MODERN PESTICIDES: NEW CHALLENGES IN ECOTOXICOLOGY

J.C. BRODEUR

Jornada; Jornadas de la Sociedad Argentina de Biología; 2014

Pesticides are the only man-made contaminants deliberatelyreleased into the environment.  Fiftyyears ago, the obvious environmental impacts of legacy pesticides(organochlorines and organophosphates) were key elements in promoting theemergence of ecotoxicology as a scientific discipline.  The first decades of ecotoxicology studies ledto the establishment of standardized test protocols, toxicity endpoints andrisk assessment procedures that are nowadays essential for evaluating newpesticide molecules. Nevertheless, although the procedures currently employedin pesticide ecotoxicology are useful, they remain far from being ideal.  For example, while laboratory exposures arecontinuous and to a single chemical, ecosystems are normally exposed in pulsesand to various pest products simultaneously.  Classical test designs are also ineffective at predicting situationswhere trophic interactions and indirect effects may operate, and the detectionof negative effects caused by low-level persistent contamination remains achallenge.  Pesticide ecotoxicology needsto get beyond its actual limitations and incorporate a greater level of fieldrealism into its assessments.  In themeantime, ecotoxicologists risk assessors, industrials, and governments need tobe conscious of our actual limitation to truly assess the impacts pesticidesmay have in the environment once they are released.