Citotoxicity and genotoxicity on Caiman latirostris (Broad-snouted caiman) exposed to the insecticide Chlorpyrifos and a complex pesticide mixture widely used in extensive agriculture.

LÓPEZ GONZÁLEZ EVELYN C.; SIROSKI PABLO A.; LARRIERA ALEJANDRO ; ROMITO, MA LAURA; POLETTA GISELA L.

Skukuza

Congreso; 24th Working Meeting of the Crocodile Specialist Group (SSC-IUCN); 2016

Crocodile Specialist Group IUCN/CSG

The aim of this study was to evaluate the cytotoxicity and genotoxicity induced by the insecticide Chlorpyrifos- (CPF) based formulation (Lorsban 48E® -48%) and a complex pesticide mixture consisiting of the insecticide Cypermethrin (Atanor® -CYP, 25%) + CPF + the herbicide Glyphosate (Roundup Full II® -GLY, 66.2%) on C. latirostris hatchlings.Sixty-four C. latirostris hatchlings, 20 days old, from four different clutches, were randomly distributed into four experimental groups (16 specimens per group with two replicates each): 1) a vehicle control (VC: 200 µl/L) treated with ethanol; 2-3) two groups exposed to different concentrations of CPF (CPF1: from 0.5 to 0.05 µg/L and CPF2: from 1 to 0.1 µg/L); and 4) a group treated with the complex mixture (M): CYP1 (from 0.5 to 0.05 µg/L) + CPF1 (from 0.5 to 0.05 µg/L) + RU1 (from 2.5 to 0.25 mg/L). Animals were maintained in plastics containers with the corresponding solutions (exposure by immersion) during two months, with a progressive decrease in all pesticide concentrations, in order to simulate their degradation in water through time, in natural conditions.After exposure, blood samples were taken to all animals for the determination of Neutral Red uptake (NRU) and MTT metabolism as cytotoxicity assays; while the Frequency of Micronuclei (FMN), Nuclear Abnormalities (NA) and DNA damage index (DI) through the Comet Assay (CA) were applied on erythrocytes as biomarkers of genotoxicity.In relation to cytotoxicity, NRU was significantly lower for group M respect to NC (p=0.043), but no differences were observed in MTT metabolism. Genotoxicity results indicated a significant increase in the FMN in caimans exposed to both concentrations of CPF (p