KINETIC CONSTRAINTS IN ACUTE ALUMINUM TOXICITY IN THE RAINBOW-TROUT (ONCORHYNCHUS-MYKISS)

We have designed a laboratory bioassay to expose fish to kinetically d etermined differences in aluminium hydroxide solution chemistry. We ha ve used this system to demonstrate the hitherto unexpected result of a n acute aluminium toxicity in the fish at a pH of 6.5. Supporting expe riments have demonstrated that the mechanism of toxicity at this pH wa s probably an asphyxiation brought about by aluminium-induced changes in the rheological and diffusional properties of the mucus lining of t he gill epithelium. (C) 1996 Academic Press Limited.