Cardiac and enzyme activity s bioindicators for pesticide effects in freshwater crabs (Poppiana dentate).

International audiencePesticides are considered to indiscriminately impact non-target biota. Populations of non-target organisms, such as crabs, face a substantial risk from pesticide exposures since their distributions extend throughout aquatic systems impacted by agricultural activities. This work addresses such impacts through the use of the bioindicators, cardiac activity and neuro-transmitter enzyme activity, with application on an indigenous crab species, Poppiana den-tata. Crabs were subjected to exposure assays involving pesticides, administered in increas-ing concentrations. Cardiac activity was non-invasively measured and percent enzyme inhi-bition was determined through the immunosorbent assay technique. Enzyme inhibition no-tably increased (49.3% to 78.6%) with pesticide concentration and neurotransmitter enzyme activities were considerably lower in pesticide-exposed crabs, versus the control group (p < 0.05). Likewise, the cardiac activities of pesticide-exposed and control crabs were significant-ly different (p < 0.05), with the highest pesticide concentrations disrupting the cardiac pat-terns of affected crabs. Therefore, these findings support the usefulness of these bioindica-tors for demonstrating the physiological and biochemical effects of pesticides on non-target, freshwater crabs, such as P. dentata