Health impact of combined pesticide exposures
Résumé
Occupational or environmental exposure to pesticides is a public health concern. Numerous epidemiologic studies show that occupational exposure to these substances is positively correlated with an increased risk of developing certain diseases. Epidemiologic studies among consumers of organic food products (which have greatly reduced pesticide levels) show an inverse relation with the rates of some cancers and metabolic diseases. Experimental studies provide arguments of a plausible link between pesticides and health. Pesticides are biologically active compounds that can individually exert specific effects on different targets that play a major role in cellular function and by extension in the physiological functions of the body. Consumers are exposed to low doses of mixtures of pesticides. When combined, they can interact with one another and induce synergistic effects. Their interactions are complex phenomena involving a network of targets and mechanisms at both the cell and organ levels. It is thus difficult to predict the effects of any given pesticide cocktail, given the diversity of their effects and interaction levels and of the organism's adaptability and biological responses.