Assessment of genotoxic effects induced by selected pesticides on RTG-2 fish cells by means of a modified fast micromethod assay.

The cytotoxic and genotoxic effects induced by alachlor and dichlorvos, two pesticides broadly used, were studied on RTG-2 fish cell line. As measure of cytotoxicity, neutral red assay was used to determine the cellular viability. Toxicity ranking based on IC(50) values found that alachlor was more cytotoxic than dichlorvos. DNA damage has been evaluated on RTG-2 cultures by means of an in vitro assay based on the ability of PicoGreen fluorochrome to interact preferentially with double-stranded DNA (dsDNA), and the results indicated that alachlor induced DNA strand breaks at concentrations above 1.52 μg/mL, equivalent to 1/50-EC(50(48)) , whereas exposures to dichlorvos induced DNA damage only at the maximal concentrations tested 25 μg/mL (1/10-EC(50(48)) ). These results confirm the suitability of this method for the screening of genotoxic effects of this type of aquatic pollutants, and we suggest their use in hazard assessment for environmental risk procedures.