Uncertainties in the reference dose for methylmercury.
This paper critically examines the National Academy of Sciences and the National Research Council report on the toxicological effects of methyl mercury and the recently published US Environmental Protection Agency Reference Dose (RfD) for Methylmercury. Particular scrutiny is placed on the choice of the critical study and the underlining assumptions utilized in the selection of specific uncertainty factors (UFs) and the rationale for using a less-than-default factor of 10. The UFs that were utilized or considered by other agencies and organizations are also critically examined, explained and compared to one another. Based on these analyses, the authors suggest research that could be performed that would ameliorate the uncertainty of choosing a more precise partial UFor that may even provide completeness of database to allow for selecting of a UF for unity, thus improving the precision of the current published RfD.
Dourson
M L
ML
Toxicology Excellence for Risk Assessment, Cincinnati, OH 45223, USA. dourson@tera.org
Wullenweber
A E
AE
Poirier
K A
KA
D000818:Animals; D004341:Drug Evaluation / Q000379:methods / Q000592:standards; D006801:Humans; D008767:Methylmercury Compounds / Q000008:administration & dosage* / Q000592:standards* / Q000633:toxicity; D009307:National Academy of Sciences, U.S.; D011640:Public Policy; D012015:Reference Standards; D018570:Risk Assessment; D014481:United States; D014484:United States Environmental Protection Agency
D008767:Methylmercury Compounds