Effects of oral doses of the herbicide atrazine of carp (Cyprinus carpio)

The wide use of herbicides in agriculture leads to contamination of the environmental biotope via runoff into lakes and ponds. Impacts on fish species such as cyprinids, either wild or raised on fish farms, can be expected. Food containing 10, 100 or 1000 ppm of atrazine, a commonly employed triazine herbicide, was fed to carp for up to 2.5 months (84 days). The concentration of atrazine in whole body, liver and lymphoid organs was determined. On day 84, only the kidney was slightly contaminated. No effect of atrazine was observed for two aspects of immunological response: splenic index, and antibody production against Yersinia ruckeri bacteria in sera. After 84 days, few variations were shown in the total liver-glycogen reserves and the activity of liver neoglucogenic enzymes (stress indicator). Hepatic cytochrome P-450 content and monooxygenase activity were not modified, neither was blood glucose. In muscle, no changes were observed in lipidic composition of membranes, but the activities of membrane-bound enzymes were disturbed after 14 days at 1000 ppm. Levels of sialic acid in corporal mucus were always decreased in intoxicated carps. Thus, atrazine intoxication via food induces slight and reversible perturbations, which do not seem to affect fish life or the quality of fish as a source of human food.