Long-term effects of bleached kraft mill effluents on carbohydrate metabolism and hepatic xenobiotic biotransformation enzymes in fish.

In a laboratory investigation, fourhorn sculpin (Myoxocephalus quadricornis) were exposed for 5-9 months to waste water from pine and birch lines from a bleached kraft pulp plant. The bleached kraft mill effluents (BKME) affected both the carbohydrate metabolism and the xenobiotic metabolism. Thus, an elevated muscle glycogen content in fish exposed to effluent from the pine pulp line suggests a metabolic imbalance. A liver enlargement and a strong elevation of the hepatic cytochrome P-450-dependent ethoxyresorufin-O-deethylase activity after exposure to the bleached pine pulp effluents indicate the presence of cytochrome P-450-inducing agents in the BKME. The results also demonstrate that many physiological test parameters may be used as good indicators of sublethal disturbances in fish to BKME exposure.