgam and autism. Yes or no, does the Autism Association
agree with your position on dental amalgam?
Mr. Fischer. First of all, I do not tell patients it is
dangerous. You asked me if that was my opinion, and it is. Do I
tell that to patients? No, I do not. So let me clarify the
first question.
Dr. Norwood. You do not tell patients that you are
concerned that they should not have dental amalgam, you just do
not give them the option?
Mr. Fischer. I do not give them the option because I do not
want to expose the patients, my staff, or myself to the
material. So that is an option we do not give. If they want it,
we refer them out for that. I do not do root canals either, we
refer them out.
Dr. Norwood. Do you basically think then that there is a
negative relationship between dental amalgam and autism,
patients with autism?
Mr. Fischer. Again, I am not a physician and I cannot make
a medical diagnosis. But from the American Academy of
Pediatricians, they say in one of the conclusions in this
report, ``Mercury in all its forms is toxic to the fetus and
children.''
Dr. Norwood. Of course, mercury. Who the hell would
disagree with that. We are not talking about mercury though. I
would have loved to have brought some mercury and put it out on
that table and then put a big wad of amalgam and ask you to
pick each of them up. Have you ever tried to pick up mercury?
Mr. Fischer. OK.
Dr. Norwood. Me too. It is not easy.
Mr. Fischer. The point being?
Dr. Norwood. The point I am making to you is there is a
difference between mercury and amalgam.
Mr. Fischer. Are you saying that there is no mercury in
amalgam?
Dr. Norwood. Did I say that?
Mr. Fischer. No, but----
Dr. Norwood. I sure didn't.
Mr. Fischer. OK.
Dr. Norwood. Now since I am going to ask the questions, let
me go to the next question. You talk about a relationship
between dental amalgam and Alzheimer's disease. Does the
Alzheimer Association agree with you on your position on dental
amalgam?
Mr. Fischer. I did not speak about Alzheimer's disease.
Dr. Norwood. Do you have a position on that?
Mr. Fischer. No, I am not a physician or a neurologist.
Dr. Norwood. Did you have a position on that, Dr.
Richardson?
Mr. Richardson. No. It was Dr. Haley who spoke on
Alzheimer's.
Dr. Norwood. Do you have a position on that?
Mr. Haley. Yes. I think absolutely you can say that
exposure to mercury would exacerbate the clinical condition we
call Alzheimer's disease since it causes all the aberrant
biochemistry and hallmarks to be produced.
Dr. Norwood. And does their association agree with you?
Mr. Haley. I have never talked to them. But they are just a
group of lay people. They are not scientific body. So there are
a lot of committees who do not know anything about this.
Dr. Norwood. How do you know they are a group of lay
people? Since you have never talked to them, I would like to
know how you know that.
Mr. Haley. I read their literature, I know when they are
out raising money, I talk to the people at conferences that
have Alzheimer's booths.
Dr. Norwood. Well have you ever mentioned to them, hey,
guys, you ought to be on my side and be against dental amalgam,
this is real bad for Alzheimer's and your association?
Mr. Haley. Yes, I have. I sent them a letter a long time
ago.
Dr. Norwood. And do they agree with you?
Mr. Haley. No, they did not fund me.
Dr. Norwood. Thank you. Multiple sclerosis, that society
does not agree either. Do you ever advise your patients, Dr.
Fischer, with multiple sclerosis and other diseases that they
ought to have all of their amalgam fillings removed?
Mr. Fischer. I am glad you asked me the question because
the answer is, no, I have never advised any patient to have
their amalgams removed. When they come to me and ask me to do
that, even if it is based on a referral from a physician, we
explain the options to them--I give them the ADA materials
without any references to safety but they say it is safe and it
is inert. We give them that material as well as some of the
scientific references and then we let them make their own
choice. If they decide to get them out, we have them sign an
informed consent form after we fully inform them. So, no, we do
not recommend that they get them out.
Dr. Norwood. They said you were a good guy. But the
question is if patients come in and they have a mouth full of
amalgam, which you are on record very clearly thinking that is
a very dangerous thing, do you advise them to remove their
fillings?
Mr. Fischer. No.
Dr. Norwood. That is an interesting concept. I will close,
Mr. Chairman, if I may, with one last question.
Dr. Mackert, it seems that if dental amalgam were banned,
frankly, the dental profession would make a lot more money
because of the cost and the time that is associated with using
other restorative materials, which, by the way, Medicaid
patients do not all get amalgams. It was implied earlier that
there was nothing else that Medicaid patients could ever get.
That is just not true. It varies State by State. But tell me
why you think the ADA is fighting so hard to keep amalgam as a
restorative material.
Dr. Mackert. In a number of situations, the ADA has
advocated positions that are not necessarily in the economic
interests of dentists, and I think fluoride is a good example.
This has been vigorously opposed by some groups but the ADA has
been steadfastly behind water fluoridation even though it
actually works against the economic interests of dentists. And
I think this is a similar situation where there is no economic
interest for the ADA or dentists or even dental manufacturers
who have told me, at least one manufacturer told me they
actually make a bigger profit on the resin composite materials
than they do on amalgam. So they do not have any vested
interest in the continued use. It is just that amalgam is one
option. For example, if patients are allergic to ingredients in
the resin composites and we ban amalgam, what are they going to
use on those people? And people are allergic to things like
hydroxy ethyl-methacrylate which is used in dental bonding
agents. It is one of the most potent allergens used in
dentistry. If we ban amalgam, then what are these people going
to use for a filling?
Dr. Norwood. Mr. Chairman, people like myself who have
spent their life trying to take care of patients in dental
health, we are very concerned about this, and you pointed out
some of it. We just do not have some alternatives in some
places. We would find alternatives or we would do something
different if we knew for a fact that this is harmful. What we
do know is, my own personal experiences dealing and living with
this and dealing with amalgam everyday, that it does not appear
to be harmful to people that I am aware of. And the other part
of it is that if we knew it to be harmful, we would find
something else. But we cannot do that with bad science. We
cannot do that with misconceptions in science that are not
always right.
Dr. Mackert, do you know who out there, for example, what
are the groups that are interested in banning dental amalgam?
Who is out there talking about this?
Dr. Mackert. Well, there are several groups. One is called
DAMS, which I believe stands for Dental Amalgam Mercury
Syndrome. Another is the IAOMT, which is International Academy
of Oral Medicine and Toxicology, which was founded by Murray
Vimy, a Canadian dentist in 1984, and almost the first action
that group took in 1984, before most of these studies were even
conducted, was to issue a press release calling for the banning
of amalgam. So almost the first thing they did as an
organization was to call for the banning of amalgam. So even
before Vimy and Lorscheider had done their studies, they were
calling for the banning of amalgam.
Dr. Norwood. Who is that holistic dental society?
Dr. Mackert. I am not sure.
Mr. Burton. Dr. Norwood, we do have one more panel and I
will give you liberty to ask as many questions as you want. I
would like to ask just a few more questions of this panel.
Dr. Norwood. You have been very kind.
Mr. Burton. You are a good man, even though we have a
little disagreement here.
Dr. Haley, what is the difference between dental mercury
and a jar of pure mercury? What is the difference as far as
toxicity is concerned between a dental amalgam with mercury and
a jar of pure mercury?
Mr. Haley. The mercury vapor coming off of liquid mercury
and the liquid vapor coming off of amalgam fillings is the same
thing. It is identical, absolutely chemically identical.
Dr. Mackert. Could I comment on that? Are you saying that
it is the same amount that comes off?
Mr. Haley. Of course not. When you form metallic bonds in
amalgam fillings and reduce the vapor pressure of the mercury
and it slows the evaporation rate. But what you have is
allergens that release mercury at a very low level for scores
of years.
Mr. Burton. That is the point I wanted to make. The mercury
vapor does come off of the amalgam?
Mr. Haley. Yes.
Mr. Burton. And it does chip away over time and you do
consume that, it goes into the body and is excreted through the
body.
Mr. Haley. Yes, 80 percent of the vapor that is inhaled in
the body is retained by the body.
Mr. Burton. You said 80 percent?
Mr. Haley. Yes.
Mr. Burton. OK. Now when it goes into the brain, I have
been told by leading scientists and doctors from all over the
world that the fatty tissue in the brain holds that in there
more than any other part of the body, so there is an
accumulation of the mercury over a period of time. Is that
correct?
Mr. Haley. The aspect is that mercury is what we call a
hydrophobic gas, it would rather be in the fat. It will
partition into fat tissue versus water. Mercury is not very
fond of water. However, when it is in the brain it gets
converted to the HG2+ and it binds to proteins.
Mr. Burton. So it sticks around for a long time.
Mr. Haley. The fact is that versus, say, the HG2+, which
does not cross the blood-brain barrier very effectively,
mercury vapor does it with a great deal of ease. Once it is
inside and it is oxidized, the HG2+, then it does not come out.
Mr. Burton. I have a couple of questions, and I do not know
the answer, but I do have two questions here real quickly. One
is, Dr. Norwood asked about an increase in the number of people
I think that have become autistic or hurt from mercury vapors
and amalgams. I do not know what the relationship is there, but
I do know that we had 15 years ago 1 in 10,000 children was
adjudged to be autistic. Today, according to the Food and Drug
Administration, it is more than 1 in 250. We have had more than
a 40fold increase. Now that could be attributed to a number of
things, but we do know that mercury was in the vaccines and
mercury was in the amalgams of the mother and that may be a
contributing factor. We just do not know.
As far as Alzheimer's is concerned, do any of you know
whether or not there has been an appreciable increase in the
amount of Alzheimer's?
Mr. Haley. Yes.
Mr. Burton. Can you give me statistical data on that?
Mr. Haley. I would feel uncomfortable doing that, I just
know it is very significant. Every time you read a paper on
Alzheimer's disease they bring up that there is something like
I think 6 million, somewhere in that range, of Americans today
that have it and that by 2040 it will be astronomically higher
than that, I cannot remember the exact number, just that it is
in the millions though.
Dr. Mackert. Mr. Chairman.
Mr. Burton. Yes?
Dr. Mackert. I was just wondering if I could comment on
that question.
Mr. Burton. Sure. Sure.
Dr. Mackert. It is interesting that the use of dental
amalgam has actually declined over that same period that you
mentioned on autism and resin composites have increased till
this year they are more than half of the restorations placed.
So, actually, if you are looking for something to track--and I
am not at all suggesting composites are behind it--but you
would actually see the correlation between composite and
Alzheimer's and autism rather than with amalgam since amalgam
use has declined.
Mr. Burton. I did not say it was just from that source.
When Dr. Norwood and I get our flu shot, there is mercury in
that flu shot. A lot of people do not realize that and I do not
think many of our colleagues know that.
Dr. Norwood. It has affected us both too, I am pretty sure.
Mr. Burton. Yes. Sure. [Laughter.]
But the point is there have been a number of things that
could be contributing factors to that and that is why I asked
that question.
Is there a peer reviewed study that shows mercury fillings
are safe? Is there any peer reviewed study that you know of
that shows they are safe?
Dr. Mackert. The difficulty in showing that any material is
safe is that you have to do several things. You have to
identify potential adverse effects, you can study, for example,
multiple sclerosis or even subtle changes in enzymes, and if
you look at those in a study, that is all you know is whether
it causes that one thing that you have studied. And there are
thousands, if not millions, of things that we could study that
we could try to correlate with the presence of amalgam
fillings. Many of those studies have been done but we have not
looked at everything. It is not possible to do so. We do not
have enough money or enough people to look at everything. But
the studies that have been done so far indicate that, as the
ones I have cited and others that are in our statement for the
record, these do not indicate any adverse effects from amalgam.
Mr. Burton. Let me ask you one more question, and any of
you can answer this, and then we will get on with the next
panel. I would like to end with a little comment. Are removed
mercury fillings a hazardous waste, Dr. Mackert?
Dr. Mackert. According to the EPA test that is done to
determine whether something is a hazardous waste, this was
studied, amalgam was subjected to this test and it does not
qualify as an EPA hazardous waste, according to my
understanding.
Mr. Burton. Well why don't we just flush it down the
drains? They do not do that anymore, do they? What does a
dentist do with an amalgam when he takes it out of a person's
mouth?
Dr. Mackert. Well, I all the time get mailers and packages
from these different recycling companies that offer me money
for amalgam scrap and other metal scrap. So many dentists, I do
not know what percentage, but many of them collect this and
turn it in to have the metals----
Mr. Burton. I am not talking about many. I am saying when
dentists are taking a filling out of a tooth, are they allowed
to just flush it down the toilet or down the drain?
Dr. Mackert. There are amalgam separators, there are traps
and stuff that collect various amounts of that mercury. This is
not an area of my expertise. There are others here I think that
might better answer that question.
Mr. Burton. Does the ADA or any of its affiliate
organizations, such as the AD Health Research Foundation, hold
any patents or reap any financial benefit from mercury or
amalgams?
Dr. Mackert. Well amalgam was invented long before the ADA
was even established as an organization. So, obviously, the ADA
was not around when amalgam was invented. As with all different
materials, the Health Foundation works on improvements of
materials, including amalgam. There were two patents issued I
believe in the 1980's which were never exploited, never
licensed.
Mr. Burton. So they do not make any money off of amalgams?
Dr. Mackert. They do not. In fact, the ADA Health
Foundation was the organization, an ADA scientists named Ray
Bowen was the man who invented the dental composite, the white
filling that is used.
Mr. Burton. OK. OK. Let me ask Mr. Bender and Dr. Haley a
question. The amalgams, after they are taken out of the mouth
and disposed of, are they considered toxic by the
environmentalist and the EPA?
Mr. Bender. I am not aware of the study that Dr. Mackert
refers to in terms of whether or not they pass or fail the
EPA's TCLP test. What I do know is from an environmental
standpoint dentists are not regulated in terms of their
disposal. That is one of the major problems. What I do also
know, I indicated in my testimony, that approximately less than
1 percent of dentists in the United States today have amalgam
separators. In fact, talk about commissioning studies to get
the answers that you are looking for, the ADA recently
commissioned with a group called Environ to basically come out
and say that amalgam separators were not a cost-effective
approach to go.
Mr. Burton. Dr. Haley, the amalgam, when they come out of
the mouth and are flushed down the toilet and down the drain
and go into the water----
Mr. Haley. They place them in sealed containers to keep the
mercury vapor, when they are sitting in the dental office, from
contaminating the air and making it unsafe for people to work.
Mr. Burton. Dentists put them in a sealed container?
Mr. Haley. In a sealed container under a liquid solution
that will bind the mercury vapor if it is released.
Mr. Burton. Is that a common practice among dentists?
Mr. Haley. I think so.
Mr. Burton. Is that right?
Dr. Mackert. That is. And the reason for that, as I
mentioned earlier, is that when the amalgam is first mixed it
does release mercury vapor for a short time until it completely
sets. So that is why it is placed under liquid, usually a
photographic fixer or other sulfur containing liquids are used.
Mr. Haley. Research has absolutely shown that amalgams
release mercury for years after they are hardened. Dr. Mackert
is just flat wrong in his assessment.
There was a study when they used a material called composel
and they showed that it released 43 micrograms per centimeter
squared per day and it did so consistently for 2 years.
Unfortunately, this was put in the mouths of Americans. And the
person who published this research in Clinic Dental Research
was from Singapore University, it was not the FDA or the ADA. I
do not think they look at it. I had a debate with the dental
department at the University of Kentucky this Tuesday and I
asked them, ``Do you have any devices in the school of
dentistry that measures mercury in the air or in the water?''
They did not have a thing.
Dentists are allowed to do things that the rest of us are
not allowed to do. If I were to do experiments on mercury, I
have to have it picked up as a toxic waste. Mercury coming into
my department is classified as in the most toxic category of
chemicals whereas the FDA dental branch classifies it as a
totally safe material, as safe as a bedpan. There is a lack of
common sense being applied here. And that is what I am saying.
Do not believe me, do not believe him, make amalgams outside of
the mouth, get a Government group to go check the amount of
mercury that comes out under abrasion, under heat, and then
settle this. This is not rocket science; this is simple stuff.
And I know I am right and I know the amount that Dr. Mackert
says comes out of amalgam fillings is wrong, because if he
talks about the amount that comes out per surface area exposed,
and if you look at the amount that is in the urine and you
multiply that by 9, because 90 percent of the mercury comes out
in the feces, you cannot even possibly account for that amount
of mercury with his values.
Dr. Mackert. Let me just comment on that study. I know
Professor Chou, he is a friend of mine, who published that
study. It is interesting, they only pick the one material that
is not even sold in the United States, never has been sold in
the United States, the composel that he mentioned, it is not a
standard formulation of amalgam at all. Even in that study that
he mentioned it says, so he could not be unaware of this, that
it released much more mercury, in fact, 400 times more mercury
into solution than any other amalgam that was studied. So why
does he pick that one amalgam?
Mr. Burton. Let me interrupt here just a second. I think
this is a very interesting debate. Would the American Dental
Association and your association, Dr. Stoute, be willing to
perform the kind of test that he is talking about? In other
words, make amalgams and put them into different kinds of
conditions, send them to major scientific research laboratories
around the country--I would be very happy to facilitate that--
and let them come up with an answer to this because the
American people would like to know. Now if the ADA says no, I
would like to know why.
Dr. Mackert. We are willing to fund any studies or----
Mr. Burton. Are you willing to do that? Are you willing to
make the amalgams----
Dr. Mackert. It has been done.
Mr. Burton. It has been done?
Dr. Mackert. Yes. The study that he mentioned talks about
other amalgams and they are 400 times lower than the one that
he happened to cite.
Mr. Burton. The amalgams used here in the United States,
the amalgams that are used in dentists offices all across the
country----
Dr. Mackert. The other amalgams that were in that study
were used in the United States.
Mr. Burton. Would the ADA be willing to do a study where
they took amalgams, 100, 200, whatever it takes, make them, put
them under different conditions, send them to the various
laboratories around the country and let the American people
know what the results are? Would they be willing to participate
in that kind of a study?
Dr. Mackert. We would. But again, these studies have been
done. The study that he cited has that very data in it that he
failed to cite.
Mr. Burton. If you would be willing to do that, that would
be--so you are speaking on behalf of the ADA that you would be
willing to do that?
Dr. Mackert. We will respond in writing to that. You know,
I am a faculty member of the Medical College of Georgia, I do
not work for the ADA. I cannot tell you what the ADA----
Mr. Burton. You are representing the ADA today.
Dr. Mackert. Yes, I am. But I do not work for the ADA.
Mr. Burton. Who would make that decision?
Dr. Mackert. The Council on Scientific Affairs, of which I
am a member, I start my term in January.
Mr. Burton. So you are a member of that. Would you
recommend that they would do that?
Dr. Mackert. Well, if we want to be cost-effective in our
expenditures of research dollars, if something has already been
done multiple times, then it is not cost-effective to do it
once again. If that information is not available in the
literature, we would certainly be very interested in pursuing
that and funding that.
Mr. Burton. I do not see why it would not be something that
you would want to do, because it would put an awful lot of this
debate to rest.
Dr. Mackert. It would never put it to rest because--I am
sorry, I keep interrupting.
Mr. Burton. I just think it is something that would allay a
lot of people's concerns and fears. Because Dr. Haley I think
has said very, very clearly that the amalgams outside the mouth
are toxic, they release toxic vapors.
Dr. Mackert. But they are not toxic. Toxic means it causes
demonstrable adverse health effects, and they do not. There are
studies that have shown that, studies that have looked at this,
thousands of subjects, all the things that I mentioned,
Alzheimer's disease, multiple sclerosis, adverse pregnancy
outcomes. You can always think of more symptoms to look for but
we have looked at the major ones people have brought up as
adverse health effects, reduced immune competence, kidney
function, all these studies have been done and looked at it and
compared groups of people with and without amalgams and they do
not find any difference.
Mr. Burton. OK. Well you are not for doing the study then?
You do not want to do it?
Dr. Mackert. If the study has already been done and we have
the data in the literature----
Mr. Burton. Has that kind of study been done, Dr. Haley?
Mr. Haley. Just one study he reported. When I bring up the
aspect of the 43 micrograms, it is that here was an amalgam
filling that was used and it was placed in the mouth of
Americans and nobody tested it.
Dr. Mackert. No, it was not.
Mr. Haley. I have tested, and I teach a class called
Mercury, Science, and Politics, and I have students measure the
amount of mercury that comes out of amalgam fillings. And while
it is not as high as the composel, which is extremely high, it
still is very significant. And when you brush it, it goes up to
43 micrograms per centimeter squared. If you abrade the amalgam
filling 30 seconds, twice a day, you get a huge increase.
Now I know high copper amalgams release more mercury than
low copper amalgams. I have read all the stuff. What we have to
do is talk about the specific material that is being put in
people's mouths and just test it. That is the only thing I
think that is needed. If you are going to use it, test it and
say how much comes out just setting quiescently in a test tube
in water, and then abrade it, just brush it, and say how does
it respond when you brush it with say a medium bristle
toothbrush, add heat to it like you are drinking coffee and see
does it increase it. You have got to do these studies. And no,
these studies have not been done.
Dr. Mackert. Yes, they have.
Mr. Haley. Where?
Dr. Mackert. Anders Berglund, at the University of Umea in
Sweden, did exactly those things. He monitored patients every
30 minutes throughout the day, including all night----
Mr. Haley. Not in a sealed container.
Dr. Mackert. Let me finish. He had them drink coffee and,
contrary to the allegations of the anti-amalgamists, it does
not cause an increase in mercury release. Many foods actually
cause amalgam release to go down.
Mr. Burton. OK. Let's end this panel. Let me just say, and
I have all kinds of literature that we have studied and read,
mercury is a toxic chemical, mineral. Nobody has any doubt that
if mercury was lying on that table there, nobody would want to
be messing with it because it is toxic. It is in amalgams. It
is in some of our vaccinations. And in many people's minds,
mine included, there is a substantial risk. I have had my
amalgams out. I am going to get even my capped teeth, the ones
that have gold over them that may have a filling in them, I am
going to get those out because I just do not want the risk,
even though you would not agree with me.
If there is any doubt whatsoever, it seems to me that
people ought to err on the side of safety. And I think the
American people need to know at least that amalgams contain 50
percent mercury. They do not know that. I did not know that and
I am a fairly well-read person. I think if the American people
were made aware, just made aware of the fact that the amalgams
contain 50 percent mercury, knowing even a small amount of what
they do about chemistry and about the biology of the human
body, I think an awful lot of them would opt for another kind
of filling.
It just seems to me--I understand that Dr. Norwood is going
to oppose this bill, it is probably not going to go anywhere--
that we need to have more hearings on this subject, and we will
have more hearings. This subject will be discussed and debated
and it will be illuminated. At the very least, the American
people will know there is mercury in fillings and they will be
able to make an informed decision on whether or not they want
to have that in their mouth, just like we have been trying to
illuminate the issue of whether or not there should be mercury
in vaccinations for children. My grandson got nine vaccinations
in 1 day. He was a wonderful boy. Two days later, 3 days later
he became autistic and he is ruined in part for life. He got 47
times the amount of mercury that is tolerable in an adult in 1
day and it made a big difference I believe in his life.
So when somebody asks me should there be mercury in
vaccines, I say hell no. And if somebody asks me if mercury
should be in anything that goes into the human body, I am going
to say I do not believe so. I am a layman, I am not a
scientist, but from what we have heard at our hearings and from
scientific research around the world, I do not believe it
should be in there. But at the very least, I think dentists
ought to inform the American people that they are half mercury,
and if the American people know that, I think they will make
the decision themselves.
With that, I think we ought to go to the next panel. Thank
you all very much. We appreciate your comments.
We will take a 5-minute break here, if you like, and I will
come right back.
[Recess.]
Mr. Burton. The committee will reconvene.
We will now hear testimony from the second witness panel. I
would appreciate those individuals coming to the table. Dr.
Lawrence A. Tabak, Director, National Institute of Dental and
Craniofacial Research, National Institutes of Health; and Dr.
David W. Feigal, Director, Center for Devices and Radiological
Health, Food and Drug Administration. I appreciate your being
so patient listening to all the discussion and debate.
Would you please rise and be sworn.
[Witnesses sworn.]
Mr. Burton. Dr. Tabak, do you have an opening statement?
Mr. Tabak. Yes, Mr. Chairman, thank you.
STATEMENTS OF LAWRENCE A. TABAK, DIRECTOR, NATIONAL INSTITUTE
OF DENTAL AND CRANIOFACIAL RESEARCH, NATIONAL INSTITUTES OF
HEALTH, BETHESDA, MD; AND DR. DAVID W. FEIGAL, DIRECTOR, CENTER
FOR DEVICES AND RADIOLOGICAL HEALTH, FOOD AND DRUG
ADMINISTRATION, ROCKVILLE, MD
Mr. Tabak. Thank you, Mr. Chairman, for inviting me here
today to discuss NIDCR-supported research on mercury in dental
amalgam, a material used to restore teeth damaged by the
effects of microbial infection or trauma.
The effects of elemental mercury exposure have been studied
primarily in occupational studies, where the exposure levels
have been on the order of 100 to 1000 micrograms per liter of
urine. Estimates of exposure from dental amalgam can range from
1.2 to approximately 20 micrograms per liter of urine,
depending on the number of tooth surfaces restored and the size
of the restorations.
In the early 1990's, the Assistant Secretary for Health
charged the PHS Committee to Coordinate Environmental Health
and Related Programs to conduct a comprehensive assessment of
the benefits and risks of dental amalgam based on peer reviewed
scientific literature. Their 1993 report concluded that
scientific evidence does not demonstrate that exposure to
mercury from dental amalgam poses a serious risk in humans.
However, the Committee's Subcommittee on Risk Assessment called
for additional research to address whether dental amalgam
creates a significant health risk to individuals. the NIDCR
responded in 1996 by launching two clinical trials designed to
assess whether exposure to mercury in dental amalgam in
children is associated with adverse neurological, renal,
immunological, microbiological, behavioral, or cognitive
effects.
These studies are comparing the possible health effects of
amalgam with composite dental fillings over time. Only children
who did not have any prior fillings have been included as
participants in order to address the concern that any possible
adverse health effects might have been caused by pre-existing
dental restorations. It is expected that both trials will be
completed in 2006.
One clinical trial is being conducted by a group of
scientists from the University of Washington in Seattle in
conjunction with a group from the University of Portugal in
Lisbon. 507 children between the ages of 8 and 10 years are
participating in this trial. Five primary endpoints are being
monitored from baseline and at 1 year intervals: three
neurobehavioral indices including combined assessments of
attention, memory, and motor domains; one neurological
assessment involving nerve conduction velocity; and an endpoint
aimed at assessing renal function. In addition, urinary levels
of mercury were assessed at baseline and are being measured at
each followup exam.
A second clinical trial is being conducted by a consortium
of scientists from the New England Research Institutes, or
NERI, in Cambridge, Massachusetts, Forsyth Dental Clinic and
Harvard University in Boston, and the University of Rochester
in Rochester, New York. 534 children between the ages of 6 and
8 years requiring at least two fillings were recruited into
this trial from sites in the Boston/Cambridge area and in
Farmington, ME. The trial is sized to detect a three-point
change in IQ over a 5-year period. Additional tests of
neuropsychological, cognitive and behavioral, and renal
functioning are also being carried out.
The conduct of both trials is overseen on an annual basis
by an independent Data and Safety Monitoring Board, the DSMB,
consisting of experts in the fields of dental restorative
materials, pediatric neurology, pediatric nephrology,
neurotoxicology, cognitive and behavioral development, heavy
metal/environmental toxicology, biostatistics and bioethics.
The DSMB has met once a year since the inception of the trials,
and meets by teleconference on an as-needed basis, to review
group distributions of endpoints and to evaluate trial
operations. Based on these data, the DSMB determines whether or
not individuals are at increased risk, whether the trials
should be ended, and whether the results should be made
available to the public.
Over the course of the trials several children have shown
higher than acceptable urinary mercury levels. When retested,
most values have been within the acceptable range. Also, some
children have shown changes in one or more of the
neuropsychological endpoints that caused concern and followup
clinical examination by the study teams. These changes,
however, have not been limited only to children receiving
amalgam and, for the most part, the problems identified seem to
have existed prior to the entry into the trial. To date, no
harmful untoward effects attributable to amalgam have been
noted in either trial, and on each occasion the DSMB has
recommended that the trials be continued.
In summary, Mr. Chairman, available scientific evidence
continues to indicate that dental amalgam is a safe restorative
material. Of course, I would be happy to respond to any
questions you might have.
[The prepared statement of Mr. Tabak follows:]
[GRAPHIC] [TIFF OMITTED] T4699.066
[GRAPHIC] [TIFF OMITTED] T4699.067
[GRAPHIC] [TIFF OMITTED] T4699.068
[GRAPHIC] [TIFF OMITTED] T4699.069
[GRAPHIC] [TIFF OMITTED] T4699.070
[GRAPHIC] [TIFF OMITTED] T4699.071
Mr. Burton. Thank you, Dr. Tabak.
Dr. Feigal.
Dr. Feigal. Mr. Chairman and members of the committee, I
appreciate your invitation and this opportunity to discuss the
issue of dental amalgam safety.
Let me begin with a brief overview of FDA's regulatory
authorities over medical devices generally and how they have
been applied to dental amalgam.
The term ``medical device'' in the statute encompasses
thousands of health products, some simple and others quite
complex. Dental amalgam, as well as its components--dental
mercury and the alloy with which the mercury is combined--are
medical devices.
The Medical Device Amendments of 1976 to the Federal Food,
Drug, and Cosmetic Act gave FDA specific authority to regulate
the safety and effectiveness of medical devices and provided a
variety of mechanisms with which to do so. These included the
classification of medical devices into risk categories, medical
device establishment registration, quality systems
manufacturing requirements, and the control of the introduction
of medical devices to the market.
Devices on the market at the time of the 1976 Amendments
were assigned to one of three classes of risk to patients.
Class I devices, posing the lowest risk, are subject to general
controls applicable to all devices. Class II devices, which
pose incrementally greater risk, are subject to additional
controls called ``special controls'' designed to address the
specific risks of the type of the product. Examples of a
special control that might be applied to a Class II device
include conformance with mandatory performance standards and,
less often, clinical studies. The riskiest devices, such as
some implants and life-supporting or life-sustaining devices,
are placed in Class III and require valid scientific evidence
of safety and effectiveness before they can be marketed. The
Act also authorizes the agency to ``reclassify'' a medical
device to a higher or lower regulatory class when warranted.
Amalgam has an extremely long history of use by oral health
care providers, well over 100 years. Amalgam consists of
roughly equal parts of mercury and amalgam alloys made from
other materials such as silver, tin, and copper. Historically,
mercury was regulated as a Class I device. Dental amalgam alloy
was regulated as a Class II because of potential risks from
variations in the chemical formulation of the alloy. The
encapsulated form of the amalgam, which consists of measured
proportions of amalgam alloy and dental mercury, were never
separately classified. However, because the encapsulated
amalgam is a combination of two classified devices, it is
regulated in the higher class of its components as a Class II
device.
In the early 1990's, the FDA became increasingly aware of
consumer concerns about the safety of the mercury component in
dental amalgam. At the direction of the Assistant Secretary for
Health, the National Institutes for Health, the Center for
Disease Control, and FDA conducted a comprehensive review of
both the health risks and clinical effectiveness of the
product.
This extensive evaluation demonstrated that the clinical
benefits of dental amalgam outweighed the observable risks,
specifically mild, transient allergic reactions among a very
small percentage of patients. In 1993, the Public Health
Service issued a comprehensive risk assessment management plan
developed with outside peer review to ensure that the NIH, CDC,
and FDA collaborated to advance the state of the science, and
to keep dental professionals current on the latest scientific
information about dental amalgam safety, and to maintain an
appropriate level of regulatory control over the product.
The PHS conducted followup reviews of the literature in
1995 and in 1997. And in 1997, FDA invited concerned groups to
submit scientific studies for review to FDA by toxicology
experts and other experts outside of FDA. Since 1997, we have
reviewed more than an additional 170 studies which, taken
together, did not change our risk profile for dental amalgam.
In addition to keeping abreast of the science here in the
United States, we and our PHS colleagues have aggressively
pursued information about the risks of dental amalgams from
public health agencies and organizations around the world. To
date, a review of the risks and benefits of dental amalgams has
not changed FDA's risk-benefit assessment.
We are planning to begin another review with NIH and CDC to
update the assessment of the scientific literature on the
health effects of dental amalgam. Once again, this later effort
will involve experts from both the Government sector and the
outside scientific community and we will solicit broadly for
information which we should review.
Let me speak a bit about the current regulatory status of
amalgam. There has been some confusion among those interested
in this issue about the regulatory status of dental amalgam and
the purpose of a rule that the agency proposed last February.
As explained earlier, mercury, alloy, and encapsulated amalgam
are all legally marketed products. Mercury is a Class I device,
amalgam alloy is a Class II device, and the combination is
regulated as a Class II.
In February 2002, FDA proposed a rule to bring all amalgam
products into Class II, requiring ingredient labeling and
perform conformance to international standards. Disclosure of
amalgam ingredients will also help dental providers to quickly
diagnose and treat rare allergic reactions to amalgam
components. Given the high level of interest in this proposed
rule, we twice reopened the comment period, and we are now in
the process of reviewing more than 750 comments submitted to
the docket.
In conclusion, Mr. Chairman, FDA is committed to monitoring
the scientific evidence closely relating to dental amalgam
safety. We will continue to exercise our regulatory
responsibilities appropriately in accordance with the best
available science. And we will continue to work with the public
health community to reduce the incidence of dental caries and
improve the quality of oral health care.
Thank you again for this opportunity. I am happy to answer
any questions you or the members of the committee may have.
[The prepared statement of Dr. Feigal follows:]
[GRAPHIC] [TIFF OMITTED] T4699.072
[GRAPHIC] [TIFF OMITTED] T4699.073
[GRAPHIC] [TIFF OMITTED] T4699.074
[GRAPHIC] [TIFF OMITTED] T4699.075
[GRAPHIC] [TIFF OMITTED] T4699.076
[GRAPHIC] [TIFF OMITTED] T4699.077
[GRAPHIC] [TIFF OMITTED] T4699.078
Mr. Burton. Thank you, Dr. Feigal.
Mr. Gilman, do you have any comments you would like to make
before we start the questions?
Mr. Gilman. Thank you for conducting this hearing. I am
sorry I had another engagement that delayed me from coming
over. I want to recognize the importance of your decision to
hold hearings on mercury levels in dental amalgams and commend
your efforts in investigating medical exposures to mercury and
other potentially toxic materials.
I think today's hearing is important because it deals with
mercury, a highly toxic element. Unlike other toxins, mercury
is unable to be filtered out or eliminated by our bodies;
instead, it accumulates over time. For that reason, efforts
have been made to reduce the level of exposure of the public to
mercury. Mercury thermometers have been phased out, and the FDA
has issued warnings that vulnerable populations such as
pregnant women and young children should avoid consuming too
much mercury-containing fish.
There is currently an ongoing debate of course within the
dentistry community about the potential for harm from the
dental amalgams which contain mercury. And while the majority
of dentists use such amalgams and see no long term harm in
doing so, a significant percentage are moving away from such
practices.
So I look forward to being able to review all of the
testimony that you are taking today, and I again commend you. I
do have some questions after the panel has finished their
testimony.
Mr. Burton. Thank you, Chairman Gilman.
You said that the FDA has been following this and checking
this out for a long, long time. Can I ask you a couple of
questions about the history of the FDA and mercury fillings,
this is from 1976 till now?
Dr. Feigal. Yes.
Mr. Burton. In 1976, Congress ordered the FDA to regulate
devices. In 1986, Proposition 65 passed in California, I am
sure you are familiar with that. In 1987, the FDA classifies
all dental fillings except encapsulated mercury amalgam. Is
that correct?
Dr. Feigal. It was not specifically encapsulated but it was
covered by the classification of its two separate components.
Mr. Burton. Well is that a correct statement, the FDA
classified all dental fillings except encapsulated mercury
amalgams? Is that a correct statement?
Dr. Feigal. That is correct.
Mr. Burton. OK. Why did they not classify that as well?
Dr. Feigal. To be honest, we do not know if it was an
oversight or if it was the intent to regulate the combination
product by regulating its two components, both of which were
classified. There is no unclassified component in the product.
But we actually have not been able to reconstruct that history.
Mr. Burton. Citizens groups sued the FDA for failing to
classify mercury amalgams in 1991 and 1993. In 1993, Public
Health Service asked the FDA to classify mercury amalgams. In
1997, OSHA backed off regulating dental offices because of FDA
promise to classify. In 1997, FDA writes a letter again
promising to classify mercury amalgams. And from 1990 to 2002,
meanwhile the FDA prohibits other mercury containing items,
including disinfectants, vaccines, even horse medicine, there
is still some in some vaccines. But did you ever classify
mercury amalgam?
Dr. Feigal. Dental mercury is classified as Class I and the
alloy has been classified as Class II, and the component is
classified as a mixture of two products, one of which is Class
I and the other is Class II, not separately classified. We have
had petitions to change the classification, but the product has
been classified for some time. I would have to get you the
exact dates.
Mr. Burton. It has been classified?
Dr. Feigal. Yes.
Mr. Burton. It said that OSHA backed off in 1997 regulating
dental offices because of FDA promise to classify. And it says
FDA writes a letter in 1997 again promising to classify mercury
amalgams. But you say it actually has not been done. You
classified the components but not the mercury amalgam itself.
Dr. Feigal. The manufacturers of the combination product
where the two are encapsulated together have been regulated
since the classification of Class I and Class II as a Class II
product.
Mr. Burton. What is a Class II product again?
Dr. Feigal. A Class II product is a product that has
specific controls. So in the case of the alloy, the amalgam
alloy, there are international standard organizations, ISO
standards and there are ANSI standards on the compositions of
alloys, recognized standards for what those compositions can
be, and they have to meet those standards.
Mr. Burton. OK. So does that mean that Class II would be
considered a toxic substance or a possible toxic substance?
Dr. Feigal. Well, the risk classification is not actually
based on the toxicity of the compound in the absolute sense. It
is based on the risk in use to the patient. And so it is not
based on environmental toxicity, on toxicity to animals, it is
based on whether or not it needs to have special controls in
order to assure that the product will be safe and effective as
used. And in this case, the control is to know what is in the
alloy.
Mr. Burton. Do you have any idea how many micrograms of
mercury vapor is emitted by a filling in the day?
Dr. Feigal. We have reviewed the same studies that were
discussed by the first panel and we have, as part of the
process over the years, gone over that literature and we
understand that literature presents a range of values.
Mr. Burton. A range from where to where?
Dr. Feigal. I would have to followup in terms of providing
that----
Mr. Burton. We have somebody here that has a mercury
amalgam. Don't you have a device that measures the micrograms
in it? Can you do that for us while we are here? I would like
for them to have that information while they are here. I do not
know how you do that.
Mr. Richardson. Someone here brought a sniffer.
Mr. Burton. What was that?
Mr. Richardson. Someone here has a mercury vapor sniffer.
Mr. Burton. Right. If they would like to come up here and
show us, we would like to have that.
Does the FDA take a position on the amount of mercury that
accumulates in the brain and whether or not it is easily
excreted from the brain?
Dr. Feigal. The toxicology of chronic implants, like alloy,
are looked at through a series of standards that evaluate
biomaterials. And most of the evidence that we evaluate
biomaterials with come from animal data and come from special
exposure studies in animals. Manufacturers are required to know
the toxicology profile of their products as part of the
controls that they have over their products. The risk is not
assessed in terms of any absolute amount or characteristic of
the toxicology, but in the context of the risk and benefits in
clinical use.
Mr. Burton. You were here for the previous panel.
Dr. Feigal. Yes.
Mr. Burton. You heard some of the researchers, the
scientists that testified who said that when you brush your
teeth, when you chew, when you have hot coffee or a hot
substance in your mouth vapors are emitted, and when you chew
some of it flakes off over a period of time and goes into your
body. Has there ever been a study done on cadavers, people that
have had a lot of fillings in their mouths to see what the
mercury content is in the brain, any studies that you know of?
Dr. Feigal. The studies that they cited are the same
studies that we reviewed in our process of looking at the
literature. How that relates to our classification is to look
at the product in actual use and to look at the risk and
benefit. All implants, including hip implants, jaw implants,
that are made of metal have metals that leech into the body,
plastic materials have volatiles, and we assess all of those
exposures. It is not a question of whether or not there is an
exposure. The question is whether there is adequate evidence
that the exposure causes clinical----
Mr. Burton. These other substances that you are talking
about, though, steel, plastic, they are not in the same class
as mercury, are they?
Dr. Feigal. There are problematic compounds that in very
low amounts--for example, there is cadmium in the alloys of hip
implants.
Mr. Burton. Cadmium, is that consistent with mercury as far
as toxicity?
Dr. Feigal. My point is that we----
Mr. Burton. No, is it? Is it as toxic as mercury to the
human body?
Dr. Feigal. It has to be put in the context of the level of
exposure and what the effect is and how that is offset by the
benefits.
Mr. Burton. Do you mean to tell me cadmium is as toxic a
substance as mercury? Is that what you are saying? Come on.
Dr. Feigal. What I am trying to do is put it in the context
of how FDA regulates products. We do not assess the
environment, we do not assess the effect of pure compounds and
absolute toxicity. We look at how they are used in practice.
Mr. Burton. You do agree though that mercury vapors leech
out of the tooth?
Dr. Feigal. Yes, we do agree with that.
Mr. Burton. And that it is ingested into the body?
Dr. Feigal. Yes, we do agree.
Mr. Burton. And it gets into the bloodstream?
Dr. Feigal. Yes.
Mr. Burton. And it goes to the brain and other organs of
the body?
Dr. Feigal. Yes, we agree with that.
Mr. Burton. And mercury has a cumulative effect in the
brain?
Dr. Feigal. That is less certain, but there is literature
on both sides. It is the clinical impact though that is the
standard for taking action on medical devices, not the
toxicology, not the ability to take preventive actions, but the
actual observed effects.
Mr. Burton. You know, I do not understand why--many people
in this country, probably the majority, do not know that there
is mercury in a silver filling in their mouth, in the amalgam.
Why doesn't the FDA at least, since mercury vapors do escape
into the mouth and into the body, why doesn't the FDA at least
make people aware of that? Why not publicize that?
Dr. Feigal. The FDA's authority on information about
products has to do with the labeling of products and only
rarely does the FDA actually directly intervene in the way that
products are described or presented in informed consent. That
is practice of medicine which the FDA is asked not to get
involved in.
Mr. Burton. What about the mercury in the vaccines, the
thimerosal and that sort of thing?
Dr. Feigal. I am afraid I will have to get followup from
someone else in the agency who can comment about vaccines. That
is outside my area.
Mr. Burton. Thimerosal contains mercury that is injected
into kids, and you heard me talk about that earlier.
Dr. Feigal. Yes.
Mr. Burton. I think that has been pretty well publicized,
hasn't it? Hasn't the FDA talked about that?
Dr. Feigal. Yes. But I think if you are talking about the
informed consent process----
Mr. Burton. I am not talking about informed consent. I am
just talking about making people aware.
Dr. Feigal. I think that is a reasonable request to do
that.
Mr. Burton. Then I would make that request, that the FDA
put a card or something in every dentist's office saying that
the amalgams that you get from your dentist contain
approximately 50 percent mercury, and then let the people make
the decision themselves. I think people ought to be held
accountable for their actions, but they at least ought to know
what the hell they are doing. And they do not.
Did you check that out? Ladies, did you check that out?
What did you find? Why don't you sit down there at the table,
Doctor, and give us that. What was the amount?
Mr. Richardson. They took a preformed pill-sized amalgam
filling that I suspect was prepared in Dr. Haley's lab, wiped
it with a napkin, and then held it to a Jerome mercury analyzer
to measure the mercury content in micrograms per cubic meter.
That device only measures the vapor. It does not measure
particulate or other forms.
They took three measurements. The first one was 283
micrograms per cubic meter, which is over 10 times the
threshold limit value for occupational exposure and some I
think about 100 times higher than the U.S. EPA reference
concentration. The second measurement, when it was held
slightly distant from the inlet to the device, came back at 82
micrograms per cubic meter. Again, that is approximately a
little more than double the threshold limit value. They then
polished it again, held it to the front of the device, and got
a number of 774 micrograms per cubic meter. With 25 micrograms
per cubic meter being the threshold limit value for
occupational exposure, that is some 5 times higher than the TLV
for the air that passed over that pre-made amalgam filling.
Mr. Burton. Doctor, come on up here. We will let you make a
comment on that. I do not want the American Dental Association
to feel left out.
You stick around up there. I want the FDA people to hear
this because that is why we asked them to be here is so they
could glean from the testimony some insights into what maybe
ought to be done.
Go ahead.
Dr. Mackert. OK. This instrument that was used is designed
for measuring mercury vapor in a room where the collection
volume, which is, depending on the model, 250 milliliters to
500 milliliters, the collection volume is small compared to the
volume of air of the room. Again, this is a matter that has
been studied extensively in the literature, particularly in
Sweden by a colleague of mine named Anders Berglund at the
University of Umea. This is not an appropriate use of this
instrument. I hope Dr. Richardson knows that this is not an
appropriate use of this instrument. To report micrograms per
cubic meter and then imply that a person inhaling mercury vapor
would be exposed to the levels that he described as if that
person were in a room with those concentrations, are you saying
that the person that would breath next to that would absorb the
same amount of mercury vapor as a person in a room with 280, or
whatever you just quoted, micrograms per cubic meter?
Mr. Richardson. No. All I was trying to do was put into
perspective the three measurements that were made by this
device. Agreed, in the context of if you were trying to
estimate exposure, you can in fact, and there have been studies
done, use that information in combination with information on
the size/shape of the oral cavity, the amount of air that is
inhaled with a breath, etc., to come up with estimates of
exposure.
Mr. Burton. Let me ask the people from the FDA something. I
asked the American Dental Association representative here who
is going to be on their decisionmaking board if they would
agree to do a study, take 100, 200, or 1,000 amalgams and split
them up and send them to different scientific research
laboratories, like Harvard or others, and have them tested
under heat and abrasion to measure the amount of mercury that
is emitted from these. Could the FDA participate or would they
participate? It does not sound like to me it would be that
costly. You just make the amalgams and you send them and they
would do the research. It does not seem like it would take a
rocket scientist to do that if you had the proper equipment.
Dr. Feigal. The FDA does relatively little funding of
research itself. It usually relies on the Public Health Service
and on the manufacturers or on other independent bodies to do
the research, or on standards bodies such as the International
Standards Organization or ANSI to develop standards. We would
welcome the results of such studies.
Mr. Burton. Can you not admonish somebody to do that? You
guys, come on, you are the ones that put the pressure on
supplements manufacturers and go in and raid them and
everything else to stop them from selling their supplements.
You do all kinds of stuff like that. Don't tell me you do not
have enough authority to kind of push them along to make them
do that. Why don't you do that?
Dr. Feigal. Well, believe it or not, Congress actually
wrote some authorities that we have to follow the rules. And in
devices, the logic would have to be that we would need that
information in order for the product to be used in a way that
would result in it being safe and effective. The way we have
looked at the review of the literature with the Public Health
Service is we have made the determination that the evidence to
date still comes down in the favor that these products are safe
and effective.
Mr. Burton. Dr. Tabak can do the study. He can do the
study.
Dr. Feigal. Yes.
Mr. Burton. He is a scientist who works in that area. But
you guys say because it does not come down on the side that you
agree with that no further studies are necessary.
Dr. Feigal. No I did not say that.
Mr. Burton. That is what I got from it.
Dr. Feigal. No. I apologize if I gave you that impression.
We welcome ongoing developments in the science. We can measure
mercury exposure levels, as you have heard, that we were never
able to measure in the past. And when we look at that
information and we say as a biomaterial is this still an
acceptable biomaterial, then we look at that both with animal
studies and with human studies and benchwork.
Mr. Burton. Have you done the kind of study I was just
talking about?
Dr. Feigal. As I understand it, you were asking to see what
the kind of exposure would be. But the context that we are
asked to regulate devices in, the context of risk and benefit,
and so we have to look at the two as they weigh together. We
would have to conclude in order to take an action that the
action was necessary for the product to be used safely and
effectively.
Mr. Burton. So what kind of a scientific research project
would you have to have that would give you that kind of
information?
Dr. Feigal. I think there are many different sources. I
think the ongoing development of the toxicology. Many of the
questions today where there were disagreements of conflicting
studies, it would be nice to get the animal work and the
benchwork about what is the level of exposure, the duration of
exposure. You heard that there was disagreement about the half-
life of materials in different parts of the body and what the
consequences of those are. We use the information from
epidemiology, we use the information from studies such as the
studies that Dr. Tabak described. It is a process that is
ongoing with us. So that when we feel that a risk has reached a
level where changing the classification or changing the
requirements by a manufacturer would make the product be used
more safely or more effectively, then we take those actions. So
we are constantly in the midst of that process. We just do not
fund it ourselves; we look at what everybody else does.
Mr. Burton. But you could, of course, urge this kind of a
study be done.
Dr. Feigal. Yes, we could, and we would probably do that in
the context of the Public Health Service, particularly given
the number of particularly small device firms.
Mr. Burton. Would you be willing to urge that amalgams in
some quantity be tested by leading scientific laboratories to
find out the amount of emissions?
Dr. Feigal. Yes, I would be willing to do that.
Mr. Burton. Would you do that. OK. Very good. We finally
got to where I wanted to go. [Laughter.]
Ben, do you have a question?
Mr. Gilman. Thank you, Mr. Chairman. Dr. Feigal, elsewhere
in the FDA mercury is not generally recognized to be safe, but
apparently the dental device division classifies dental mercury
as a Class I safe and effective device. Is that correct?
Dr. Feigal. That is correct.
Mr. Gilman. Why? Is that classification likely to stand, or
is it under review?
Dr. Feigal. We have proposed reclassifying it as a Class II
device. Again, the context of the risk is risk to the patient
in its use as a medical device. So it is not the same as risk
from food or risk from an environmental exposure.
Mr. Gilman. What are the differences in Class I, II, and
III dental devices? What are the differences?
Dr. Feigal. Class I devices are devices which require
general controls for medical devices, including registering and
listing the product, having a quality manufacturing system
which includes a mechanism of detecting adverse experiences in
a reporting system and reporting them to us, it includes
labeling requirements and other things, but it does not require
that the product be submitted to FDA for review prior to
marketing. There are a small number of Class Is but most of
them are exempt from pre-marketing.
Mr. Gilman. What about Class II?
Dr. Feigal. Class II, there are about 800 different Class
II products. Each of those has its own set of special controls.
The special controls are the controls that are necessary for
the product to be used safely, in addition to the controls the
Class Is have. So, for example, in the case of the alloy, there
is a range of materials that are allowed in alloys, a range of
amounts that have been developed by the American National
Standards Institute and by the International Standards
Organizations.
Mr. Gilman. And what about Class III?
Dr. Feigal. Class III is a group of products that must
demonstrate that they are safe and effective, and they usually
are products that have no comparable product that is on the
market or a product in which there is a substantial risk and
the only way to demonstrate the safety and the effectiveness of
the products is by performing clinical trials, usually prior to
marketing, although when a product is on the market at the time
of the amendments, they do not come off the market if they are
classified as Class III.
Mr. Gilman. So an amalgam with mercury in it is no problem
and that is why it is a Class I?
Dr. Feigal. No problem is--the Class I is the appropriate
level of regulation to have a well-manufactured product that
performs as intended and can be expected to be substantially
equivalent in safe and effective compared to other products.
Mr. Gilman. Do you have any reservations about the safety
and effectiveness in mercury being used as part of amalgam?
Dr. Feigal. The misconception I think about safety in FDA
is that we certify products as safe. We do not. All products
have risks. The question is is the risk----
Mr. Gilman. Does mercury have a risk?
Dr. Feigal. Of course it does.
Mr. Gilman. Then why is it a Class I?
Dr. Feigal. It is Class I for the same reason that medical
needles in shops are Class I, is it can be manufactured in a
way that it will perform in the way that it is expected and
will be safe and effective as its intended use. Just as some
forms of mercury are medical waste, used syringes are medical
waste.
Mr. Gilman. Tell me, I understand that the waste product,
the removal product is classified as a hazardous substance. Is
that correct?
Dr. Feigal. That is nothing that FDA has anything to do
with. It does not affect our risk classification at all.
Mr. Gilman. But it has been classified that way by EPA; is
that right?
Dr. Feigal. The vast majority of medical devices after they
have had human contact are classified as hazardous materials
and must be handled properly, according to the EPA.
Mr. Gilman. If it is a hazardous material, why isn't it
reclassified as a hazardous material for the dental community?
Dr. Feigal. The EPA classification is different than the
FDA classification. The FDA risk is risk to the patient as a
medical device. There are OSHA classifications on risks to
health personnel, there are EPA classifications on risk to the
environment. So there are things where a product will be in one
classification but not in another.
Mr. Gilman. So it can be a risk to the environment but not
to the patient, is that what you are saying?
Dr. Feigal. Absolutely. The vast majority of medical
devices waste are hazardous to the environment and must be
properly handled and incinerated.
Mr. Gilman. Doesn't that seem to be inconsistent in your
mind, that it is hazardous to the environment but not to the
patient?
Dr. Feigal. No, because it is in the context of use. A
needle is hazardous to the environment but it is not hazardous
to the patient. It is effective for what it is intended to do.
Mr. Burton. Would you yield for just 1 second.
Mr. Gilman. I am pleased to yield to the gentleman.
Mr. Burton. You heard the dentists talk earlier at the
first panel and they said mercury in the amalgam is toxic
before, and it is toxic after you take it out, so why isn't it
toxic or a problem when it is in the tooth?
Dr. Feigal. My understanding of that discussion was that
the toxicity was in terms of how EPA considered it in terms of
toxicity to the environment. That is a different issue than its
risk to the patient as a medical device.
Mr. Burton. If the gentleman would yield further. That
substance that is taken out of the tooth, that amalgam goes
into the water supply, into the sewage system, into everything.
And we know from you that we should not eat a lot of fish that
contain mercury. Where do you think that mercury comes from? It
does not come out of the air.
Dr. Feigal. The environmental issues are not the basis of
the FDA risk classification.
Mr. Burton. Do you guys ever talk to one another? I do not
understand it. If mercury is a toxic substance--Ben, thank you
for yielding--if mercury is a toxic substance, it is toxic
before it is put in the mouth and it is toxic afterwards, you
would assume that there is a modicum of risk while it is in the
mouth. You had the environmentalist there a while ago talking
about the horrible problem they are having with wastewater
treatment plants around the country and the water system, and
they are dumping huge amounts of these amalgams down the drain
because there is no regulation by FDA on what to do with it.
Why don't you regulate what to do with those things after the
dentist takes them out of the mouth so they do not get into the
ecological system?
Dr. Feigal. Because Congress has not given us the
jurisdiction to do that and they have given the jurisdiction to
the EPA and to OSHA. Another common example, for example, is
the use of radioactive substances in medical devices. Those are
hazardous products to the medical environment; they must be
handled in specific ways before use, they must be disposed of
carefully after use. But our risk classification would be to
classify their risk based on their use as a medical device.
OSHA, EPA, the State authorities would take care of the other
things. These have been divided.
Mr. Burton. Let me just make one more comment and then I
will yield back to my colleague. You know, because of the
threat to the security of America, we are combining a whole
bunch of agencies into what they call Homeland Security. It
sounds to me like we ought to do that with the health agencies.
We ought to take EPA and the health agencies and everybody else
and put them under one governing body so that you guys work
together.
If there is an amalgam that is dangerous before and
dangerous afterwards to the environment, and I believe it is
dangerous to the person, it seems to me there would be a
consistency of thought. And it does not sound like there is.
You guys are saying the amalgam is not a threat to the person,
at least not in your opinion right now, the merits outweigh the
problems with it, and yet before and after it is a problem for
the ecology and the environment. There is an inconsistency
there that just alludes me.
Dr. Feigal. There are countries, Singapore is an example,
where the EPA and the FDA functions are in the same
organization. But that is not how we have been organized.
Historically, actually much of the staff of EPA was drawn from
FDA at the time President Nixon created the EPA. The functions
were separated and made different.
Mr. Burton. Ben.
Mr. Gilman. Thank you, Mr. Chairman. Dr. Feigal, how do you
explain the extraordinary variance between the amalgam's vapor
release rates between the various researchers, as illustrated
by Dr. Haley, Richardson, and Fischer?
Dr. Feigal. Again, we do not dispute the fact that there is
exposure to mercury. The question is whether or not mercury as
a medical device still has benefits that outweigh the risk and
whether or not the product meets the standards that we look at
for a biomaterial in terms of its toxicity.
Mr. Gilman. What are the benefits of mercury usage?
Dr. Feigal. The benefits of dental amalgam would be a
question better answered by Dr. Tabak or one of the dentists.
But the question is it effective as a dental restorative
device, I think that probably has not been one of the things
that has been questioned.
Mr. Gilman. Based on today's standards at the FDA, if
mercury amalgams were new and were submitted for approval as a
dental device using the existing published research, would it
be approved?
Dr. Feigal. That is a very good question. I have actually
thought a lot about that.
Mr. Gilman. I am pleased to hear that.
Dr. Feigal. The products that are already on the market,
the burden of proof is on the agency to demonstrate that the
risks are high enough to take them off the market. And the
standard is so high that in 27 years only one product has been
banned and no product has been involuntarily withdrawn from the
market because of safety concerns by FDA because of the very
high standards for demonstrating the evidence that has been
placed on the agency through the Food, Drug, and Cosmetic Act
and the device amendments. It is not our choice, it is the way
that it was set forward.
Now a new product coming onto the market would actually
have to show as safe and effective before it was on the market.
And if we start by saying we assume that its properties as a
restorative material would be relatively easy to demonstrate,
so it would meet the effectiveness standard relatively easily.
So the question is if it were a new substance, what would they
have to do to show it was safe. And there they would have to
meet recognized international scientific standards on the
toxicology of the substance, to show that, in fact, the way it
was used that the toxicity was not a problem. It would not be
an issue of whether there was toxicity or not, it is whether or
not in the context of the use you could actually demonstrate
risk. The kinds of studies that Dr. Tabak has done would be the
kinds of studies that would be looked at, where you would have
a very careful look at a group that was exposed and not exposed
to look for clinical effects. We would also rely on animal work
and on what is known about the physical properties of the
materials.
But that is one of the differences. The old products, the
assumption made in the device amendments was the old products
were safe and new products to come onto the market only had to
be shown to be substantially equivalent to a product on the
market in 1976. That is the legal standard in the law. For the
Class III products newly coming onto the market, products must
show that they are safe and effective.
Mr. Gilman. Dr. Feigal, if you were to deny the use of
mercury in an amalgam for dentists, what harm would that do to
the practice of medicine?
Dr. Feigal. We would have to actually do that based on the
legal tools given to us in the statute, and the statute
requires a very high demonstration of harm, not to answer the
question of whether it would be a reasonable precaution. The
statute would require that to ban a product we would actually
have to show the damage that the product was causing in use as
a medical device.
Mr. Gilman. Do you have any evidence to either support or
refute Dr. Haley's statement that, ``The data regarding the
specific ability of mercury to cause much of the aberrant
biochemistry found in the brain and to produce many of the
widely accepted diagnostic hallmarks of Alzheimer's disease is
unquestionable.'' He said it is unquestionable. How do you
respond to that?
Dr. Feigal. I think part of the discussion that occurred
during the first panel was whether or not that was a view that
was widely accepted. We looked at the balance of evidence
across different scientific experts and studies and we would
have to consider that an interesting hypothesis but something
which is unproven. There are also concerns about the issue of
aluminum in Alzheimer's disease and other types of exposures,
and we need to look at all of those types of issues. But I do
not think there is a scientific consensus that agrees with Dr.
Haley at this point in time, would be my assessment.
Mr. Gilman. So you disagree with Dr. Haley's findings?
Dr. Feigal. Looking at it in the balance of the rest of the
data and research on Alzheimer's disease, I can speak for the
process of looking at this, but we would probably not agree
with him at this time.
Mr. Gilman. Again, with regard to the use of mercury, in
your testimony you state that amalgam as a restorative is used
to treat dental caries. Is that correct?
Dr. Feigal. That is correct.
Mr. Gilman. But that actually is not true, is it? You are
not treating a cavity. The dentist drills out the cavity and
fills in the gap with the amalgam. You do not actually treat it
or cure it. You clear it out and fill in the gap. So what would
be the harm in filling in the gap without mercury?
Dr. Feigal. There are multiple products that can be used
the way that amalgam is used, and the way you describe it is a
correct characterization of how it is used. The FDA standard,
the standard that is in the Act for products to be on the
market is not that they should be removed from the market if
there is a better alternative. The standard is that they are
safe and effective for use.
Mr. Gilman. Are there better alternatives?
Dr. Feigal. There are alternatives with other advantages
and disadvantages.
Mr. Gilman. Are there better alternatives than using
mercury in the amalgam?
Dr. Feigal. Perhaps you should ask Dr. Tabak.
Mr. Gilman. Dr. Tabak.
Mr. Tabak. There are alternatives, sir, but not
substitutes.
Mr. Gilman. The question is, are there better alternatives
than using mercury in amalgams?
Mr. Tabak. Currently, in some clinical conditions, no.
Mr. Gilman. And what are those conditions?
Mr. Tabak. If you have extensive damage to the tooth, there
are situations where you cannot restore it with a material such
as a composite restoration, which is most often referred to as
the alternative restorative material.
Mr. Gilman. And you say there are no materials that could
be utilized except a mercury amalgam?
Mr. Tabak. As was indicated in the first panel, sir, you
can use a gold restoration which carries with it a very high
cost.
Mr. Gilman. But it is available?
Mr. Tabak. It is available.
Mr. Gilman. And it is a better usage than a mercury
amalgam, is that correct?
Mr. Tabak. I would not say it is better, sir. I would say
that it is an alternative.
Mr. Gilman. Is it a preferable alternative?
Mr. Tabak. I would not say it is preferable, sir. I would
say it is an alternative.
Mr. Gilman. Thank you. Thank you, Mr. Chairman.
Mr. Burton. Chairman Gilman asked one question, Dr. Feigal,
that you kind of skirted around. I want to get a more
definitive answer. Based on today's standards at the FDA, if
mercury amalgams were new and were submitted for approval as a
dental device, using the existing published research today,
would you approve it?
Dr. Feigal. I think we would approve it as a restorative,
yes I do.
Mr. Burton. Do you. And what class of device would you call
it?
Dr. Feigal. It would still probably be a Class II device
because most of the evidence would not have to come from
clinical evidence.
Mr. Burton. Now after you do that study I asked you about a
while ago, if it shows that there is an inordinate amount of
vapor leeching into the body, would you maybe reconsider?
Dr. Feigal. What we would have to know is what the
significance was of the release of the vapor. And it comes back
to the point I must not have made very clearly before, which is
it is not the exposure which is at issue, it is the clinical
significance of the exposure. That is what needs to be
established.
Mr. Burton. Man, I do not want to breath mercury vapors. Do
you? Do you like breathing mercury vapors?
Dr. Feigal. I would prefer not to.
Mr. Burton. But you put them in your mouth. And if you have
an inordinate amount of mercury vapor leeching out because you
brush your teeth, because you eat something, because you drink
hot coffee, would that not be of concern, especially when you
know it has a cumulative effect in the brain? Do you mean that
does not even concern you? You are a scientist, a doctor.
Dr. Feigal. It is also of concern to me not to be exposed
to x-rays, and yet I still----
Mr. Burton. I am not talking about x-rays.
Dr. Feigal. But I still watch my television set. If we were
to say why take the risk----
Mr. Burton. But you sit further back, you do not sit right
up on top of it.
Dr. Feigal. There is still exposure. Why should I have any
exposure?
Mr. Burton. I am talking about mercury. I am not talking
about your television set.
Dr. Feigal. The issue is the same. We have to know at what
level the exposure actually has clinical significance.
Mr. Burton. That is what I am asking about in this study.
If you find that there is an inordinate amount of exposure from
the emission, do you think you might reevaluate that?
Dr. Feigal. If the exposure was known to be clinically
significant, then we would change, yes.
Mr. Burton. I hope you will allow our colleague that has
done extensive research on this to be part of that research
project that you are going to recommend.
Dr. Feigal. We are always happy to look at all sources of
evidence.
Mr. Burton. I am going to send you a letter after the
hearing that says you said you thought you could do this and I
am going to suggest that you have him as part of the research
project. I would be very happy to take a look at the results
next year because I am probably going to be very active in this
next year as well and maybe we can talk again.
Dr. Mackert. Mr. Chairman, I wonder if I could----
Mr. Burton. Did you have a question? Yes, please.
Dr. Mackert. I wonder if I could make a comment on your
question about the release of materials into the body from
amalgam and other materials.
Mr. Burton. Yes.
Dr. Mackert. I have studied dental materials for 24 or 25
years, all different materials. I work in ceramics, every
material that we use in the body releases elements into the
body and those are absorbed into our body. And if we look,
there is gold in the tissue under my ring here. That is on the
same order of magnitude as the mercury that would be in my gum
tissue next to my filling.
Mr. Burton. Toxicity?
Dr. Mackert. Gold is a very toxic element.
Mr. Burton. It is as toxic as mercury?
Dr. Mackert. If the dose is the same, the toxicity is
similar.
Mr. Burton. So if I have a gold cap on my tooth and I have
a mercury filling, they are both the same?
Dr. Mackert. In terms of the effect on you? Both of them
have no effect on you. But let me just ask a question of you,
if I may.
Mr. Burton. Oh, sure. If I do not know, I will just tell
you.
Dr. Mackert. I do not know what materials you had your
amalgams replaced with.
Mr. Burton. A composite. My dentist is right there.
Dr. Mackert. Did the dentist tell you the ingredients of
that composite before you put it in your mouth?
Mr. Burton. Sure, he told me.
Dr. Mackert. What were the ingredients?
Mr. Burton. I do not remember. Tell him.
Dr. Mackert. Did he tell you about the allergenicity of the
hydroxy ethyl-methacrylate that is used as a bonding agent? It
is one of the most potent allergens used in dentistry. Bob
Erickson, who is the pride----
Mr. Burton. And it is as toxic as mercury?
Dr. Mackert. It is an allergin. It causes an adverse health
effect. What I am saying is that if we remove materials just
because they have the potential of causing adverse health
effects in certain small groups of people, we will not have
anything. I had a patient call me 2 weeks ago who was
distressed because she wanted to have her amalgams replaced and
she wanted to know even a temporary material that she could put
in until she could make a decision. I told her some of the
options, and she's, well, no, that has zinc in it, that has
this in it. She was concerned about everything. And this is
what I am concerned about as a dentist is that people become so
frightened because of alarmist predictions that they cannot
make a decision about----
Mr. Burton. I have allowed you a lot of latitude because
you do represent the ADA.
Dr. Mackert. Thank you.
Mr. Burton. So I am going to allow our people who have a
contrary point to view to respond. Go ahead.
Mr. Richardson. I would agree that risk assessments of
dental materials are sorely needed. When I completed my work on
dental amalgam, the question was raised, well, we know more
about amalgam now than anything else, if we ban it do we jump
out of the frying pan into the fire? And I looked around and
there was not a single thing written in the published record on
the risks of any other materials.
I approached the CDA. They refused to fund any work on risk
assessment. I approached Health Canada and they refused to fund
any work on risk assessment. The IAOMT funded my work to assess
the risks posed by composite resin materials following the
exact same procedures used that I applied to dental amalgam.
The exposures to the components of composite resins that occur
from having 25 fillings of composite resin material are
hundreds to thousands of times below the U.S. EPA safe or
reference doses for those materials.
I submitted that work to a dental journal for publication
because it seemed to me that it would be in the interest of the
dental community to know it, and, yes, it was rejected out of
hand because the name Mark Richardson was attached to it. It
was gobbled up by a peer reviewed journal that is dedicated to
human and ecological risk assessment, a journal that is
published here in the United States.
It is unfortunate that there are still no risk assessments
going on on any other materials. There has not been one
published on gallium, which was investigated as a possible
replacement for amalgam, there has never been a risk assessment
done on gold, and, in fact, gold is one of the most safe metals
that you can be exposed to. Where this information comes from,
I would love to see the literature, the risk assessments that
appear to have been done on these materials because they are
not published anywhere. That is all I have to say.
Mr. Burton. Just 1 second. Why has there not been risk
assessments done on all these materials?
Dr. Feigal. There are actually assessments done on the
materials, the Bead National Toxicology Standards. These are
set by the International Standards Organization on Toxicology.
Much of the material in manufacturing is proprietary
information. It is----
Mr. Burton. You guys are supposed to make sure that the
things they put into our bodies are safe. And you are now
telling me that it is proprietary, so you do not know?
Dr. Feigal. We review it. The fact that certain material is
not released is, again, a creation of Congress.
Mr. Burton. Well if you are comparing it, if you are
finding out if there is a toxic substance in there, shouldn't
that be made known to the public? Proprietary interests should
not take precedence over what the public should know.
Dr. Feigal. We release the information which legally is not
a trade secret. That is all defined by law and by statute. We
release that information. It is our responsibility to review
the information, and if there is not adequate information, to
not release the product.
Now one of the concerns that is raised is not so much on
the short acute exposure but on the long-term exposure. There
is no way to actually cut short the fact that if you have got a
material that has been used for 5 years, you do not know the
10-year or the thirty year effect. And that is something that
we have to live with all the time with new materials. There is
no way to test something for 30 years before you use a new
material.
So we look at the acute effects, we look at exaggerated
dosing. Most of the material done on alloys, on materials have
intellectual property protections, have trade protections
provided by Congress that does not protect them from showing it
to us but does create the kinds of frustrations that exist in
the community of saying we do not know much about these.
Mr. Burton. There needs to be a modicum of trust between
the Federal Government and the people. And if there are
questions about whether or not something might or might not be
harmful to an individual, proprietary rights, there has got to
be some way around that. He said that these things have not
been categorized or checked and you are saying, well, we look
at them.
Dr. Feigal. We do, and we actually----
Mr. Burton. I know, you say we look at them, but because of
proprietary interest we cannot let the public know about them.
You know, the problem is the trust factor. People want to know
that they can trust their government. And when some things that
happen in the health agencies that shows that there is a
problem, they want to know, especially things they are putting
into their body.
Dr. Feigal. That is right. I would agree with that. And I
would say that the responsibility you have given us is to keep
those things from being used. And one of the things that is
written in the statute that could be changed, it is in the
current statute, is that when we turn a company down for a
request to use a certain material, that information cannot be
released. It cannot be released even that they have requested
it or the basis for our turning it down. So there are certain
things that are built into the current framework that I think
could be addressed and say is this the way we want to do
business at this point.
Mr. Burton. If you have recommendations on things that
should be changed so that the public can be better informed,
let me know and I will help carry the mail for you.
Mr. Gilman.
Mr. Gilman. Thank you, Mr. Chairman. I want to be clear on
something you have said. You have tested these amalgams. You
have made up a list of those that are bad and those that are
good apparently. Is that correct?
Dr. Feigal. We actually do no testing ourselves at FDA, or
a relatively small amount because we have a very small
laboratory.
Mr. Gilman. Who does the testing?
Dr. Feigal. All the testing is done by manufacturers and
they do it in accordance with international standards that are
set by international standards bodies. So in this case, the
standards for alloys are set by the American National Standards
Institute and by the International Standards Organization, ISO.
Mr. Gilman. So there is no testing by any public agency?
Dr. Feigal. No, there is not, nor is there of drugs, nor is
there of foods that come to market. That is not the standard.
There are 500,000 different devices on the market in the United
States. We approve 40 to 50 devices a day in this country.
Mr. Gilman. What do you base your approval on?
Dr. Feigal. We base it on having a risk-based approach, so
that the highest risk products must show safety and
effectiveness with clinical trials, the medium risk----
Mr. Gilman. But how do you know the safety and
effectiveness if you are not doing the testing? Are you relying
on the manufacturer?
Dr. Feigal. For drugs, for devices, and for biologics, we
rely on the manufacturer's testing. We inspect. We have severe
punishment and penalties for companies that falsify information
and do not release everything to us.
Mr. Gilman. How do you know whether it is an accurate
assessment if you are not testing it?
Dr. Feigal. We do not retest. We do not have the tens or
hundreds of billions of dollars that are spent every year by
the device community testing their devices. We set the
standards by which they test the medium and high risk devices,
they present that data to us and we inspect the data and we
inspect their facilities.
Mr. Gilman. That is like leaving the fox in the chicken
coop to do the policing.
Dr. Feigal. It would be if we allowed them to self-certify.
But because we review their raw data, which no other country in
the world does, we are the only country that goes in and
inspects the raw data, it----
Mr. Gilman. Let me ask you, Doctor. Don't you think it
would be more important for the association, your agency to do
the testing rather than to allow that testing to be done by the
manufacturer?
Dr. Feigal. We would then need to have a testing facility
of the same magnitude of the testing facilities of the
manufacturers in aggregate. They currently spend billions of
dollars doing this.
Mr. Gilman. I am asking, do you think it would be more
important for the agency to do the testing rather than the
manufacturers?
Dr. Feigal. Quite frankly, I do not think the Government
could do it as quickly as the private sector.
Mr. Gilman. I am not talking about the expedited testing. I
am talking about the importance of the agency to do the
testing.
Dr. Feigal. In terms of doing all testing, no. We have to
be able to inspect what the manufacturers are doing as they
manufacture. It is not just even the issue of meeting the
standards at the time of approval, it is also the standards
when they are manufacturing. So if the logic was that we would
have to do all of the testing, we would also have to do all of
the testing of their ongoing manufacturing.
Mr. Gilman. Would that not be more beneficial to the
public?
Dr. Feigal. Only if we had the resources that industry has.
And I testified----
Mr. Gilman. If you had the resources, would that be more
beneficial to the public for your agency to do the testing?
Dr. Feigal. I would seriously doubt if a single agency
based in one location, funded on an annual basis in the way
that Government manages to run itself could actually compete
with the private sector in terms of producing quality products.
Mr. Burton. There are advisory panels over at the FDA and
the health agencies who are supposed to do what we call double
blind studies and check all that stuff out before you put it
into the marketplace.
Dr. Feigal. The advisory panels review the evidence as
well. But the thing which is unique about both our relationship
and the advisory panels in the world is our ability to request
all the data and the raw data, and that is what gives us the
ability to make sure that the studies are done properly.
Mr. Burton. Ms. Watson.
Ms. Watson. Thank you, Mr. Chairman. I must apologize for
not being here throughout the hearing. If I become redundant,
would you please let me know.
I am sorry that Dr. Mackert left the room. I wanted to be
sure I heard him correctly. And so I am going to try to restate
what he said and maybe you two gentlemen can confirm. I think I
heard him say that there is no risk to mercury in the dental
amalgam. Is that what he said?
Mr. Tabak. I cannot speak for him. I do not know.
Ms. Watson. Did you hear him?
Mr. Tabak. I think that is what he said, yes, Ms. Watson.
Ms. Watson. OK. Would you two gentlemen confirm that?
Mr. Tabak. There is no scientific evidence to indicate that
there is a risk.
Ms. Watson. Is that your response to his statement?
Mr. Tabak. Yes, it is. That is correct.
Ms. Watson. OK. The word ``amalgam'' itself is part of the
meaning of the word ``amalgam with mercury,'' yes or no?
Mr. Tabak. Indeed it is.
Ms. Watson. Is mercury toxic?
Mr. Tabak. Elemental mercury is toxic.
Ms. Watson. Is mercury toxic?
Mr. Tabak. Elemental mercury is toxic.
Ms. Watson. Would you answer my question. Is mercury toxic?
Mr. Tabak. I am trying to give you a correct answer.
Ms. Watson. Is it yes, no.
Mr. Tabak. Yes.
Ms. Watson. Thank you. Now is silver mercury? Does it
contain mercury? Yes or no. Silver amalgam fillings, does it
contain mercury?
Mr. Tabak. It does.
Ms. Watson. Yes. Almost up to 50 percent?
Mr. Tabak. Yes.
Ms. Watson. OK. Now you scientific people are doctors. I
think, Dr. Feigal, you are an M.D.?
Dr. Feigal. Yes.
Ms. Watson. To do no harm, what would you have against
advising dentists to advise their patients that an amalgam with
mercury is what we call silver, it is an amalgam, it is not
pure silver, what would you have against it?
Dr. Feigal. No problem at all.
Ms. Watson. All right. Would you advise that we then say to
dentists you should inform your patients?
Dr. Feigal. Yes.
Ms. Watson. OK. Now we all agree that mercury is a toxic
substance. Would both of you agree?
Mr. Tabak. It depends on the level of exposure.
Ms. Watson. Let me repeat. Regardless of the level, poison
is poison.
Dr. Feigal. That is not true. Digitalis is an effective
drug on one level and a poison on another.
Ms. Watson. Hold on, sir. Mercury is a toxic substance.
Agreed?
Dr. Feigal. Not in all uses, not in all settings.
Ms. Watson. OK. I want what you just said given to me. So
whoever is recording this, I want to be sure I can quote you
correctly.
Now would you agree that once you have a silver filling,
mercury amalgam filling, that it emits a vapor as long as it is
within your mouth. Is that a true statement?
Dr. Feigal. Yes.
Mr. Tabak. Yes.
Ms. Watson. All right. If we know that, why is it a
medically trained person, a dentist would not want to share
that with the patient. Doesn't the patient have a right to
know. I, as a legislator, and my colleagues are here to protect
the public and we speak for the public. Why is it that the ADA
will not tell the public that mercury amalgam is harmful but
they can choose to have it in their fillings. Now can you
explain that to me?
Dr. Feigal. Well, you started by saying should patients be
told that the product contains mercury, and should we admit
that we know there is exposure from vapor release. I think
those are appropriate things to discuss. And I think patients
should be informed that the evidence on the health risk is
something that is actively being studied as we speak, even in
studies by the National Institutes of Health. Where it gets
more difficult is asking a patient to understand what does it
mean to have a small amount of mercury release, just as it is
hard for them to understand what their risk is from other low
level exposures.
So I think we need to actually think about the message that
we are trying to get. I think the patient should be informed.
But it is similar to the question about the composites and
about the effect of what is the long-term effect of having a
substance like methyl-methacrylate in your mouth and what is
known about that. I think there does need to be a much more
informed and empowered consumer and they need to be able to
make the choice.
I suspect where there is a difference in where we may being
agree to disagree----
Ms. Watson. Would you yield for a minute?
Dr. Feigal. Sure.
Ms. Watson. That is exactly what this bill is trying to do.
We would like you, as representatives of the dental profession
or researchers, or whatever, to educate. I asked in my bill of
10 years ago in the State of California for a protocol. We
never got it because the panel was controlled by dentists. I
was told by the dentists that they did not want to scare off
their patients, and that it was cheaper to use a mercury
amalgam or a dental amalgam, or silver, whatever they want to
call it, than the alternative. So because it was cheaper, they
did not want to inform their patients. I was appalled at that
response coming from a medical professional. I am appalled with
what I have heard here this afternoon. You do not want to
answer my questions directly. Why do you think a patient would
not listen to the doctor if a doctor had a protocol which
explained what was in that silver. Why are we continuing to
delude people by saying you have a silver filling in your mouth
when we know we are not telling them the truth.
We had to research paint because we found that babies were
chewing on the railings of their bassinets and it was very
poisonous to their system. We did long-range studies, long-term
studies and found out that those children were having
difficulty in schools when they got to school. Asbestos, which
was a certified building material, we found out it was a
carcinogen, long-term studies. Why could we not do long-term
studies on mercury at any trace amount, trace, I say, amount.
And you just agreed that over a period of time it does seep out
and has a vapor. Why would we want to delude people by not
telling them. So that is what the bill does.
The other thing that I am appalled at is that you would not
say we need to do the studies, we need to look at the risk,
because we think that if mercury is going to be taken out of
thermometers, if mercury is going to taken out of other
products, that it is still all right to use it in someone's
mouth. I do not understand your----
Dr. Feigal. The question to me was should FDA do the
studies, and FDA does not do studies except for very small
parts. We welcome the studies that are done, we encourage them,
and we review the results.
Mr. Burton. If the gentlelady would yield just a second.
Dr. Feigal very graciously agreed earlier that he would--I
think I am quoting you correctly--that you would----
Dr. Feigal. Urge.
Mr. Burton. Urge. I urged you and you said you would accept
the urging, or words to that effect. But he would urge some of
the outside scientific research facilities to take amalgams,
maybe 100, 200, or 300, and have them checked to find out the
amount of emissions of mercury vapor that is coming out over a
period of time. I also urged that Dr. Haley be a part of that
study because he has some expertise in the area.
Ms. Watson. Great.
Mr. Burton. So they have, in essence, agreed that they
would work with us on that.
Ms. Watson. Thank you. I do not want to be redundant. Let
me just ask one more question. I understand that the
manufacturers of products do the research, and I understand
that you said you do not have the capacity comparably to do the
research. Can someone respond to why the FDA has not required
the manufacturers to show the health effects of what you have
agreed to is the mercury vapors. Can someone respond?
Dr. Feigal. These were products that were on the market in
1976 when the Device Amendments were passed. And for FDA to
take an action about safety, actually the burden falls to the
Government, not to the manufacturer, to present the evidence
that a product needs to be up-classified or an adverse action
taken against it. And so this is an area where, because this is
a product that was on the market, the burden of proof is on us.
Now the way we approach that is not do the studies
ourselves but to review the scientific literature, most of
which in this area, quite frankly, is not done by the
manufacturers. One of the things to remember about the device
industry is that of the 12,000 firms, half of them have five or
fewer employees; 92 percent of them qualify or meet the
Commerce Department's definition of a small business. And as
Congress looked at how do you regulate an industry that makes
so many products and makes 500,000 different products, they
gave us the responsibility of doing it in a risk-based fashion,
starting with the assumption that most of the things on the
market were on the market because they were proven products.
And there are products which have been up-classified and which
we have called for the highest levels of evidence for. But as
we have gone through the process of reviewing the literature,
it has been very difficult for us to say we think mercury is
causing Alzheimer's disease, or we think the evidence shows
that mercury is causing the other kinds of things.
Ms. Watson. Would you yield, please?
Dr. Feigal. Sure.
Ms. Watson. I am not trying to tell you what the outcomes
would be of your studies. But I am just wondering why you have
not done them in the past. And I surely would have thought you
would consult with Dr. Richardson. I just heard him here for a
minute and he has done some of this risk assessment and he says
that his results were not even considered. And so it seems as
if there has been research and studies done, but apparently not
at the scholarly or empirical level that FDA would want to be
concerned with. I have difficulty understanding why the FDA has
never classified mercury fillings.
That is the reason why this bill is here, do you understand
that, because we had dentists dragging their feet, and they
finally told me why. So we just got rid of the panel and we put
people on there that are really concerned about the public's
health. And by your own admission, vapors are emitted as long
as there is mercury in the amalgam. I think that would be
enough to tip you off that you ought to classify, you ought to
do the research, you ought to do it yourselves.
Therefore, we are going to help you out. We have a bill
here, and I am thinking about amending it, Mr. Chair, to put in
a required study and maybe some dollars to back it up. So as
this bill moves, we are going to look at an amendment. So we
are going to do your work for you. We are going to direct you.
Because our first and foremost interest is protecting the
health of the public. And if one person is injured by something
they thought was silver and the dentist did not say it was
mercury but silver, then you are deluding the public and we are
not going to stand for that. So this bill is here because we
are interested in the health of every single American.
I want to thank you, Mr. Chairman, for holding these
hearings. I will turn it back to you.
Mr. Burton. Thank you, Ms. Watson.
Mr. Gilman, do you have any more questions?
Mr. Gilman. No questions.
Mr. Burton. I know you have been here for a long time. I
want to thank you very much for your patience, all of you in
the first panel and the second panel. I am going to see you
again to make sure I get the rest of the amalgams out of my
mouth.
I want to thank John Rowe and Beth Clay for their hard work
on the hearing.
With that, we stand adjourned.
[Whereupon, at 2:43 p.m., the committee was adjourned, to
reconvene at the call of the Chair.]
[Additional information submitted for the hearing record
follows:]
[GRAPHIC] [TIFF OMITTED] T4699.079
[GRAPHIC] [TIFF OMITTED] T4699.080
[GRAPHIC] [TIFF OMITTED] T4699.081
[GRAPHIC] [TIFF OMITTED] T4699.082
[GRAPHIC] [TIFF OMITTED] T4699.083
[GRAPHIC] [TIFF OMITTED] T4699.084
[GRAPHIC] [TIFF OMITTED] T4699.085
[GRAPHIC] [TIFF OMITTED] T4699.086
[GRAPHIC] [TIFF OMITTED] T4699.087
[GRAPHIC] [TIFF OMITTED] T4699.088
[GRAPHIC] [TIFF OMITTED] T4699.089
[GRAPHIC] [TIFF OMITTED] T4699.090
[GRAPHIC] [TIFF OMITTED] T4699.091
[GRAPHIC] [TIFF OMITTED] T4699.092
[GRAPHIC] [TIFF OMITTED] T4699.093
[GRAPHIC] [TIFF OMITTED] T4699.094
[GRAPHIC] [TIFF OMITTED] T4699.095
[GRAPHIC] [TIFF OMITTED] T4699.096
[GRAPHIC] [TIFF OMITTED] T4699.097
[GRAPHIC] [TIFF OMITTED] T4699.098
[GRAPHIC] [TIFF OMITTED] T4699.099
[GRAPHIC] [TIFF OMITTED] T4699.100
[GRAPHIC] [TIFF OMITTED] T4699.101
[GRAPHIC] [TIFF OMITTED] T4699.102
[GRAPHIC] [TIFF OMITTED] T4699.103
[GRAPHIC] [TIFF OMITTED] T4699.104
[GRAPHIC] [TIFF OMITTED] T4699.105
[GRAPHIC] [TIFF OMITTED] T4699.106
[GRAPHIC] [TIFF OMITTED] T4699.107
[GRAPHIC] [TIFF OMITTED] T4699.108
[GRAPHIC] [TIFF OMITTED] T4699.109
[GRAPHIC] [TIFF OMITTED] T4699.110
[GRAPHIC] [TIFF OMITTED] T4699.111
[GRAPHIC] [TIFF OMITTED] T4699.112
[GRAPHIC] [TIFF OMITTED] T4699.113
[GRAPHIC] [TIFF OMITTED] T4699.114
[GRAPHIC] [TIFF OMITTED] T4699.115
[GRAPHIC] [TIFF OMITTED] T4699.116
[GRAPHIC] [TIFF OMITTED] T4699.117
[GRAPHIC] [TIFF OMITTED] T4699.118
[GRAPHIC] [TIFF OMITTED] T4699.119
[GRAPHIC] [TIFF OMITTED] T4699.120
[GRAPHIC] [TIFF OMITTED] T4699.121
[GRAPHIC] [TIFF OMITTED] T4699.122
[GRAPHIC] [TIFF OMITTED] T4699.123
[GRAPHIC] [TIFF OMITTED] T4699.124
[GRAPHIC] [TIFF OMITTED] T4699.125
[GRAPHIC] [TIFF OMITTED] T4699.126
[GRAPHIC] [TIFF OMITTED] T4699.127
[GRAPHIC] [TIFF OMITTED] T4699.128
[GRAPHIC] [TIFF OMITTED] T4699.129
[GRAPHIC] [TIFF OMITTED] T4699.130
[GRAPHIC] [TIFF OMITTED] T4699.131
[GRAPHIC] [TIFF OMITTED] T4699.132
[GRAPHIC] [TIFF OMITTED] T4699.133
[GRAPHIC] [TIFF OMITTED] T4699.134
[GRAPHIC] [TIFF OMITTED] T4699.135
[GRAPHIC] [TIFF OMITTED] T4699.136
[GRAPHIC] [TIFF OMITTED] T4699.137
[GRAPHIC] [TIFF OMITTED] T4699.138
[GRAPHIC] [TIFF OMITTED] T4699.139
[GRAPHIC] [TIFF OMITTED] T4699.140
[GRAPHIC] [TIFF OMITTED] T4699.141
[GRAPHIC] [TIFF OMITTED] T4699.142
[GRAPHIC] [TIFF OMITTED] T4699.143
[GRAPHIC] [TIFF OMITTED] T4699.144
[GRAPHIC] [TIFF OMITTED] T4699.145
[GRAPHIC] [TIFF OMITTED] T4699.146
[GRAPHIC] [TIFF OMITTED] T4699.147
[GRAPHIC] [TIFF OMITTED] T4699.148
[GRAPHIC] [TIFF OMITTED] T4699.149
[GRAPHIC] [TIFF OMITTED] T4699.150
[GRAPHIC] [TIFF OMITTED] T4699.151
[GRAPHIC] [TIFF OMITTED] T4699.152
[GRAPHIC] [TIFF OMITTED] T4699.153
[GRAPHIC] [TIFF OMITTED] T4699.154
[GRAPHIC] [TIFF OMITTED] T4699.155
[GRAPHIC] [TIFF OMITTED] T4699.156
[GRAPHIC] [TIFF OMITTED] T4699.157
[GRAPHIC] [TIFF OMITTED] T4699.158
[GRAPHIC] [TIFF OMITTED] T4699.159
[GRAPHIC] [TIFF OMITTED] T4699.160
[GRAPHIC] [TIFF OMITTED] T4699.161
[GRAPHIC] [TIFF OMITTED] T4699.162
[GRAPHIC] [TIFF OMITTED] T4699.163
[GRAPHIC] [TIFF OMITTED] T4699.164
[GRAPHIC] [TIFF OMITTED] T4699.165
[GRAPHIC] [TIFF OMITTED] T4699.166
[GRAPHIC] [TIFF OMITTED] T4699.167
[GRAPHIC] [TIFF OMITTED] T4699.168
[GRAPHIC] [TIFF OMITTED] T4699.169
[GRAPHIC] [TIFF OMITTED] T4699.170
[GRAPHIC] [TIFF OMITTED] T4699.171
[GRAPHIC] [TIFF OMITTED] T4699.172
[GRAPHIC] [TIFF OMITTED] T4699.173
[GRAPHIC] [TIFF OMITTED] T4699.174
[GRAPHIC] [TIFF OMITTED] T4699.175
[GRAPHIC] [TIFF OMITTED] T4699.176
[GRAPHIC] [TIFF OMITTED] T4699.177
[GRAPHIC] [TIFF OMITTED] T4699.178
[GRAPHIC] [TIFF OMITTED] T4699.179
[GRAPHIC] [TIFF OMITTED] T4699.180
[GRAPHIC] [TIFF OMITTED] T4699.181
[GRAPHIC] [TIFF OMITTED] T4699.182
[GRAPHIC] [TIFF OMITTED] T4699.183
[GRAPHIC] [TIFF OMITTED] T4699.184
[GRAPHIC] [TIFF OMITTED] T4699.185
[GRAPHIC] [TIFF OMITTED] T4699.186
[GRAPHIC] [TIFF OMITTED] T4699.187
[GRAPHIC] [TIFF OMITTED] T4699.188
[GRAPHIC] [TIFF OMITTED] T4699.189
[GRAPHIC] [TIFF OMITTED] T4699.190
[GRAPHIC] [TIFF OMITTED] T4699.191
[GRAPHIC] [TIFF OMITTED] T4699.192
[GRAPHIC] [TIFF OMITTED] T4699.193
[GRAPHIC] [TIFF OMITTED] T4699.194
[GRAPHIC] [TIFF OMITTED] T4699.195
[GRAPHIC] [TIFF OMITTED] T4699.196
[GRAPHIC] [TIFF OMITTED] T4699.197
[GRAPHIC] [TIFF OMITTED] T4699.198
[GRAPHIC] [TIFF OMITTED] T4699.199
[GRAPHIC] [TIFF OMITTED] T4699.200
[GRAPHIC] [TIFF OMITTED] T4699.201
[GRAPHIC] [TIFF OMITTED] T4699.202
[GRAPHIC] [TIFF OMITTED] T4699.203
[GRAPHIC] [TIFF OMITTED] T4699.204
[GRAPHIC] [TIFF OMITTED] T4699.205
[GRAPHIC] [TIFF OMITTED] T4699.206
[GRAPHIC] [TIFF OMITTED] T4699.207
[GRAPHIC] [TIFF OMITTED] T4699.208
[GRAPHIC] [TIFF OMITTED] T4699.209
[GRAPHIC] [TIFF OMITTED] T4699.210
[GRAPHIC] [TIFF OMITTED] T4699.211
[GRAPHIC] [TIFF OMITTED] T4699.212
[GRAPHIC] [TIFF OMITTED] T4699.213
[GRAPHIC] [TIFF OMITTED] T4699.214
[GRAPHIC] [TIFF OMITTED] T4699.215
[GRAPHIC] [TIFF OMITTED] T4699.216
[GRAPHIC] [TIFF OMITTED] T4699.217
[GRAPHIC] [TIFF OMITTED] T4699.218
[GRAPHIC] [TIFF OMITTED] T4699.219
[GRAPHIC] [TIFF OMITTED] T4699.220
[GRAPHIC] [TIFF OMITTED] T4699.221
[GRAPHIC] [TIFF OMITTED] T4699.222
[GRAPHIC] [TIFF OMITTED] T4699.223
[GRAPHIC] [TIFF OMITTED] T4699.224
[GRAPHIC] [TIFF OMITTED] T4699.225
[GRAPHIC] [TIFF OMITTED] T4699.226
[GRAPHIC] [TIFF OMITTED] T4699.227
[GRAPHIC] [TIFF OMITTED] T4699.228
[GRAPHIC] [TIFF OMITTED] T4699.229
[GRAPHIC] [TIFF OMITTED] T4699.230
[GRAPHIC] [TIFF OMITTED] T4699.231
[GRAPHIC] [TIFF OMITTED] T4699.232
[GRAPHIC] [TIFF OMITTED] T4699.233
[GRAPHIC] [TIFF OMITTED] T4699.234
[GRAPHIC] [TIFF OMITTED] T4699.235
[GRAPHIC] [TIFF OMITTED] T4699.236
[GRAPHIC] [TIFF OMITTED] T4699.237
[GRAPHIC] [TIFF OMITTED] T4699.239
[GRAPHIC] [TIFF OMITTED] T4699.240
[GRAPHIC] [TIFF OMITTED] T4699.241
[GRAPHIC] [TIFF OMITTED] T4699.242
[GRAPHIC] [TIFF OMITTED] T4699.243
[GRAPHIC] [TIFF OMITTED] T4699.246
[GRAPHIC] [TIFF OMITTED] T4699.247
[GRAPHIC] [TIFF OMITTED] T4699.248
[GRAPHIC] [TIFF OMITTED] T4699.249
[GRAPHIC] [TIFF OMITTED] T4699.250
[GRAPHIC] [TIFF OMITTED] T4699.251
[GRAPHIC] [TIFF OMITTED] T4699.252
[GRAPHIC] [TIFF OMITTED] T4699.253
[GRAPHIC] [TIFF OMITTED] T4699.254
[GRAPHIC] [TIFF OMITTED] T4699.255
[GRAPHIC] [TIFF OMITTED] T4699.256
[GRAPHIC] [TIFF OMITTED] T4699.257
[GRAPHIC] [TIFF OMITTED] T4699.258
[GRAPHIC] [TIFF OMITTED] T4699.259
[GRAPHIC] [TIFF OMITTED] T4699.260
[GRAPHIC] [TIFF OMITTED] T4699.261
[GRAPHIC] [TIFF OMITTED] T4699.262
[GRAPHIC] [TIFF OMITTED] T4699.263
[GRAPHIC] [TIFF OMITTED] T4699.264
[GRAPHIC] [TIFF OMITTED] T4699.265
[GRAPHIC] [TIFF OMITTED] T4699.266
[GRAPHIC] [TIFF OMITTED] T4699.267
[GRAPHIC] [TIFF OMITTED] T4699.268
[GRAPHIC] [TIFF OMITTED] T4699.269
[GRAPHIC] [TIFF OMITTED] T4699.270
[GRAPHIC] [TIFF OMITTED] T4699.271
[GRAPHIC] [TIFF OMITTED] T4699.272
[GRAPHIC] [TIFF OMITTED] T4699.273
[GRAPHIC] [TIFF OMITTED] T4699.274
[GRAPHIC] [TIFF OMITTED] T4699.275
[GRAPHIC] [TIFF OMITTED] T4699.276
[GRAPHIC] [TIFF OMITTED] T4699.277
[GRAPHIC] [TIFF OMITTED] T4699.278
[GRAPHIC] [TIFF OMITTED] T4699.279
[GRAPHIC] [TIFF OMITTED] T4699.280
[GRAPHIC] [TIFF OMITTED] T4699.281
[GRAPHIC] [TIFF OMITTED] T4699.282
[GRAPHIC] [TIFF OMITTED] T4699.283
[GRAPHIC] [TIFF OMITTED] T4699.284
[GRAPHIC] [TIFF OMITTED] T4699.285
[GRAPHIC] [TIFF OMITTED] T4699.286
[GRAPHIC] [TIFF OMITTED] T4699.287
[GRAPHIC] [TIFF OMITTED] T4699.288
[GRAPHIC] [TIFF OMITTED] T4699.289
[GRAPHIC] [TIFF OMITTED] T4699.290
[GRAPHIC] [TIFF OMITTED] T4699.291
[GRAPHIC] [TIFF OMITTED] T4699.292
[GRAPHIC] [TIFF OMITTED] T4699.293
[GRAPHIC] [TIFF OMITTED] T4699.294
[GRAPHIC] [TIFF OMITTED] T4699.295
[GRAPHIC] [TIFF OMITTED] T4699.296
[GRAPHIC] [TIFF OMITTED] T4699.297
[GRAPHIC] [TIFF OMITTED] T4699.298
[GRAPHIC] [TIFF OMITTED] T4699.299
[GRAPHIC] [TIFF OMITTED] T4699.300
[GRAPHIC] [TIFF OMITTED] T4699.301
[GRAPHIC] [TIFF OMITTED] T4699.302
[GRAPHIC] [TIFF OMITTED] T4699.303
[GRAPHIC] [TIFF OMITTED] T4699.304
[GRAPHIC] [TIFF OMITTED] T4699.305
[GRAPHIC] [TIFF OMITTED] T4699.306
[GRAPHIC] [TIFF OMITTED] T4699.307
[GRAPHIC] [TIFF OMITTED] T4699.308
[GRAPHIC] [TIFF OMITTED] T4699.309
[GRAPHIC] [TIFF OMITTED] T4699.310
[GRAPHIC] [TIFF OMITTED] T4699.311
[GRAPHIC] [TIFF OMITTED] T4699.312
[GRAPHIC] [TIFF OMITTED] T4699.313
[GRAPHIC] [TIFF OMITTED] T4699.314
[GRAPHIC] [TIFF OMITTED] T4699.315
[GRAPHIC] [TIFF OMITTED] T4699.316
[GRAPHIC] [TIFF OMITTED] T4699.317
[GRAPHIC] [TIFF OMITTED] T4699.318
[GRAPHIC] [TIFF OMITTED] T4699.319
[GRAPHIC] [TIFF OMITTED] T4699.320
[GRAPHIC] [TIFF OMITTED] T4699.321
[GRAPHIC] [TIFF OMITTED] T4699.322
[GRAPHIC] [TIFF OMITTED] T4699.323
[GRAPHIC] [TIFF OMITTED] T4699.324
[GRAPHIC] [TIFF OMITTED] T4699.325
[GRAPHIC] [TIFF OMITTED] T4699.326
[GRAPHIC] [TIFF OMITTED] T4699.327
[GRAPHIC] [TIFF OMITTED] T4699.328
[GRAPHIC] [TIFF OMITTED] T4699.329
[GRAPHIC] [TIFF OMITTED] T4699.330
[GRAPHIC] [TIFF OMITTED] T4699.331
[GRAPHIC] [TIFF OMITTED] T4699.332
[GRAPHIC] [TIFF OMITTED] T4699.333
[GRAPHIC] [TIFF OMITTED] T4699.334
[GRAPHIC] [TIFF OMITTED] T4699.335
[GRAPHIC] [TIFF OMITTED] T4699.336
[GRAPHIC] [TIFF OMITTED] T4699.337
[GRAPHIC] [TIFF OMITTED] T4699.338
[GRAPHIC] [TIFF OMITTED] T4699.339
[GRAPHIC] [TIFF OMITTED] T4699.340
[GRAPHIC] [TIFF OMITTED] T4699.341
[GRAPHIC] [TIFF OMITTED] T4699.342
[GRAPHIC] [TIFF OMITTED] T4699.343
[GRAPHIC] [TIFF OMITTED] T4699.344
[GRAPHIC] [TIFF OMITTED] T4699.345
[GRAPHIC] [TIFF OMITTED] T4699.346
[GRAPHIC] [TIFF OMITTED] T4699.347
[GRAPHIC] [TIFF OMITTED] T4699.348
[GRAPHIC] [TIFF OMITTED] T4699.349
[GRAPHIC] [TIFF OMITTED] T4699.350
[GRAPHIC] [TIFF OMITTED] T4699.351
[GRAPHIC] [TIFF OMITTED] T4699.352
[GRAPHIC] [TIFF OMITTED] T4699.353
[GRAPHIC] [TIFF OMITTED] T4699.354
[GRAPHIC] [TIFF OMITTED] T4699.355
[GRAPHIC] [TIFF OMITTED] T4699.356
[GRAPHIC] [TIFF OMITTED] T4699.357
[GRAPHIC] [TIFF OMITTED] T4699.358
[GRAPHIC] [TIFF OMITTED] T4699.359
[GRAPHIC] [TIFF OMITTED] T4699.360
[GRAPHIC] [TIFF OMITTED] T4699.361
[GRAPHIC] [TIFF OMITTED] T4699.362
[GRAPHIC] [TIFF OMITTED] T4699.363
[GRAPHIC] [TIFF OMITTED] T4699.364
[GRAPHIC] [TIFF OMITTED] T4699.365
[GRAPHIC] [TIFF OMITTED] T4699.366
[GRAPHIC] [TIFF OMITTED] T4699.367
[GRAPHIC] [TIFF OMITTED] T4699.368
[GRAPHIC] [TIFF OMITTED] T4699.369
[GRAPHIC] [TIFF OMITTED] T4699.370
[GRAPHIC] [TIFF OMITTED] T4699.371
[GRAPHIC] [TIFF OMITTED] T4699.372
[GRAPHIC] [TIFF OMITTED] T4699.373
[GRAPHIC] [TIFF OMITTED] T4699.374
[GRAPHIC] [TIFF OMITTED] T4699.375
[GRAPHIC] [TIFF OMITTED] T4699.376
[GRAPHIC] [TIFF OMITTED] T4699.377
[GRAPHIC] [TIFF OMITTED] T4699.378
[GRAPHIC] [TIFF OMITTED] T4699.379
[GRAPHIC] [TIFF OMITTED] T4699.380
[GRAPHIC] [TIFF OMITTED] T4699.381
[GRAPHIC] [TIFF OMITTED] T4699.382
[GRAPHIC] [TIFF OMITTED] T4699.383
[GRAPHIC] [TIFF OMITTED] T4699.384
[GRAPHIC] [TIFF OMITTED] T4699.385
[GRAPHIC] [TIFF OMITTED] T4699.386
[GRAPHIC] [TIFF OMITTED] T4699.387
[GRAPHIC] [TIFF OMITTED] T4699.388
[GRAPHIC] [TIFF OMITTED] T4699.389
[GRAPHIC] [TIFF OMITTED] T4699.390
[GRAPHIC] [TIFF OMITTED] T4699.391
[GRAPHIC] [TIFF OMITTED] T4699.392
[GRAPHIC] [TIFF OMITTED] T4699.393
[GRAPHIC] [TIFF OMITTED] T4699.394
[GRAPHIC] [TIFF OMITTED] T4699.395
[GRAPHIC] [TIFF OMITTED] T4699.396
[GRAPHIC] [TIFF OMITTED] T4699.397
[GRAPHIC] [TIFF OMITTED] T4699.398
[GRAPHIC] [TIFF OMITTED] T4699.399
[GRAPHIC] [TIFF OMITTED] T4699.400
[GRAPHIC] [TIFF OMITTED] T4699.401
[GRAPHIC] [TIFF OMITTED] T4699.402
[GRAPHIC] [TIFF OMITTED] T4699.403
[GRAPHIC] [TIFF OMITTED] T4699.404
[GRAPHIC] [TIFF OMITTED] T4699.405
[GRAPHIC] [TIFF OMITTED] T4699.406
[GRAPHIC] [TIFF OMITTED] T4699.407
[GRAPHIC] [TIFF OMITTED] T4699.408
[GRAPHIC] [TIFF OMITTED] T4699.409
[GRAPHIC] [TIFF OMITTED] T4699.410