Hepatic Metallothionein in Rainbow Trout (Salmo gairdneri) as an Indicator of Metal Pollution in the Campbell River System

Abstract

Hepatic metallothionein was measured in livers of freshly killed rainbow trout (S. gairdneri) using differential pulse polarography. The fish were caught in metal-contaminated lakes of the Campbell River watershed and in a nearby control lake. The livers were analyzed for Zn, Cu and Cd using atomic absorption spectrophotometry. High and low MW protein fractions were separated by gel chromatography from liver cytosols and analyzed for metals. A downward trend from the most contaminated lake to the least was found in levels of Zn in the water, of Cd and Cu in high MW fractions and of Cu in low MW fractions and metallothionein. The concentration of metallothionein was a useful quantitative measure of the degree of exposure of fish to heavy metals.