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

PARACHÚ MARCÓ, MA. VIRGINIA; ODETTI, LUCÍA; SIROSKI, PABLO ARIEL; LÓPEZ GONZÁLEZ EVELYN C.; POLETTA, GISELA L.

Santa Fe

Congreso; 25th Working Meeting of the Crocodile Specialist Group (SSC-IUCN); 2018

Crocodile Specialist Group (SSC-IUCN)/Universidad Nacional del Litoral

Glyphosate-based herbicides, mainly the formulation Roundup® (RU), are the most widely used herbicides worldwide in extensive agricultural activities, causing toxic effects in non-target organisms, as we already demonstrated for the native crocodile species Caiman latirostris. We previously demonstrated that subchronic in vivo exposure to RU induces genotoxic, oxidative damage and enzymatic imbalances at the lower concentration recommended for application the in soy crops (2 %) and less. The aim of this study was to evaluate the acute toxicity of the same formulation in order to determine if these effects are observed after a short-term exposure to a higher concentration and the possible underlying mechanisms. We evaluated genotoxicity through the presence of Micronuclei (MN) and other nuclear abnormalities (NAs): buds, notched nucleus (NN), binuclei erythrocytes (BiN), eccentric nuclei (EN), and total nuclear abnormalities (TNA); oxidative damage to DNA through the modified comet assay by using endonucleases ENDO III and FPG and plasma corticosterone determination. Eight juvenile males of C. latirostris were distributed in two experimental groups: a negative control (NC) and a treated group exposed to the herbicide (RU). Animals were maintained under controlled conditions of temperature (30 ± 2 ºC) into plastics containers (0.57 m2 base surface) and the exposure was performed by voluntary immersion in water, at a concentration of 8 mg/l of RU during one week. After exposure, blood samples were taken to all animals for the application of the biomarkers previously mentioned. The results indicated a significant increase of the FMN and BiN and the oxidation of purine and pyrimidine DNA bases, with respect to the NC (p