Sub-lethal effects of environmentally relevant levels of an organophosphate insecticide on anuran larvae

My research examined the impact of exposure to a commonly used organophosphate pesticide (OP), chlorpyrifos, on tadpole cholinesterase (ChE; a frequently used enzymatic biomarker of exposure to OP pesticides), growth, and swim speed after four days in four native North American species of anurans ( Hyla chrysoscelis, Rana sphenocephala, Acris crepitans, and Gastrophryne olivacea) using laboratory tests with an environmentally realistic experimental design. This design included rive environmentally relevant concentrations of chlorpyrifos (formulated as the commercially available Dursban). I also examined if the presence or absence of pond sediment influenced tadpole responses. In two species. I further examined how a longer exposure (twelve days) influenced these same responses. Furthermore, in one species ( R. sphenocephala) I examined differences in ChE, growth, and survival in the presence of a predator between tadpoles at the same development stage exposed in the laboratory (with and without pond sediment) as well as in outdoor mesocosms. (Abstract shortened by UMI.)...