Oak Ridge Reservation: Public Health Assessment Work Group

Public Health Assessment Work Group

November 18, 2002 - Meeting Minutes

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

1. Minutes from Nov. 4, 2002 meeting
   
2. 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:
1. The thyroid's role in the human body.
2. Structural and functional abnormalities.
3. Detecting abnormalities.
4. Treatment of thyroid disease.
5. Radiation and thyroid disease.
   
3. PHAWG summary of key points of presentation (15 minutes)
   
4. F/U recommendation to Dr. Toni Bounds (TN Cancer Registry): (45 min.)
   
5. 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.
   
6. 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).
   
7. 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
   
8. New business (20 min.)
   
9. 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:

1. Decrease the amount of information on Hashimoto’s thyroiditis,
   
2. Provide written information and/or tables of the symptoms of hypothyroidism and hyperthyroidism, and
   
3. 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:

1. A source of contamination,
   
2. Evidence that the contamination has been or is being transported away from the source,
   
3. Places where people were, are, or could be exposed to contaminants from the site,
   
4. A route of exposure (inhalation, ingestion, or dermal contact) by which people are, have been, or could be exposed, and
   
5. 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.”