(IP040) Mercury in freshwater fish tissues of northeast North America: building a regional perspective.
Kamman, N1, Burgess, N2, 1 Vermont Department of Environmental Conservation, Waterbury, VT, USA2 Canadian Wildlife Service, Environment Canada, Mount Pearl, NL, Canada
ABSTRACT- As part of an initiative to assemble mercury (Hg) data from many environmental matrices across northeast North America, we analyzed a large dataset comprised of 15,606 records of fish tissue Hg data from 24 individual studies from New York State to Newfoundland. These data were summarized to provide mean Hg concentrations for 40 fish species and 6 families. Hg in fishes varied by geographic area, waterbody type, and individual waterbody. Several species displayed elevated Hg concentrations in reservoirs, relative to lakes and rivers. Standardized deviations from mean tissue levels for yellow perch (Perca flavescens) and brook trout (Salvelinus fontinalis) were evaluated using geographic information systems, illustrating the presence of areas where Hg levels in tissues of these species tended to be elevated or diminished across northeastern North America. Significant heterogeneity across the landscape was also evident. Depending on whether standard-sized yellow perch or brook trout were examined, the proportion of waterbodies exhibiting exceedances of USEPA's fish tissue methylmercury criterion ranged from 17% to 45%. Preliminary analyses of waterbody-specific factors indicated that tissue Hg burdens increased with increasing waterbody acidity and watershed size.
Key words: fish tissue, mercury, northeast USA, eastern Canada