Genotoxic and cytotoxic effects of the formulated insecticide Aficida® on Cnesterodon decemmaculatus (Jenyns, 1842) (Pisces: Poeciliidae)

The acute toxicity, genotoxicity, and cytotoxicity of the pirimicarb-containing commercial-formulation carbamate insecticide Aficida (R) (50% pirimicarb) were evaluated on Cnesterodon decemmaculatus (Pisces, Poeciliidae) exposed under laboratory conditions. Micronucleus (MN) induction as well as alterations in the erythrocytes:erythroblasts ratios were employed as end-points for genotoxicity and cytotoxicity, respectively. Cr(VI) and cyclophosphamide were used as positive controls for the toxicity and geno-cytotoxicity assays, respectively. Mean values of 344.3 and 225.5 mg Aficida (R)/L were determined for LC-50(24h), and LC-50(96h), respectively. In 48 h-exposed fish, a MN increase was found in Aficida (R)-treated fish in the 50-157 mg/L concentration range. When fish were exposed to Aficida (R) for 96h. only those animals treated at 50-100 mg/L showed an increase in MN frequency. Cellular cytotoxicity, revealed by a decreased proportion of circulating erythrocytes and an enhancement of erythroblasts, was found after 48 h of exposure in 50-157 mg Aficida (R)/L-treated fish, while, after 96 h exposure, only 100-157 mg Aficida (R)/L induced the same effect. This species provides a useful experimental model for the biomonitoring of aquatic ecosystems. (C) 2010 Elsevier B.V. All rights reserved.