Public Health Assessment Work Group
Meeting Minutes
November 18, 2002
Attendance:
ORRHES Members attending:
Peggy Adkins, Kowetha Davidson, George Gartseff, David Johnson, James
Lewis, Tony Malinauskas, Pete Malmquist, LC Manley, Herman Cember
Public Members attending:
Gordon Blaylock, Timothy Joseph
ATSDR Staff attending:
Jack Hanley (phone), Bill Murray
Contractors attending:
Gayla Cutler (ERG), Jerome Hershman, M.D., M.S.
(self) via telephone
Agenda
- Minutes from Nov. 4, 2002 meeting
- Presentation by Dr. Jerome M.
Hershman, Associate Chief of Endocrinology and Diabetes, West Los Angeles
VA Medical Center, Director of its Endocrine
Clinic, and Professor of Medicine at UCLA School of Medicine, on thyroid:
- The thyroid's role in the human body.
- Structural and functional abnormalities.
- Detecting abnormalities.
- Treatment of thyroid disease.
- Radiation and thyroid disease.
- PHAWG summary of key points of presentation
(15 minutes)
- F/U recommendation to Dr. Toni Bounds (TN Cancer Registry):
(45 min.)
- Develop a recommendation to ORRHES on the specific cancers by county
that PHAWG would like to calculate cancer rates for, e.g.,incidence,
mortality,etc.
- This list must be based on exposure and biologically plausible outcomes
associated with exposure. (e.g., I-131 released in 1944-1956 from the
X-10 RaLa processing
(see Oak Ridge Dose Reconstruction report).
- Review the handouts from the Epidemiology
Workshop I held during the June 2001
ORRHES meetings. http://www.atsdr.cdc.gov/HAC/oakridge/phact/epid.html
- New
business (20 min.)
- Review action items, next meeting date, time and location
(10 min.)
Purpose: Kowetha Davidson called the meeting to order in the absence
of Bob Craig.
Minutes from November 4, 2002 Meeting
There being no comments regarding the minutes, Pete Malmquist
moved to approve the minutes of the November 4, 2002 meeting.
L.C. Manley
seconded the motion.
The
minutes were unanimously approved.
Thyroid Disorders: Emphasis on Nodular Disease and Cancer
Presenter: Dr. Jerome Hershman, M.D., M.S., Associate Chief of Endocrinology
and Diabetes at the West Los Angeles VA Medical Center, Director of its
Endocrine Clinic, and Professor of Medicine at the University of California,
Los Angeles,
School of Medicine on thyroid.
Summary
Dr. Hershman explained the material contained in the 45 page handout
he provided to those in attendance, which included slides of photos,
graphs,
charts,
and clinical data covering thyroid physiology, thyroid function tests,
hypothyroidism, hyperthyroidism, thyroid nodules, and thyroid cancer.
During
his presentation, Dr. Hershman provided complete answers to the numerous
questions from his audience. Following a lively discussion among
attendees
both in person and via conference call, it was agreed that Dr. Hershman
would change his presentation in the following manner before he presents
it in
person on December 3rd to ORRHES. He will:
- Decrease the amount of
information on Hashimoto’s thyroiditis,
- Provide written information
and/or tables of the symptoms of hypothyroidism and hyperthyroidism,
and
- Offer additional information on radiation induced thyroid cancer,
specifically on the latency period (time between exposure and occurrence/diagnosis
of the cancer).
Kowetha Davidson remarked that the descriptions of hypothyroidism
and hyperthyroidism were especially beneficial in helping to understand
thyroid
cancer.
The questions from the PHAWG members and the answers by Dr. Hershman
are attached in an addendum to these minutes. If further details on the
information presented
are desired, the audio tape of the entire meeting as well as the overheads
used are available at the field office. Also Dr. Hershman will speak at the
ORRHES meeting on December 3, 2002, and that presentation will be recorded
on a videotape that will be available in the Oak Ridge Field Office.
Follow-up
Recommendation to ORRHES:
Presenter: Bill Murray
Summary
Bill Murray explained that Jack Hanley has put together the following
information for the PHAWG to review before the group decides on which
cancers they want
more data from Dr.Toni Bounds of the Tennessee Department of Health’s
Cancer Registry.
Bill Murray began the presentation using an overhead flow chart entitled Health
Outcome Data Evaluation Decision Tree. First, he explained, ATSDR determines
if there is a completed exposure pathway.
The following information is needed to complete the pathway:
- A source of contamination,
- Evidence that the contamination has been
or is being transported away from the source,
- Places where people were,
are, or could be exposed to contaminants from the site,
- A route of
exposure (inhalation, ingestion, or dermal contact) by which people
are, have been, or could be exposed, and
- People that were, are, or
could be exposed to site contaminants?
He went on to explain that a
potential exposure pathway should be considered if evidence is lacking
for one or more of the above elements.
If it is determined that there
was exposure to a contaminant, the next step is to measure the exposure.
He then presented information on the
types of data
needed to measure exposure, ranging from the poorest being “Residence
in a defined geographical area, e.g., county, of a site,” to the best
parameter, “Personal measurement.” He explained the “Measuring
Exposure and Outcomes in Environmental Epidemiology” document. Exposures
occur through contaminants in air, water, food, or soil that comes in contact
with people through swallowing, breathing, or skin contact. Once the contaminant
gets in the body, it can act at that point of entry or can be distributed throughout
the body where it can act upon a target organ or organs.
Finally, he reviewed
the Oak Ridge Dose Reconstruction data, “Summary
of State of Tennessee Exposure Dose and Risk Findings and Possible Carcinogenic
Health Effects for ATSDR’s Initial List of Contaminants of Concern
for Further Evaluation.” The first Contaminant of Concern for Further
Evaluation discussed was iodine-131, which was accepted as a Contaminant
of Concern for
Further Evaluation.
There were some remarks regarding uranium. Though the
Summary of State of Tennessee reported that bone sarcoma cancer has not
been observed in exposed
humans,
Gordon Blaylock commented that it has been observed in animals. Herman
Cember commented that it is a “waste of resources to study uranium
without evidence that is it carcinogenic. Gordon Blaylock responded
that, “Any
radiation will cause cancer if applied in the correct way.” Herman
asked “Have
we ever observed cancer in uranium?” Gordon Blaylock replied “Not
that I know.” Kowetha Davidson noted that, “We are trying to
relate this to the contaminants of concern.”
Peggy Adkins asked, “What
about kidney cancer? We have had doctors find unusual amounts of kidney
cancer.” Bill Murray responded that
kidney cancer has not shown up on the dose reconstruction. James Lewis
commented that
we have decided to work “from the top down” on releases.
Kowetha Davidson commented that “All cancers are not associated
with environmental disease because you have to have a release. There
are causes for pockets
of cancer other than environmental releases. If other releases are found
we can
go back and add those. ATSDR can go back and address these concerns.
Risk findings from the State of Tennessee Dose Reconstruction Reports
regarding White Oak Creek Releases stated that radiological doses and
excess lifetime
cancer risks are not large enough for a commensurate increase in health
effects in the population to be detectable.
The next contaminant Bill
Murray discussed was PCBs. Gordon Blaylock asked if there were zirconium
releases from White Oak Creek. Bill Murray
responded
that he didn’t know. Peggy Adkins asked, “What about cadmium?” Gordon
Blaylock replied “It’s not a radionuclide.” Tony Malinauskas
asked why study only carcinogens and not toxins? Bill Murray responded
because we are compiling a list of the types of cancer that we went more
data on. Gordon
Blaylock stated “The dose reconstruction missed a lot of PCB’s
that came from the lab, and there are no records of what came from White
Oak Creek.
The next Contaminant of Concern for Further Evaluation was
mercury. Kowetha Davidson commented that it can be a very powerful toxin,
even though
it is “not
classifiable as to its carcinogenicity to humans.” Peggy Adkins
asked if testimonial documentation was permissible, or only formal studies.
She stated
there was a completed pathway of neighborhood women - small data, but
100% of a particular population.
Bill Murray reiterated that PHAWG is
looking for types of cancers to recommend to the Subcommittee that we
get more data on. Kowetha Davidson
confirmed
that “We
want to focus on those that are relevant to what we are doing.” Tony
Malinauskas asked if technetium was screened out. Gordon Blaylock and
Bill Murray answered, “yes.”
James Lewis asked what the geographic boundaries are for this purpose.
Kowetha Davison responded “We will be focusing on relevant counties,
eight of them.” Peggy Adkins asked, “Could you explain why
mercury is not carcinogenic?” Bill Murray answered “We are
relying on the International Agency for Research in Cancer (IARC). They
go through their own screening process
to select and classify an element.”
After further discussion, it
was decided that the PHAWG is not yet ready to make recommendations to
the subcommittee. It is therefore tabled for
the present
until a more thorough discussion can be held.
The next PHAWG meeting
is December 2, 2002. The subcommittee meeting is on December 3. Kowetha
Davidson said she will not be here for the
December
2nd
meeting.
Kowetha Davidson summarized this discussion. She said Bill Murray
discussed completed pathways, the five points of a completed pathway,
and the cancers
associated with our contaminants of concern.
Jack Hanley asked if the
PHAWG discussed the findings of the dose reconstruction. Kowetha Davidson
answered that we will have the information, as it is
distributed to the IARC website and their evaluations are highly thought
of.
Peggy Adkins said she would like to re-visit the original list. Jack
Hanley stated that he will go through it with her.
Bill Murray suggested
the PHAWG look over the information distributed at the meeting and check
the IARC website at http://www.iarc.fr to see
their
recommendations.
Jack Hanley asked “What are the main concerns about
this?”
George Gartseff asked “Are we following this one path
to screen out contaminants of concern. Is the groundwater a conduit that
is bringing
something that causes
kidney cancer? “
Jack Hanley asked “What is the concern about
kidney cancer?”
Peggy Adkins: “I brought it up. We know there
have been doctors in Oak Ridge that found several times more kidney cancer
here in Oak
Ridge than in
other places.”
Jack Hanley, “He (Dr. William Reid) presented
his concerns to the Oak Ridge Health Assessment Steering Panel (ORHASP)
in 1992. The State
looked at
Dr. Reid’s concerns.
Peggy Atkins, “I have metals inside my
body, most of them lead to kidney cancer.”
Kowetha Davidson suggested
she go to IARC because if there is data out there it should be in their
evaluation because they are so thorough.
There being no further business,
the meeting was adjourned at 9:10 p.m.
Addendum to Nov. 18th meeting
of the PHAWG
Herman Cember asked Dr.Hershman about the frequency of hypothyroidism
in the general population. He responded that it is very common, found
in 5%
of the
general population and 10% subclinical in the older population.
Page 20
of Dr. Hersershman if the numbers shown were dose dependent. Dr. Hershman
responded that, “Even
with taking size into account we have not done well.” He explained
that the trend is toward using larger doses. The dose in rads varies
from 5-7000
rads twenty years ago to the current 10-20,000 rads, which wipes out
the thyroid but do not damage other tissue.
Page 24, upper slide, of Dr.
Hershman’s handout provided data entitled
Frequency of Thyroid Nodules and Thyroid Ultrasound Surveys. Gordon Blaylock
asked if a lack of nodules “means the thyroid is o.k.” Dr.
Hershman replied, “No.” Gordon also asked whether, because
of the frequency of thyroid nodules, examining for them was part of a
general physical exam.
Dr. Hershman said, “Yes.”
James Lewis asked if the tests
are generally covered by insurance. Dr. Hershman replied that screening
for TSH could possibly be covered, as
the test is
easily justified for people over age 60.
Herman Cember asked if immunosuppressants
are used to treat underactive thyroid. Dr. Hershman responded that large
amounts of Prednisone could,
but that bad
side effects outweigh the benefits.
Jack Hanley asked about sub-clinical
mild symptoms of hypothyroidism often being mis-diagnosed. Dr. Hershman
said if the TSH is mildly elevated
and
the thyroid is normal, most doctors will treat the patient. If the TSH
is only
mildly elevated (5-10%) and the patient has no complaints, there is a
tendency just to observe. If the TSH is over 12 the disease will progress,
he advised.
Page 25, upper and lower slides, are entitled“Thyroid
Incidentalomas-an Epidemic” and “Prevalence of Occult Thyroid
Cancer”:
Herman Cember asked whether the small microcarcinomas progress. Dr. Hershman
replied
that, “Many older people die of other causes with tiny cancers.” Kowetha
Davidson asked if there has been an increase in these cancers that they’re
finding. Dr. Hershman said in his opinion there are no more now than
30 years ago.
Page 30, lower slide, is entitled “Thyroxine Suppression
of TSH to Suppress Size and Growth of Nodules”. Jack Hanley asked
what the doctor uses to shrink the nodule, thyroxine suppression of TSH
or
surgery. Dr. Hershman replied, “If
it takes up radioactive iodine well, then the chances of it being cancer
are small. It can be mixtures of cystic and solid lesions, which would
be cancer.
Pure cystic lesions are generally not cancer.” Herman Cember asked
if a solitary nodule is more likely to become a cancer. Dr. Hershman
replied that
the singular nodules are larger and added that “We worry about
these more than about several nodules.”
Dr. Hershman explained the
upper slide on page 32, that thyroxin was effective in preventing recurrence
of the goiter in 80% of people who
received it
following surgery. Gordon Blaylock asked what risks are associated with
thyroxin. Dr.
Hershman responded that, “If you give too much it can cause osteoporosis.
Keeping the TSH around the lower limit will keep the patient from getting
osteoporosis.”
Page 34, lower slide: Tony Malinauskas asked if thyroid
cancer cells are confined to the thyroid. Dr. Hershman replied, “Initially,
yes. But they can spread into the bloodstream.”
Page 35, upper and
lower slides: Jack Hanley asked about papillary cancer. Dr. Hershman
said it can spread to lymph nodes and/or lungs and was found
in Chernobyl kids. Jack Hanley asked if there was information on papillary
cancer
following Chernobyl. Dr. Hershman said Chernobyl was a very small number.
Tony Malinauskas asked, “Where are those children being treated?” Dr.
Hershman said the treatment “Is not very good there.” Jack
Hanley: “Was
the area an iodine deficient area?” Dr. Hershman: “Yes. It
is still an area of iodine deficiency.” Jack Hanley: “They
picked up more of this radioactive iodine because of their iodine deficiency?” Dr.
Hershman: “Yes.”
Kowetha Davidson asked, “How long
has iodine been used in salt?” Dr.
Hershman replied, “Since the 1920’s.” Kowetha: “In
the 1950’s no iodine deficiency in the U.S.?” Dr. Hershman, “Yes.” James
Lewis: “Forty to fifty years ago, what would have been the iodine
intake?” Dr.
Hershman replied that 25-30% of the kids in the Midwest had goiter. You
found iodine deficient kids in the mountainous regions, but around the
ocean kids
get plenty. There was a program throughout the world to eradicate iodine
deficiency and provide iodized salt. In Chernobyl there is a 20% incidence
of adolescent
thyroid.” James Lewis asked if kids were deficient in iodine in
Chernobyl and how their diets compare with those of U.S. children. Dr.
Hershman replied
that the diets of U.S. children contain 150-200 micrograms of iodine
per day, that 150 is considered deficient, 50-100 is borderline, and
less than 50 is
probably what the kids at Chernobyl had. In response to a question from
Tony Malinauskas about iodine from table salt, Dr. Hershman responded
that iodine
is ingested from milk too, and fortified bread. Although iodine intake
has fallen 50% in the last 20 years, “Ours is considered good.”
Page
37, upper and lower slides: Herman Cember asked if people exposed to
fallout should be screened for thyroid cancer. Dr. Hershman replied, “Yes.
If a nodule is found, biopsy it. Nodules in young people, adolescents,
is particularly
suspicious.”
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