Cadmium
Cadmium is a nonessential element that can be both carcinogenic and toxic to aquatic biota.
Cadmium has been shown to adversely affect invertebrates by inhibiting calcium influm. In fish, cadmium has been shown to adversely affect esvesal enzyme systems,
-neurotransmission / transepithelial transport/ intermediary metabolism and mixed-function oxidase/antioxidant activity