• As data become available, exposure to elemental Hg from dental amalgams should be considered in risk assessment of MeHg. Exposure to other chemical forms of Hg should also be considered.

• Retention of inorganic Hg in the brain for years following early MeHg intake is possibly related to the latent or long-term neurotoxic effects reported. The long half-life of inorganic Hg in the brain following MeHg intake should be considered in risk assessment of MeHg.

• The mechanisms, including any enzymes, involved in the biotransformation of MeHg to mercuric Hg in human tissues need to be investigated, especially at the subcellular level. The effects of Hg on signaling pathways and the conformation of enzymes and structural proteins should be further elucidated, because the development and function of the brain would be particularly sensitive to such effects.

• Exposure assessment of the U.S. population — including those with high fish consumption — is needed to provide a full picture of the distribution of MeHg and total Hg exposure nationally and regionally.

Aaseth, J., D. Jacobsen, O. Andersen, and E. Wickstrom. 1995. Treatment of mercury and lead poisoning with dimercaptosuccinic acid and sodium dimercaptopropane-sulfonate: A review. Analyst120(3):853-854.

Aberg, B., L. Ekman, R. Falk, U. Greitz, G. Persson, and J.O. Snihs. 1969. Metabolism of methyl mercury (²⁰³Hg) compounds in man. Arch. Environ. Health 19(4):478-484.

American Academy of Pediatrics. 1999. Thimerosal in vaccines — An interim report to clinicians. Committee on Infectious Diseases and Committee on Environmental Health . Pediatrics 104(3):570-574.

Aposhian, H.V. 1983. DMSA and DMPS: Water-soluble antidotes for heavy metal poisoning. Annu. Rev. Pharmacol. Toxicol. 23:193-215.

Aposhian, H.V., and M.M. Aposhian. 1990. Meso-2,3-dimercaptosuccinic acid: Chemical, pharmacological and toxicological properties of an orally effective metal chelating agent. Annu. Rev. Toxicol. 30:279-306.

Aposhian, H.V., D.C. Bruce, W. Alter, R.C. Dart, K.M. Hurlbut, and M.M.

Front Matter (R1-R20)

Executive Summary (1-12)

Introduction (13-30)

Chemistry, Exposure, Toxicokinetics, and Toxicodynamics (31-71)

Biological Variability (72-104)

Dose Estimation (105-146)

Health Effects of Methylmercury (147-249)

Comparison of Studies for Use in Risk Assessment (250-270)

Dose-Response Assessment (271-303)

Risk Characterization and Public Health Implications (304-332)

Appendix to Chapter 7 (333-336)

Glossary (337-344)