Uptake, distribution in different tissues and genotoxicity of imidacloprid in the freshwater fish Australoheros facetus

ITURBURU, GF; ZOMISCH, MARKUS; PANZERI, A.; CRUPKIN, A; CONTARDO-JARA, VALESKA; PFLUGMACHER, STEPHAN; MENONE, MIRTA L

ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY

SETAC PRESS

Lugar: Buenos Aires; Año: 2016

0730-7268

The neonicotinoid imidacloprid (IMI) is nowadays under re-evaluation by regulatory agencies because of the poor current information available regarding its potential effects. One of the goals of the present work was to determine IMI uptake and distribution in the freshwater fish Australoheros facetus experimentally exposed during 24 and 48 h to 100, 300 and 2500 µg/ L. The toxicity of IMI to fish reported in the literature is in the mg/L or g/L range, but sub-lethal effects at µg/L in some groups other than fish have been described. Another goal of the present study was to evaluate its potential genotoxicity and to compare it between the individual compound and a commercial formulation. Concentrations of IMI were measured in water, brain, muscle, gills, gut, liver and blood by LC- MS/MS. IMI was detected in all the tissues tested. Concentrations were higher after 48 h than after 24 h in liver, gills, gut and muscle, while in brain and blood they were similar at both exposure times. Although there was not accumulation, only uptake of IMI, genotoxicity was observed. In fish exposed to the IMIDA NOVA 35®, increased micronucleus frequency at 100 and 1000 µg/L was detected while in the IMI active ingredient bioassay it increased only at 1000 µg/L IMI. Our findings warn of the possible consequences that fish living in freshwater ecosystems can suffer.