Accumulation of heavy metals in rainbow trout Salmo gairdneri (Richardson) maintained on a diet containing activated sewage sludge

Abstract

Rainbow trout were fed for 10 weeks with a nutritionally balanced diet containing 30% by weight of activated sewage sludge. The whole body concentrations of nine heavy metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb), together with four major cations (Ca, Mg, Na, K) were determined at the beginning and end of the experiment and at three intermediate stages. Fish fed on the diet containing sewage sludge had significantly elevated levels of Cr, Fe, Ni, Pb and reduced levels of Na and K compared with controls, though the values obtained for all groups fell within the range reported for uncontaminated fish. The Ni and Zn showed a marked increase towards the end of the experiment, suggesting that they might have continued to rise after 70 days.

The role of sediments in the chemistry of aquatic systems - Proceedings of the sediment chemistry workshop, February 8-12, 1982

“…More uptake from food and water than from water alone was also observed for Fe by mussels and shrimp (Fowler and Benayoun, 1976), Ag by estuarine clams (Amiard, 1978), Co by freshwater fish and crayfish (Amiard-Triquet, 1979), and Hg in salmon and trout (Spinelli and Mahnken, 1976;Hartman, 1978;Phillips and Buhler, 1978). Singh and Ferns (1978) observed uptake of Mn, Co, Cu, Cr, Ph, Zn, Ni, and Cd in trout fed metal-contaminated activated sludge or commercial pellets.…”