Some effects of exposing rainbow trout (Salmo gairdneri Richardson) to phenol solutions

Phenol (C₆H₅OH) at non-lethal concentrations in hard water had no effect on the urine flow rate or haematocrit of rainbow trout for exposure times of 24 h. Phenol was detected in the urine in a non-conjugated form and unchanged phenol was also extracted from muscle, blood and brain. Uptake of phenol into tissue was found to be rapid with an equilibrium concentration being reached in 3 h. Loss of phenol after exposure was as rapid. The equilibrium concentration for muscle was similar to the phenol concentration to which the fish were exposed. Blood and brain contained smaller amounts. Close to or above the lethal threshold concentration (48-h lc₅₀9 mg 1^-l; 15°C) the fish had higher than ambient concentrations in their tissues most notably in the brain. Above the lethal threshold there is evidence of a large uptake of phenol by erythrocytes.