Concentration of current-use pesticides in frogs from the Pampa region and correlation of a mixture toxicity index with biological effects.

Contamination with current-use pesticides is frequently mentioned as a key factor in global amphibian declines although a limited number of studies have examined the mixture of pesticides accumulated by free-living frogs. This study examined the presence of 46 different pesticide residues in the muscle and kidney tissues of two frog species living in close association with row crops in the Pampa region of Argentina: The terrestrial Leptodactylus latinasus and the semi-aquatic Leptodactylus latrans. A total of 20 different pesticides were identified in frog tissues; chlorpyrifos-methyl, pirimiphos-methyl and acetochlor being the most frequently detected molecules.

Accumulation of current-use pesticides, cholinesterase inhibition and reduced body condition in juvenile one-sided livebearer fish (Jenynsia multidentata) from the agricultural Pampa region of Argentina.

The aim of this study was to characterize the level and nature of the pesticide contamination received by one-sided livebearer fish (Jenynsia multidentata) from a watercourse situated within the main agricultural region of Argentina, and to assess the effects of this contamination on fish health. Juvenile one-sided livebearer fish (Jenynsia multidentata) were collected in December 2011 and March 2012 from three sites along the Pergamino River. Pesticide contamination was characterized by extracting whole fish and analytically determining thirty different pesticide molecules.