Genotoxic evaluation of the pyrethroid lambda-cyhalothrin using the micronucleus test in erythrocytes of the fish Cheirodon interruptus interruptus

In order to develop experimental models able to detect genotoxic effects of pollutants in aquatic organisms, the genotoxicity of the pyrethroid lambda -cyhalothrin was studied using the micronucleus test in erythrocytes of Che irodon interruptus interruptus. The frequency of micronuclei was examined i n blood smears obtained from fishes exposed in vivo to three different conc entrations (0.05; 0.01; 0.001 ug/l) of the compound and sacrificed at nine sampling times (24, 48, 72, 96 h and 8, 12, 15, 19 and 23 days). As a posit ive control fishes were exposed to 5 mg/l of cyclophosphamide. Results obta ined demonstrated the genotoxic effects of the pyrethroid in the experiment al model employed, The variation in the micronuclei frequencies in the diff erent sampling times could be related to the blood cell kinetics and the er ythrocyte replacement. The results could be considered as a validation of t he MN test in fishes for the assessment of genotoxic pollutants. (C) 1999 P ublished by Elsevier Science B.V. All rights reserved.