Acute Exposure of Caiman latirostris to the Glyphosate Commercial Formulation Roundup® Full II (66.2%): Evidence of Genotoxicity, Oxidative Stress and Endocrine Disruption

EVELYN C. LÓPEZ GONZÁLEZ; ODETTI L. M; PARAPACHU MARCO, MA.V; POLETTA, G L; SIROSKI, PABLO A.

Santa Fe

Congreso; 25th Working Meeting of the Crocodile Specialist Group; 2018

Crocodile Specialist Group

Glyphosate-based herbicides, mainly the formulation Roundup® (RU), are the mostwidely used herbicides worldwide in extensive agricultural activities, causing toxiceffects in non-target organisms, as we already demonstrated for the native crocodilespecies Caiman latirostris. We previously demonstrated that subchronic in vivoexposure to RU induces genotoxic, oxidative damage and enzymatic imbalances at thelower concentration recommended for application the in soy crops (2 %) and less. Theaim of this study was to evaluate the acute toxicity of the same formulation in order todetermine if these effects are observed after a short-term exposure to a higherconcentration and the possible underlying mechanisms. We evaluated genotoxicitythrough the presence of Micronuclei (MN) and other nuclear abnormalities (NAs): buds,notched nucleus (NN), binuclei erythrocytes (BiN), eccentric nuclei (EN), and totalnuclear abnormalities (TNA); oxidative damage to DNA through the modified cometassay by using endonucleases ENDO III and FPG and plasma corticosteronedetermination. Eight juvenile males of C. latirostris were distributed in twoexperimental groups: a negative control (NC) and a treated group exposed to theherbicide (RU). Animals were maintained under controlled conditions of temperature(30 ± 2 ºC) into plastics containers (0.57 m2 base surface) and the exposure wasperformed by voluntary immersion in water, at a concentration of 8 mg/l of RU duringone week. After exposure, blood samples were taken to all animals for the applicationof the biomarkers previously mentioned. The results indicated a significant increase ofthe FMN and BiN and the oxidation of purine and pyrimidine DNA bases, with respectto the NC (p