Micronucleus and chronic toxicity assays to evaluate surface water genotoxicity in agricultural areas of Buenos Aires

JULIETA PELUSO; CAROLINA ARONZON; CRISTINA SILVIA PÉREZ

Buenos Aires

Congreso; SETAC-LA 2015; 2015

Agriculture is the basis of Argentine economy, and consumes large amounts of pesticides and fertilizers, which final destinies are water bodies, establishing a risk for non-target organisms. The objective of the present study was evaluate the water quality of streams associated to agroecosystems by means of toxicity bioassays in two stages of the early development and genotoxicity test (micronucleus (MN) frequency test) using premetamorphic tadpoles of native amphibian Rhinella arenarum (Ra). The study area belongs to the productive nucleus of Buenos Aires where the field crops predominate. Three sampling sites were selected in the districts of Arrecifes (A), Pergamino (P) and Salto (S). In each site, the samples were obtained from surface water. The toxicity bioassays were performed by exposing groups of 10 embryos or larvae (S.25) of Ra, for triplicate, at different dilutions of the environmental samples, assessing the lethal toxicity for 504h. In addition, for genotoxicity test, 5 premetamorphic tadpoles of Ra (S.28.), for triplicate, were exposed for 96h to non-diluted samples of the sites, a positive control of cyclophosphamide (CF) and a negative control with AMPHITOX Solution (SA) were also conducted to asses MN test on peripheral erythrocytes. For embryos, the chronic toxicity in increasing order was: (P):NOEC:100%; (S):LOEC:100% y NOEC:75% (A):LC50:45.35% and NOEC