Oligosarcus jenynsii as Biomonitor in La Brava Lagoon: A Battery of Biomarkers to Study Agricultural Pollution

LOMBARDERO, LR; VILLAGRAN, DM; MEDICI, SK; ITHURBURU, FG; PEREZ, DJ; CRUPKIN, AC; MENONE, ML

Congreso; 11th Young Enviromental Scientists (YES) Meeting for SETAC; 2022

SETAC

The chemical analysis alone does not reveal the impact of chemical contamination in aquatic ecosystems, instead potential effects on biota are necessary to study. The aim of this study was to evaluate pollution by agriculture by means of potential oxidative stress and genotoxicity effects in Oligosarcus jenynsii. Two samplings were carried out during one year; one in spring 2020, and another in summer 2021 during the maximum application of chemical compounds. Fish (n=20) and surface water (n=3) samples were taken in each sampling. The activities of the enzymes Catalase (CAT) and Glutathione-S-transferase (GST) were measured, as well as the levels of Malondialdehyde (MDA) in brain, liver and gills and hydrogen peroxide (H2O2) level in liver and gills (all spectrophotometrically). In addition, the frequencies of micronucleous (MN) and other nuclear abnormalities were quantified in erythrocytes using optical microscope. Water samples were analyzed by UPLC-MS/MS to quantify current use pesticides. The results show that CAT activity in liver and GST in the three organs studied were higher in summer than in spring; while MDA in gills was lower in summer than in spring. There was no differences between seasons in H2O2 or MN. In spring, several pesticides were found at low concentrations (chlorpyrifos, glyphosate and AMPA), and in summer only chlorpyrifos at a maximum concentration of 2.3 µg/L. The present study shows the utility of antioxidant enzymes as biomarkers associated to environmental levels of chlorpyrifos. It also allows including this type of research in a comprehensive management plan to be carried out in this protected area.