Mercury toxicity: biochemical and physiological alterations in nine freshwater teleosts.

Nine fish species subjected to various concentrations (5, 10, 15 and 20 ppm) of mercuric nitrate for 4.5 h. The relationship between the concentrations of mercuric nitrate and the fall in renal glycogen was inverse. There was an elevation in liver and muscle glycogen at 5 ppm mercury. Brain glycogen increased to less than 10 ppm and then decreased. Glucose and lactate levels increased with increasing concentration of mercury, and muscle, liver, kidney and brain glycogen decreased. The effects were more marked in major carp than in the other species.