Public Health Assessment Work Group
Meeting Minutes
February 10, 2003
Attendance
ORRHES Members attending:
Bob Craig (Work Group Chair), Kowetha Davidson (Subgroup Chair),
W. Don Box, George Gartseff, David Johnson, James Lewis, Tony Malinauskas,
and LC Manley
Public Members attending:
Gordon Blaylock and Bob Peelle
ATSDR Staff attending:
Jack Hanley, Bill Murray, and Lorine Spencer
ERG Contractor:
Michelle Arobogast (phone) and Liz Munsen (phone)
Purpose
Bob Craig called the PHAWG meeting to order and attendance was noted
for the record.
The purpose of the meeting was to (1) discuss the minutes from the February
3, 2003, PHAWG meeting, (2) review and discuss comments received and
compiled by Tony Malinauskas on the Y-12 Uranium Releases Public Health
Assessment (PHA), and (3) develop a recommendation to the ORRHES on the
comments.
Minutes from the February 3, 2003, Meeting
Bob Craig asked the PHAWG
for comments on the minutes. Gordon Blaylock noted one correction on
page six where the text states, … “it
could be over 100 millirem (mrem).” Mr. Blaylock actually said “100
rem.” There was a motion to approve the minutes as corrected and
the motion was seconded. The February 3, 2003, minutes were unanimously
approved.
Review and Discussion of the Comments on Y-12 Uranium Releases
PHA Compiled by Tony Malinauskas
Facilitator: Bob Craig, ORRHES
Bob Craig asked the PHAWG for suggestions on how to approach this discussion.
Kowetha Davidson believed that they should go through all of the comments
and decide how each one should be handled. Some comments may not need
to be brought up, but others may require a thorough discussion. She added
that some items may need to be corrected and/or clarified and that this
should be done during the meeting. Dr. Davidson explained that some of
the comments are editorial. For these types of comments, the PHAWG needs
to ensure that the comment is correct. However, if a comment effects
the interpretation of the data, she does not consider this to be an editorial
comment.
Tony Malinauskas stated that he did not try to edit any of the comments.
Bob Craig reminded the PHAWG that these comments would be submitted
by the PHAWG for consideration by ATSDR. Since the PHA is ATSDR’s
document, the agency has the final decision to accept the comments. Dr.
Craig asked Jack Hanley if he was correct on this point and Mr. Hanley
stated that Dr. Craig was accurate. Although these are recommendations,
ATSDR will provide an answer for all of the comments, excluding those
that are editorial.
Bob Craig stated that he does not think that the PHAWG is concerned
with how information is stated; this is ATSDR’s responsibility.
However, Dr. Craig noted that if ATSDR states something differently than
how the PHAWG suggested, then ATSDR should provide an explanation for
why it was stated differently. Kowetha Davidson was concerned with ensuring
that the comments were accurate and did not contain any errors. Bob Peelle
agreed that the PHAWG did not want to send items to the ORRHES that they
know are incorrect.
Editorial Comments
Tony Malinauskas expressed that he would side with the reviewers. He
stated that if the reviewers were incorrect, then the document is worded
in a way that generates this misconception. Bob Peelle added that it
could be a “point of picking up the wording.” Kowetha Davidson
said that this could be correct, but that these comments no longer belong
to the individual reviewer; once these comments were compiled, they became
the PHAWG’s comments. James Lewis asked for an example. Dr. Davidson
read the following editorial comment that referred to page 1, line 30,
in the PHA: “The word “species” should replace “chemicals” as
radionuclides are not chemicals. Metallic uranium or uranium oxide is
a chemical, but U-235 is a radionuclide, not a chemical.” Dr. Davidson
asked the PHAWG if this comment was correct, and many members of the
PHAWG responded that it was accurate. Dr. Davidson then asked about the
chemical effects of uranium and if uranium is a radionuclide. Dr. Malinauskas
responded that metallic uranium is a chemical, but that U-235 is a radionuclide
and not a chemical. Dr. Peelle added that regular uranium is also radioactive.
Kowetha
Davidson asked about the editorial comment that refers to page 4, line
16, of the PHA because she was having difficulty interpreting
the statement. Bob Peelle stated that this was his comment and that
he agrees it is not exactly editorial. However, Dr. Peelle explained
that
his comment was editorial in that he was requesting that footnotes
be included when data are taken and used in the text for a specific purpose
(e.g., a table). Tony Malinauskas added that if a comment asked for
an
explanation, he listed those comments as editorial.
Kowetha Davidson requested a point of clarification on the comment referring
to page 4, line 21, of the document that reads: “This line should
read ‘concentration of U-234 and U-235 in Scarboro. Consequently,
airborne doses due to U-234 and U-235 based on this.” She stated
that neither the document nor the proposed change was accurate, and that
this needed to be corrected. Dr. Davidson explained that levels of airborne
contaminants have concentrations, not doses; a dose is what enters the
body. Bob Craig stated that he thought the reviewer was referring to “dose
due to an airborne concentration.” Dr. Davidson suggested that
the line should read “airborne concentrations are based on.”
Kowetha Davidson noted the use of “margins of safety” in
several comments. She was not sure what the person meant and thought
it may refer to “margin of exposure.” Bob Craig asked Dr.
Davidson to point out where this term was used. She stated that the term
was used in many places, but she noted that comments referring to page
5, lines 10, 21, and 24 are a few that use this verbiage. Dr. Craig said
that there are margins of safety in ATSDR’s minimal risk level
(MRL). Bob Peelle agreed with Dr. Craig that the “margin of safety” usage
probably refers to the MRL. Dr. Davidson explained that there is a difference
between an actual environmental exposure and a reference point, which
is the margin of exposure. She said that when the word “safety” is
used, it implies that something is “safe.” Dr. Peelle noted
Dr. Davidson’s point that the “margin of safety” may
be given a technical meaning instead of a descriptive one. Dr. Craig
said that this is routinely used in this manner when referring to “margin
of safety” and added that he has heard Jack Hanley use this term
as well.
Jack Hanley responded to Bob Craig’s comment. Mr. Hanley explained
that when you develop a reference dose for an MRL, there are different
words used for it, which are sometimes called “safety factors.” His
interpretation is that “margin of safety” in these comments
refers to the screening and reconstruction exposure doses that were used
to estimate exposures. He continued that these entailed some conservative
assumptions, which led to an overestimation of the exposure. Mr. Hanley
added that this overestimation is appropriate when conducting a screening
assessment. ATSDR compared the conservative estimated exposure doses
to some of the screening values, which are also conservative. He thinks
that the reviewer would like ATSDR to go into further detail on this
aspect of the PHA.
Kowetha Davidson referred to the following comment concerning page 13,
line 12: “This report should not prolong the myth that Scarboro
was located next to Y-12 to place Afro-Americans at risk. What is now
Scarboro was established in 1943 as a white trailer camp (Gamble Valley
Trailer Camp); it was converted about 1950 to segregated Afro-American
residential housing using the street and utilities as the report states.” Dr.
Davidson did not see this as a comment and thought that ATSDR had described
the Scarboro community today. Bob Craig asked if this statement should
be lined out. Bob Peelle thought that the comment should not be deleted
because some people feel very strongly about this issue. Dr. Davidson
asked if there was anything that they could do about this concern. Dr.
Peelle said that the statement suggests that the PHA should not “prolong
the myth,” and if it does, then the report should be re-worded.
James Lewis noted that there is a lot of emphasis on Scarboro and that
he had thought that Gamble Valley was the geographical area in question.
He stated that Scarboro is only a portion of this area and that there
should be more emphasis on the geographical area, not just on Scarboro.
LC Manley explained that most of the data were taken from Scarboro and
as a result, Scarboro was used as a baseline. Mr. Lewis said that he
is not disagreeing with that, but that Scarboro is only one segment of
the area. Mr. Manley stated that if Scarboro is used as a baseline, then
the emphasis should be on that area. Bob Craig asked if Gamble Valley
was the populated area and if the majority of the receptors were located
there. Bob Peelle replied that this area would have been the most populated
during the time that major exposures occurred. Mr. Manley said that many
people were concerned because data were collected from Scarboro, but
data from throughout the city were not utilized. He added that Scarboro
is only a small segment of the city of Oak Ridge.
Bob Craig agreed with LC Manley’s comments. Dr. Craig said that
he assumed that Scarboro data were used because this was the closet population
to the potential source. He added that you would presume that the highest
levels of exposures would be found in Scarboro. Mr. Manley said that
data from the rest of Oak Ridge is needed to draw a comparison. Dr. Craig
noted that he did not think that there were uranium data from the rest
of the city. Kowetha Davidson thought that Jack Hanley had mentioned
that there were source-sampling data. James Lewis noted that the emphasis
is on looking at an affected area near Y-12. He said that it is acceptable
to accept data taken from Scarboro, but that he thought the objective
was to explain the area that surrounds Scarboro. Mr. Manley stated that
another place was not investigated.
Kowetha Davidson pointed out that much of the sampling was conducted
in Scarboro because of the residents’ interest. She said that this
is why there is more sampling from Scarboro than other parts of the city.
Dr. Davidson thought that there were air monitoring stations at other
places and that Scarboro was used as a reference point; if concentrations
were low in Scarboro, then they were low everywhere else. Dr. Davidson
explained that this rationale made various assumptions, including wind
patterns and how particles are transmitted in air. She stated that these
assumptions cannot be made because Scarboro is not really a reference
point, but another place that was sampled. Tony Malinauskas said that
unless someone can make an argument and provide the line of reasoning
why Scarboro would be most affected, then airflow patterns and other
aspects would have to be considered.
Jack Hanley clarified that during his presentation with Paul Charp in
December, they said that ATSDR would be using the Dose Reconstruction
Study to evaluate historical releases. The study used the Scarboro community
as a reference location and this was why the emphasis was on Scarboro.
ATSDR looked for environmental data in the area and found uranium sampling
conducted by Florida A&M and the U.S. Environmental Protection Agency
(EPA) in Scarboro. In December, one of the meeting participants suggested
that ATSDR look further to identify additional areas so that Scarboro
could be compared to other areas in Oak Ridge. ATSDR searched for information
and found some data, but it could not be incorporated into the document
by the time that the PHA was released. In January, Mr. Hanley and Dr.
Charp presented these additional data to the PHAWG, and these will be
added into the document. The additional data will include other locations
for biota vegetable samples, an additional air monitor near Illinois
Avenue (close to the museum), other perimeter air monitoring locations,
and additional information as well. Mr. Hanley stated that ATSDR attempted
to locate other data, which included looking at Comprehensive Environmental
Response, Compensation, and Liability Act (CERCLA) sites in the area.
However, the samples could not be used. ATSDR also worked with the U.S.
Department of Energy (DOE), examined data from the Tennessee Department
of Environmental Conservation (TDEC), and is trying to use available
data for the broader Oak Ridge area. Bill Murray asked if these data
would be in the next draft. Mr. Hanley replied that all of the figures
that he and Dr. Charp presented will be added, and any other data that
become available will also be incorporated.
Kowetha Davidson stated that the comment regarding page 33, “Was
iodine and tritium released as a gas or a particle in gaseous form?” should
be moved into the community concerns database as it does not relate to
uranium. Tony Malinauskas added that there is a lot of information in
the report that does not relate to uranium or Y-12 that should be omitted,
unless it provides a historical background.
Kowetha Davidson referred to a comment regarding page 35, line 26. The
comment suggests that the PHAWG should, “delete ‘on the ORR’ and
replace it with ‘to residents in the Scarboro community due to
uranium release from Y-12.’” Dr. Davidson felt that this
required a discussion. Bob Craig thought that even though the residents
of the Scarboro community may be the primary concern in the PHA, the
document is still concerned with the public health effects from the releases
from Y-12. Dr. Craig voted to leave the title of the document as the
Uranium Assessment from Y-12, as opposed to the Exposures to Scarboro
Residents from Y-12.
Bob Craig brought up a typographical error in the comment for page 35,
line 16. He asked if the reviewer meant “word” frequency
and not “work” frequency. Kowetha Davidson said that it was
her error and that it should read “word.”
Tony Malinauskas was confused about the usage of the term “ORR.” He
said that in some cases, ORR clearly refers to the DOE property. However,
in other cases, the term refers to a property much greater than the DOE
property. Dr. Malinauskas suggested that the term ORR be defined more
clearly. Jack Hanley responded that he noted this comment and that Dr.
Malinauskas made a good point.
Kowetha Davidson stated that she wrote the comment for page 26, Table
2, concerning using a different acronym for “RBC.” She explained
that as a toxicologist, she uses this acronym to define red blood cells.
Kowetha Davidson pointed out another editorial comment. She read the
following comment, which refers to page 62, lines 18 through 20: “The
term ‘activity’ is erroneously used for ‘isotopic composition.’” Dr.
Davidson thought that the term “erroneous” should be replaced
with “mistakenly” because she believes that the word connotes
an adversarial relationship.
Tony Malinauskas stated that Tim Joseph’s comments had not been
incorporated. Bob Craig asked if they could be integrated or put as an
addendum. Dr. Malinauskas stated that he could add Dr. Joseph’s
comments into the document and Dr. Craig said that was the best solution.
Kowetha Davidson noticed that the report sometimes provides results
from studies, but sometimes it does not. She suggested that a general
statement or “two-liner” of the outcome be included for each
study.
Technical Comments
Bob Craig asked if there were any comments regarding the first paragraph.
Bob Peelle responded that the comment did not need to be changed.
Kowetha Davidson reminded the group that all of these comments needed
to reflect the PHAWG. Tony Malinauskas stated that he had only copied
and pasted the comments, thus when comments refer to “I,” it
does not mean him. Bob Peelle asked if this meant that individual comments
would not be forwarded to ATSDR. Bob Craig replied that this was correct.
Dr. Craig added that individuals will have an opportunity to comment
on the PHA, but the comments that the group is reviewing will become
the comments of the PHAWG. Dr. Craig explained that the PHAWG is part
of the production of the document and that a draft for public comment
will be released at a later date. Dr. Peelle asked if the individual
comments could be transmitted to ATSDR in case they add value. Dr. Davidson
replied that unless they are going to change the entire process and turn
this PHA into a public comment draft, then it should not be done in that
manner.
Gordon Blaylock stated that he does not see the purpose of deleting
many of the comments. Kowetha Davidson replied that the PHAWG has to
ensure that they want the comments included. She added that these comments
are no longer from each individual; these comments are from the PHAWG
to the ORRHES. Dr. Davidson explained that there has to be consensus
on the comments before they go to the ORRHES, or ORRHES will not assess
the comments. Mr. Blaylock asked why they had people submit individual
comments, instead of working everything out as a group. Bob Craig replied
that they want the best input possible. Dr. Davidson said that the PHAWG
should look at these comments to see if they are in agreement. If the
PHAWG approves the comments, then they become the PHAWG’s comments
and will be submitted.
Gordon Blaylock expressed concern because the workgroup changes from
week to week. Bill Murray clarified Mr. Blaylock’s point by saying
that the only people who received copies of the PHA for comment were
the agencies involved and people who have been members of the PHAWG.
Bob Craig added that it should be noted that no comments have been removed
thus far, and that he does not anticipate that the group will delete
many.
James Lewis brought up a concern. He stated that people may not be aware
of how the comments are being combined by the PHAWG, and people may think
that their comments were lost if they were not included. Mr. Lewis stated
that the PHAWG needed to be upfront about their policy to avoid future
problems and upsetting the public. Bill Murray stated that Mr. Lewis
is making a good point. He suggested that when the PHAWG compiles the
comments that they are going to submit to the ORRHES, a letter should
be sent to all of the PHAWG members, which states that their comments
may or may not be included in the compiled document. The letter could
also explain that if a person’s comments were not included, there
will be an opportunity to submit the comments at a later date. Mr. Murray
asked Jack Hanley if this was a sound plan. Mr. Hanley said that if someone’s
comments were not accepted, it would be advisable that the PHAWG inform
the individual.
Jack Hanley noted that there may have been some confusion with the PHA
draft release. He stated that some PHAWG members did not receive a cover
letter with their draft because they received it directly from the ATSDR
office. Normally, ATSDR sends what is called an “initial release,” which
is what was provided to the PHAWG. The “initial release” is
usually evaluated by the agencies that are involved, and is referred
to as a “data validation” period. Since there is so much
interest at Oak Ridge with the ORRHES and the work groups involved, the
subcommittee has been given the opportunity to provide input at this
point, while ATSDR is also having data validation with other agencies.
The ORRHES has delegated this task to the PHAWG. Once comments are given
to ATSDR from the ORRHES, the agency will respond to the subcommittee.
Based on comments from the ORRHES and other agencies, ATSDR will release
a public comment draft, which enables individuals to submit their comments.
Bob Craig asked if everyone approved of how the comments flowed. Kowetha
Davidson responded that the fourth paragraph, which refers to sick children,
should be moved to the community concerns database. Bob Peelle agreed
that this did not belong in the comments. Dr. Craig suggested that this
comment be removed. James Lewis said that he did not disagree with Dr.
Davidson about putting this information into the concerns database. However,
he wanted to be assured that this issue was addressed. He suggested reviewing
the minutes from the meeting that was held in Scarboro, and conducting
a follow-up to assess how the doctors were monitored and to ensure that
every child was under a physician’s care. Dr. Craig stated that
this could be the point in this comment. He ascertained that the reviewer
may have been searching for a one-sentence conclusion to say … “and
these children were followed up on by … after such and such a time
and are under doctor’s care.” Dr. Davidson asked if this
was in the summary of the documents presented in the report because it
would mean that there were references for all of the details from previous
studies that the report summarized.
Bob Craig stated that paragraph four would be removed from the comments
and moved into the concerns database, unless someone disagreed. LC Manley
expressed concern because this was the impetus for the investigation
in Scarboro and thus, he believes there should be a follow-up. Dr. Craig
said that Mr. Manley had a good comment and that the PHAWG should suggest
that ATSDR include the follow-up in the PHA that was conducted. He asked
if James Lewis could obtain the references and then the PHAWG would write
the information and provide it to ATSDR. The PHAWG members decided to
remove this paragraph from the comments and enter it into the community
concerns database. After the comment is in the database, ATSDR will provide
a response. Jack Hanley looked at page 31 and concluded that Mr. Manley
had a good point; Mr. Hanley said he would address the issue. He added
that the report does not provide the final results or describe what happened
to the children who were evaluated. ATSDR will attempt to clarify this
issue.
Kowetha Davidson asked about the third paragraph on the first page of
the comments. Bob Craig stated that he thinks it is a valid comment.
Bob Peelle said that there may be some places in the report where the
total is discussed, but that the reader does not know if it is background.
Tony Malinauskas added that in some cases, the normal background is used
as a reference point; it sounds as though this dose is not very high
because normal background is 360 mrem/year. Dr. Malinauskas’ opinion
was that the impression is given that the actual dose was what was calculated,
as opposed to what was calculated plus background.
Bob Peelle pointed to the fifth comment that referred to Scarboro receiving “negative
publicity.” Dr. Peelle stated that ATSDR needed to be “mindful” of
this in the report. Kowetha Davidson interjected that the report gave
her the impression that Scarboro was not contaminated. James Lewis asked
what the commenter meant by “negative publicity.” Dr. Davidson
referred to the part of the comment that stated, … “claiming
that Scarboro is contaminated.” She said that the “claiming” is
the negative publicity. Bob Craig added that publicity has affected people
as it has probably caused residents to worry about their health, about
living in Scarboro, and with regards to economics. Dr. Craig noted that
the Scarboro residents recognize that results from studies do not show
elevated levels of uranium, but the perception that Scarboro is contaminated
has had an impact.
A meeting participant commented that this would constitute an “adverse
impact.” Bob Craig agreed that Scarboro had suffered an adverse
impact because of the perception that Scarboro is contaminated. Kowetha
Davidson stated that the conclusion of the PHA does not indicate this.
Tony Malinauskas noted that this information is mentioned in the summary
on page 3 of the document, but that the reviewer is requesting a stronger
statement. Dr. Craig concluded that the reviewer wanted a stronger statement
to show that Scarboro was not contaminated, but the commenter also wanted
to identify that, “Scarboro has been impacted by the perception
that there is contamination, when in fact there is not.” Dr. Davidson
reminded the PHAWG that ATSDR could not write a statement without having
reference material to support it. She added that she did not believe
that sociological, psychological, and economic studies had been conducted
in Scarboro, and without these types of data, the report could not include
what the reviewer suggested. James Lewis thought that the economic impact
on Scarboro had been assessed. Dr. Craig commented that the reviewer
may have used the correct word, when stating that, “ATSDR should
be mindful of the psychological, sociological, and economic consequences.” Dr.
Craig suggested that the PHAWG retain the word “mindful” in
this reviewer’s comment, and have ATSDR attempt to find information
to document this claim. George Gartseff said that the reviewer was looking
for a citation and that ATSDR should “be more forthcoming in saying
that there really is no problem here.” Dr. Craig concluded that
the PHAWG should keep the comment as it is, and only change the term “negative
publicity” to “adverse publicity.”
Bob Craig referred the PHAWG to paragraph seven that addressed summary
and conclusions. Kowetha Davidson read section “a” to the
group, “Brief quantitative comparisons of the Scarboro levels to
the screening levels used.” Dr. Davidson asked if the reviewer
was referring to ATSDR’s MRL, and if so, then “MRL” should
be placed in parentheses. Bill Murray replied that if Dr. Davidson understood
this to mean the MRL, then she should add it. Dr. Davidson said that
they needed to be sure that they are interpreting the screening value
correctly. Bob Peelle stated that this probably refers to the MRL. Tony
Malinauskas recommended that the term “screening value” also
be added into the document’s glossary. Dr. Davidson asked Dr. Malinauskas
if the document uses the term “screening value,” but he could
not remember. Dr. Davidson agreed that if the term is used in the document,
then it should be added to the glossary. Dr. Craig asked for clarification
on the items that Dr. Davidson was referring to. She stated that she
was discussing the first two subsections under paragraph seven, where
one item refers to “screening level” and the second item
refers to “screening value.” Dr. Craig suggested that both
be changed to “levels.”
James Lewis asked about page 82 in the report. He read a comment that
was taken from the concerns database, “It is generally believed
by most people who live in Tennessee and perhaps the nation that the
Scarboro neighborhood in Oak Ridge, Tennessee, is contaminated with mercury...
The data showed very high levels of mercury contamination in several
areas of Oak Ridge, however, the media primarily focused attention on
mercury contamination in the Scarboro neighborhood (where no significant
mercury was ever found).” Mr. Lewis stated that this issue needs
a response. Tony Malinauskas clarified that this concern deals with mercury,
and that it would not be answered within this document because this is
the uranium PHA.
Bob Peelle discussed the first paragraph on page two that begins with, “I
do not agree.” Dr. Peelle stated that the beginning of this sentence
needed to be changed to “some do not agree.” Kowetha Davidson
stated that other wording in the comments needed to be changed also to
reflect the PHAWG, instead of an individual. Dr. Peelle added that the
last two sentences of the paragraph are very important. He stated that
if there are two different approaches and ATSDR chooses one, then ATSDR
should acknowledge the difference. Bob Craig agreed with Dr. Peelle and
said that they need to phrase the comment by “saying that there
is disagreement regarding the methodology of using an MRL.” Dr.
Davidson commented that there are two good points within this paragraph.
One idea pertains to the MRL, and the other idea refers to the use of
the whole body dose. She asked if there are some situations where ATSDR
uses the MRL, and other situations that it is not used. Gordon Blaylock
responded that MRLs could be used to evaluate somatic effects of radiation,
but not for carcinogenic effects.
Bob Craig asked if everyone agreed with the re-wording of the first
paragraph on page two. Bob Peelle referred to the second line, which
states that … “it seems quite indirect.” Dr. Peelle
noted that this phrase does not apply to everyone and that it needs to
be more general. Dr. Craig responded that this would result in a statement
from ATSDR that there are people who do not agree with using the MRL
or the whole body dose. Dr. Peelle responded that this needed to “say
why” because there is no rationale provided.
Bob Craig examined the next paragraph that referred to Appendix C. He
summarized that the reviewer thought that this appendix was confusing
and that it needed to be made more understandable. Dr. Craig asked the
PHAWG if everyone agreed with this comment. Kowetha Davidson stated that
the comment reminded her that there needs to be more division in the
table of contents. Bob Peelle replied that the appendix is confusing
because it is unclear what method was used and the data that were applied.
Dr. Craig read the following re-wording, “There should be a clearer
explanation of the method used and which data were selected.” He
stated that the remainder of the paragraph would be removed. Bill Murray
asked if Dr. Craig wanted to retain the part of the comment that referred
to the Task 6 report. Dr. Craig and Dr. Peelle both stated that the Task
6 part should be eliminated.
Bob Craig informed the PHAWG that a lengthy discussion was needed for
the next comment, which referred to the “ATSDR MRL of 5,000 mrem
effective dose equivalent.” Dr. Craig explained that he wanted
to keep most of the words intact and say, “there is a disagreement
regarding the proposed MRL of 5,000 mrem effective whole body dose.” Kowetha
Davidson noted that the statement should read “5,000 mrem average
over 70 years.” Gordon Blaylock replied that the effective whole
body dose could occur anytime over the 70 years. Dr. Davidson said that
this translates to 71 mrem/year, and that maybe ATSDR should base its
MRL on the mrem/year rather than the average over 70 years. She added
that ATSDR continues to go back and forth, which results in different
interpretations of the same data. Dr. Davidson said that this translates
to 5,000 mrem over 70 years, but then this is taken back to what could
be 5,000 mrem in one year. Dr. Craig replied that ATSDR does this as
the screening level for radiation is 71 mrem/year. Tony Malinauskas asked
if that was correct, or if it is 5,000 mrem over 70 years. Dr. Craig
said that it was derived by dividing 70 (years) into 5,000. Dr. Davidson
said that they would still be coming back to 5,000 mrem, which could
be a one-year exposure. Dr. Craig responded that if in one year, someone
was exposed to more than 71 mrem, then that population would “pop” out
of the screening and a more in-depth analysis would be conducted. Dr.
Craig asked Bill Murray if he was correct. Mr. Murray responded that
it was “not ATSDR’s time to respond” because it was
the agency’s time to receive comments.
Kowetha Davidson explained that she is not familiar with the technicalities.
However, she knows that there is confusion associated when the 71 mrem/year
level is extrapolated to total mrem over 70 years. She suggested that
ATSDR use only one of the terms and not even reference the other one.
Gordon Blaylock said that they should both be left in the text. He added
that they should look into it further and discuss it as a group. Dr.
Davidson asked how you can factor in that the 5,000 mrem is averaged
over 70 years because it is not mentioned in these comments. Mr. Blaylock
asked if she was referring to the effective whole body dose. Bill Murray
said that it is the effective dose equivalent. Bob Craig explained that
this is not what ATSDR’s screening level is; its screening level
is over 70 years.
Don Box referred to his comment from the February 3, 2003, PHAWG meeting.
He had suggested that the first paragraph of Appendix F be moved to the
front of the document. He said that this could alleviate much of the
confusion on the topic. Bob Peelle said that he basically agrees with
these paragraphs. However, he mentioned that there is a problem that
Kowetha Davidson had highlighted previously. Dr. Peelle explained that
there is a lot of disagreement surrounding these levels, and that ATSDR
should recognize the disagreement in the report. Bill Murray suggested
that ATSDR take the appendix and place it into the body of the report
because it could clarify these issues. Bob Craig asked Mr. Box if he
made this suggestion in the comments. Mr. Box replied that he had made
the comment to Jack Hanley last week. Dr. Craig said that Mr. Box should
write down the suggestion so it could be included in the comments. Dr.
Craig concluded that the paragraphs that they were discussing were well
written. However, the comments do not reflect the opinion of the PHAWG,
and opinions differ on the use of the cumulative effective whole body
dose.
Gordon Blaylock suggested that ATSDR look at the paragraphs and make
a decision on further action. Bob Craig responded that these comments
are going to be comments from the PHAWG to the ORRHES. Bill Murray stated
that the PHAWG could make a comment that ATSDR would be sensitive to
and the agency would take action to clarify the situation. Kowetha Davidson
said that the comment to ATSDR should be to “clarify the issue
of the 5,000 mrem average cumulative effective dose.” Dr. Craig
concluded that ATSDR should clarify the use of the 5,000 mrem “lifetime.” Mr.
Blaylock stated that ATSDR is using the effective whole body dose, which
is one of the problems. He said that this needed to be straightened out
before the report is released. Dr. Craig explained that these comments
are from a “very distinguished scientist,” and that these
remarks should be made as the scientist’s own comments. He said
that these comments should be included in the public comment period that
will occur later.
Gordon Blaylock asked about the MRL being used to look at carcinogenic
effects. Bob Craig asked Mr. Blaylock if he was referring to one of the
comments. Mr. Blaylock said he was referring to the definition of an
MRL in Appendix F. Kowetha Davidson suggested that the PHAWG ask to have
the MRL clarified. Mr. Blaylock commented that ATSDR says that an MRL
should not be used for carcinogenic effects from radiation, but it is
listed as such in the document. Dr. Craig said that ATSDR is inconsistent
with its own approach. Bob Peelle suggested that ATSDR clarify the use
of the MRL in carcinogenic equations.
Bob Peelle explained that there is concern among some members of the
public. He stated that people are worried that ATSDR is making a mistake
in their methodology and that the PHAWG does not want a mistake to be
made. He added that he is aware that it would be difficult for ATSDR
to change its approach, but that he thought the agency should consider
it to avoid errors. Dr. Peelle added that he wants to make sure that
ATSDR’s message “gets through” to the public. Bill
Murray asked Dr. Peelle to write-up his opinion and submit them to Tony
Malinauskas.
Bob Craig suggested that the PHAWG have the following three comments
to replace the reviewer’s paragraphs: 1) clarify the use of the
5,000 mrem lifetime, 2) clarify the use of the whole body dose, and 3)
attach the full text on the MRL as a rationale.
Jack Hanley asked if someone had mentioned that ATSDR used an MRL to
evaluate cancer effects. Gordon Blaylock stated that he had made this
comment because the MRL is used in this manner in Appendix F. Mr. Hanley
referred the PHAWG to pages 72 and 73 of the PHA, where the document
details evaluating past releases within the health implications section.
Mr. Hanley explained that this section discusses what ATSDR considers
to be the dose comparison value. He referred the group to the bottom
of page 72 and stated that, “we are evaluating the carcinogenic
effects of past radiation exposure to the 5,000 mrem over 70 years.” Mr.
Hanley added that ATSDR uses the 5,000 as the comparison value to evaluate
the carcinogenic impact that may result from exposure. He then referred
the PHAWG to the top of page 73 and said that the 84.5 mrem over 70 years
was compared to the MRL to evaluate noncancer effects. Mr. Hanley emphasized
that the MRL is ONLY used to identify noncancer health effects. He wanted
to clarify that ATSDR was very careful in its use of the MRL and the
5,000 mrem, and added that ATSDR looked at cancer causing effects from
radiation, as well as noncancer effects.
Bob Peelle asked Jack Hanley about page 247 in Appendix F. Mr. Hanley
responded that this concerned the committed effective dose of 5,000 mrem
over 70 years, which is not an MRL. Bob Craig asked if this was a screening
level. Mr. Hanley replied that this was a screening level that ATSDR
developed. Tony Malinauskas said that Mr. Hanley had just compared a
screening level with an MRL. He continued that the PHAWG had previously
decided that a screening level should indicate an MRL and now they are
saying that this is not correct. He said that there were two screening
levels for radiation – the 5,000 mrem to evaluate cancer impact
and the MRL to evaluate noncancer radiation. Dr. Peelle stated that there
are two problems. First, the PHAWG misread items in the PHA. And second,
it is possible that the objection is to the use of the 5,000 mrem as
a limit. He said that ATSDR does not have to call this limit an MRL;
instead, it could be called a “comparison level.”
Gordon
Blaylock asked Jack Hanley if the MRL for radiation effects was based
on organ dose, and not on the committed effective dose equivalent.
Mr. Hanley responded that because he is not a health physicist, this
question is outside the realm of his expertise. However, Mr. Hanley
suggested that Paul Charp explain this to the PHAWG. Mr. Blaylock replied
that
further explanation by Dr. Charp would be helpful because an MRL should
not be based on the committed effective dose equivalent. Bill Murray
stated that the MRL is based on background. He explained that you have
a certain amount of mrem/year, you take 360 and divide it with an uncertainty
factor of 3, which equals 120 and is rounded off to 100. Mr. Murray
said that the MRL is not based on a cumulative effective dose. Mr. Hanley
added that no studies were found that showed noncancer effects from
chronic,
long-term exposure to radiation. He stated that the only noncancer
effects seen were drops in intelligence quotient (I.Q.) from exposure
to acute
levels. Bill Murray stated that even though this is not a carcinogen,
if you looked at carcinogenic effects, there would not be any risk
at that background and you would not find any studies that showed an
increased
risk at that level. Mr. Hanley stated that he could formulate a risk
number to show the theoretical risk at background levels. However,
to his understanding, there are no studies in existence that show adverse
health effects observed at background levels.
Gordon Blaylock asked if there have been any effects from radon at background
levels. Bill Murray replied that he thinks there have been effects from
radon daughters. He knows that there have been effects seen in occupational
studies, but he is not familiar enough with the literature to provide
exact information. Jack Hanley stated that he does not think that there
are noncancer health effects from radium, which is what the MRL is based
on. Mr. Murray added that it is radon and a couple of the radon daughter
products that can cause effects because they remain in the lungs.
Bob Craig requested that the PHAWG return to the task at hand. He recapped
that the PHAWG is going to pull out several of the reviewers’ comments
and attach the initial sheet as an addendum to clarify the issues that
they want ATSDR to consider. Kowetha Davidson asked how far they were
going to go on the sheet. Dr. Craig replied that they were going to go
until, “with regards to the ATSDR statement that the use of ICRP
(International Commission on Radiological Protection).” Dr. Craig
asked if there was a concise comment for this one. Dr. Davidson felt
that the PHAWG should probably only include the comments related to MRLs.
Bob Peelle stated that he had made the comment regarding the ICRP and
that he was suggesting that the report include a published reference.
Kowetha Davidson returned to the third paragraph on the first page for
clarification. She asked if the radiation measured was only coming from
Y-12, or if it was also part of the natural background. Gordon Blaylock
responded that the background radiation is what comes from nature and
is not related to Y-12. Dr. Davidson responded that she knew this, but
that she was asking if radiation measured in soil is all from Y-12. Mr.
Blaylock responded that it would not be. Dr. Davidson then stated that
if you add 360 to this measurement, you are counting part of the background
twice. She continued that 360 mrem/year is a default background level
and what they are measuring is in excess of the background; she said
that you have to know the real background.
Bill Murray replied that they could never determine the real background.
Bob Peelle concurred that if the 360 is used as a surrogate for background,
then there could be more than what was measured. Mr. Murray continued
that the closest method to obtain the real background would be to conduct
something similar to how the chemical contaminants were evaluated. Sampling
for uranium would have to be conducted somewhere that had no effect from
Y-12 or K-12, and then it would have to be assumed that the uranium levels
measured are the same as in Scarboro. Bob Craig stated that this had
been conducted. Dr. Peelle said that this has been done more than once,
but that the problem is that it is difficult to obtain the same type
of soil in this particular geographical area. Dr. Craig added that this
is why the use of a surrogate is appropriate.
Kowetha Davidson explained that the statement in the report should say
that, “the radiation doses in the report are in addition to normal
background doses.” Tony Malinauskas said that this depends on how
the data were treated and if the background was subtracted. Bob Craig
asked if a comment was going to be generated out of this. He said that
the PHAWG will ask ATSDR to clarify the doses in addition to the background,
and will attach the letter as a rationale for the four or five comments.
Dr. Davidson said that when people get into a discussion of risk, they
are going to add the radiation risk to the risk of the default background,
which is not valid. She said that they have to make sure that part of
the doses are not the same. Dr. Malinauskas agreed and said that they
have to make sure that the background is subtracted out.
Jack Hanley discussed the comment on the second page that referred to “regarding
the risk associated with an ATSDR MRL of 5,000 mrem effective dose equivalent.” Mr.
Hanley stated that this is easy to answer. The 5,000 mrem is not an MRL
and the MRL is not used to evaluate cancer. He told the PHAWG that any
clarification they can bring to these comments would be extremely helpful.
Mr. Hanley added that the person who made these comments needed to read
the document a little bit more carefully.
Bob Craig reiterated that the PHAWG is only going to ask ATSDR to respond
to four or five comments, and that they are giving a letter as an addendum
to clarify the rationale for these comments. Dr. Craig told Jack Hanley
to only deal with the PHAWG’s comments.
Gordon Blaylock stated that ATSDR’s presentation gave him the
opinion that the MRL was used for cancer effects. He believes it was
used in that manner and that if they went back to the minutes, he believes
it will be found. Mr. Blaylock asserted that this is one of the reasons
for the confusion and he thinks that these comments should be left in.
Jack Hanley stated that was fine, but that the comments needed clarification.
Kowetha Davidson asked about the middle of page three and if it was
relevant to the PHAWG’s goals. She added that the last paragraph
does not relate to the rest of the comment. Gordon Blaylock thought that
it added to the comment and should be kept in its entirety. He stated
that if Jack Hanley wants it removed, then he could remove it. Dr. Davidson
told Mr. Blaylock that Mr. Hanley would not be responding to this. Mr.
Blaylock replied that Mr. Hanley will respond to anything that the PHAWG
sends to ATSDR. Mr. Hanley responded that this was correct. Tony Malinauskas
explained that the PHAWG is going to suggest that ATSDR clarify the use
of the MRL and the 5,000 mrem/year lifetime dose. He added that providing
ATSDR with the reviewers' comments could give the agency a feel for what
is at the route of the confusion. Mr. Hanley added that any of the comments
that help ATSDR understand the reviewers’ concerns can provide
perspective.
Bob Craig asked for other technical comments. Bill Murray stated that
Tim Joseph’s comments had not been discussed yet. Tony Malinauskas
stated that he had a comment regarding the statement referring to “the
use of ICRP.” Dr. Craig responded that this will be included as
a point of clarification, as well as the use of the effective dose equivalent.
Kowetha Davidson added that the PHAWG needs to replace some of the wording
in the comments, such as changing “this reviewer” to represent
the group. The group decided to put all of Dr. Joseph’s remarks
as editorial comments.
Develop a Recommendation to the ORRHES on the Comments
Facilitator:
Bob Craig, ORRHES
Tony Malinauskas asked when the next meeting would occur. Bob Craig
responded that the next meeting is on March 3, 2003. Dr. Malinauskas
inquired whom he should send the comments to after he has made the changes.
Jack Hanley stated that Dr. Malinauskas could send the comments to him,
with the recommendation, and he will forward the materials to the appropriate
persons. Dr. Malinauskas asked Mr. Hanley when he needed the comments.
Mr. Hanley asked if he could receive them by the end of the week. Dr.
Malinauskas said that he could not have them completed by the end of
the week, but that he could have them finished by Monday, February 17,
2003. Kowetha Davidson reminded the PHAWG that they had wanted the ORRHES
to receive the comments by February 21, 2003, so Dr. Malinauskas’ deadline
would be within this timeframe.
The PHAWG prepared the following recommendation: As part of our review
of the draft PHA on Uranium from Y-12, the ORRHES recommends that the
attached comments be transmitted to ATSDR for their consideration and
response. Bob Craig asked for a motion on the recommendation. The recommendation
was unanimously approved.
New Business/Additional Comments
Facilitator: Bob Craig, ORRHES
Bob Craig asked the PHAWG for any new business. Bill Murray asked when
they would have the next PHAWG meeting. Dr. Craig suggested that the
PHAWG have a short meeting on the same date as the next ORRHES meeting,
on March 3, 2003. He said that they could meet during the break or after
the ORRHES meeting. Mr. Murray reminded the group that people would not
get paid for more than eight hours. Dr. Craig said that they could deal
with some issues if they had an hour out of the ORRHES meeting schedule.
Kowetha Davidson said that they would have to look at the ORRHES agenda
to assess if there was an available hour.
Bob Craig asked the PHAWG about suggestions for the next meeting, and
if the group would rather reschedule for February 17, 2003. Kowetha Davidson
suggested that the PHAWG discuss this with Jack Hanley to see what is
next on the agenda, and to see if another meeting could be put off until
March 17, 2003. If not, she suggested that the PHAWG have a “call” meeting
on February 24, 2003. Dr. Craig stated that there are a couple of upcoming
PHAs and that they need to be prepared for these documents.
Bob Craig said that he would talk to Jack Hanley, and that the next
meeting could be February 24, March 3, or March 17, 2003. The meeting
was adjourned at 8:00 pm.
|