Computing Maximum-Likelihood Estimates for Parameters of the National Descriptive Model of Mercury in Fish.

摘要

The National Descriptive Model of Mercury in Fish Tissue (NDMMF) is a statistical model (Wente, 2004) used to predict the concentration in fish tissue of methylmercury, a potent neurotoxin and a known health hazard for humans and wildlife. The utility of the NDMMF derives from its power to explain much of the observed variation in fish-tissue methylmercury concentrations as (1) variation by geographic location, (2) variation over time, and (3) variation by species and fish length due to bioaccumulation. Because it is based on a national database of methylmercury observations, this model has the potential to be used locally throughout the conterminous United States and in parts of Canada for planning ongoing sampling of methylmercury in fish, and for preparing public health warnings (fish consumption advisories) identifying specific species and sizes of fish from particular locations known or likely to be high in methylmercury content (Hearn and others, 2006).