National Toxicology Program

Notice of workshop on "Scientific Issues Relevant to Assessment of Health Effects from Exposure to Methylmercury", November 18-20, 1998, at the Brownestone Hotel in Raleigh, North Carolina.

At the request of the White House Office of Science and Technology an interagency committee has organized the subject workshop to discuss and evaluate the major epidemiological studies associating methylmercury exposure with an array of developmental measures in children. The organizing committee is chaired by the National Institute of Environmental Health Sciences, National Institutes of Health, with representatives from the Environmental Protection Agency, the Agency for Toxic Substances and Disease Registry, the Food and Drug Administration, the Department of Health and Human Services, the National Oceanic and Atmospheric Administration, the Office of Science and Technology Policy, and the Office of Management and Budget.

The major studies being considered at the workshop are those which have examined populations in Iraq and the Seychelles, the Faeroe Islands, and the Amazon, along with the most relevant animal studies for estimating human risks. Workshop participants will try to reach consensus on what we can conclude and what the uncertainties are for each of the studies alone and for the studies taken together. The product of the workshop should be policy relevant and facilitate agreement on risk assessment issues.

Scientists involved in the major studies will present and discuss their studies. To help structure the workshop the following questions have been developed by the organizing committee and will be discussed with respect to each study:

1. For each study, what are the relative exposures to organic or inorganic mercury?
2. What are the sources of exposure? Is the consumption of fish, shellfish and marine mammals the dominant source? Are dental amalgams, occupational exposures or other sources significant confounders?
3. What is the specificity and sensitivity of health endpoints, e.g., behavioral, neurological, and developmental? What are the most specific and sensitive tests of these endpoints? How are these tests impacted by cultural or behavioral practices?
4. Are the developmental tests used comparable across different studies? Across species?
5. What are the confounders that affect health endpoints positively (e.g., selenium, omega-3 fatty acids) and negatively (e.g., PCBs; alcohol use; health conditions with neurological effects, such as diabetes)? Do they influence the interpretation of the study.
6. What is the variability within and across populations studied in mercury exposure and host factors (e.g., age, gender, nutritional status and practices, and genetic predisposition)?
7. For each epidemiological study of interest, which features of its statistical design, research protocol or execution in the field are particularly strong or weak? To what extent do these strengths and weaknesses affect the validity and reliability of scientific inferences based on these studies?
8. What are the contributions of animal or experimental studies toward interpretation of the human studies?

Organized panels will assess the presentations with respect to the questions above. A panel on exposure will assess and develop a report on questions 1 & 2; a neurobehavioral panel will assess and develop a report on questions 3 & 4; a panel on confounders and variables will address 5 & 6; and a panel on design/statistics will assess and report on question 7; question 8 will be addressed by the experimental panel.

Invited workshop participants will include scientists involved in the major studies, epidemiologists, pediatric neuropsychiatrists, developmental biologists, toxicologists, biomathematicians, biomonitoring specialists and scientists who are skilled at integrating diverse data sets, as well as representatives from Federal and State agencies who are involved in assessing risks from methylmercury exposure.

A public comment session will provide the opportunity for additional views and comments. Oral presentations will be limited to 5 minutes in length to allow for a maximum number of presentations. Written statements should supplement and may expand on the oral presentation. Written comments may also be provided and should be submitted to the NTP Liaison & Scientific Review Office, NIEHS, P.O. Box 12233, Research Triangle Park, NC 27709 and must be received by November 9, 1998, to be transmitted to the workgroups prior to the workshop.

The general sessions and the breakout groups are open to the public and limited only by the space available. A public comment session is scheduled as described above. Oral and/or written comments are requested as discussed above.

To register, please provide the following information: to the Workshop on "Scientific Issues Relevant to Assessment of Health Effects from Exposure to Methylmercury"

"Scientific Issues Relevant to Assessment of Health Effects from Exposure to Methylmercury"

Brownestone Hotel
Raleigh, NC

November 18-20, 1998

Please mail or fax your registration, no later than November 6, 1998 to:

NTP Liaison & Scientific Review Office
NTP/NIEHS
P.O. Box 12233
MD: A3-01
Research Triangle Park, NC 27709
fax: (919) 541-0295

I am interested in observing the following break-out group discussion:

"Breakout" Panel Sessions: (Please mark first and second choices)

1. Exposure Panel_______________________________
2. Neurobehavioral Endpoints Panel______________
3. Confounders & Variables Panel________________
4. Design/Statistics Panel________________________
5. Experimental Panel___________________________

Public Comment Session:

I would like to make an oral presentation during the Public Comment Session:
_______________________
(limit to 5 minute oral presentation, written statements should supplement and may expand on the oral presentation)

A registration fee of $50.00 (US) is requested. Credit cards cannot be accepted. Personal checks, cashier checks or money orders made payable to: Methylmercury Workshop should be included with your registration. For those faxing registration, please indicate the date the registration fee is being fowarded by mail.

Hotel reservations can be made directly with the Brownestone Hotel (919) 828-0811. A block of rooms is being held through October 30, 1998. Identify yourself as attending the NIEHS Methylmercury Workshop.

Dated: October 21, 1998



_______________________________
Samuel H. Wilson, M.D.
Deputy Director, NIEHS