Mercury levels in muscle tissues of preserved museum fish

Determination of total mercury levels in 57 preserved fish specimens of various species collected in the lake St. Clair - western lake Erie region of the Great Lakes between the years 1920-1965, showed that only five fish contained mercury in excess of 0.5 p.p.m. A trend was established between mercury content of selected categories of fish and the year and location for the fish specimens. The 1970-71 mercury levels in fish from the two study areas were found to average more than those in preserved museum specimens in the same categories taken from the same area. Species on the highest trophic level, such as the sea lamprey, generally had the highest mercury levels.