Azinphos methyl-induced changes in Jenynsia multidentata gills

GUERREÑO M.; VENTURINO A; LUQUET C; LÓPEZ ARMENGOL M.F.

Buenos Aires

Congreso; 11th Biennial Meeting Society of Environmental Toxicology and Chemistry (SETAC) Latin America; 2015

SETAC LA

Theintensive fruit production in Río Negro valley leads to the massive use oforganophosphorus (OP) pesticides. The purpose of this study was to determinethe toxic effects of the OP azinphos methyl  (AZM) in Jenynsiamultidentata gills. Static sublethal exposures to 5 and 10 µg/LAZM of adult female J. multidentata were made during 96hours. Histopathological alterations were evaluated throughhematoxylin-eosin staining and optical microscopic . Reactive oxygen species(ROS) were determined by fluorometric imaging (ex/em: 485/520 nm) using2′,7′-dichlorofluorescein diacetate (H2DCF-DA) and quantifying digital imageswith ImageJ 1.49o program version. Significant differences (p = 0.0233, nonparametricKruskal-Wallis test) were assessed for ROS production in gills as aresult of AZM exposure. Post hoc test indicated that ROS measured in gills ofthe animals exposed to 10 µg/L AZM  were significantly higher than thosefrom control ones (p <0.046). Regarding to histopathological changes in therespiratory lamellae, we found intraepithelial edema, hemorrhages, enlargedblood spaces and fusion of some lamellae. In the primary lamellae, cellproliferation and hyperplasia were found. These results demonstrate the highsusceptibility of J. multidentata to one of the  agrochemicals actually used in the region, AZM, leading to deleterious effectseven at exposures to sublethal concentrations.