PRELIMINARY-OBSERVATIONS ON THE HEAVY-METAL CONTENT OF 4 SPECIES OF FRESH-WATER FISH IN NW ENGLAND

Concentrations of [the environmental pollutants] Zn, Pb and Cd in 4 spp. [Esox lucius and the 3 following] of fish from several lacustrine sites were determined. Cyprinids had significantly higher levels of these metals studied than perch, Perca fluviatilis. While Zn thresholds may be species-specific, levels of Pb and Cd vary both within species and sites. There is some evidence that Pb and Cd levels increase with age in roach, Rutilus rutilus. Cd and Pb appear to accumulate in the heart, liver, kidney, brain and bone. Relatively high levels of Pb and Cd were recorded in the eyes of bream, Abramis brama.