Impacts of organophosphate pesticide, sumithion on water quality and benthic invertebrates in aquaculture ponds

This experiment was carried out to evaluate the effect of an organophosphate pesticide, sumithion on water and sediment quality and benthic invertebrates in aquaculture ponds for 120 days. Three treatments were tried in duplicate: no sumithion (control), weekly application of 1.0 mg/L sumithion (Low dose treatment) and 2.0 mg/L sumithion (High dose treatment). Among the different water quality parameters, transparency, NO3–N and PO4–P concentrations were significantly (p < 0.05) decreased in sumithion high dose and low dose, compared to control. The pH, organic matter (%), available phosphorus (mg/L) and total nitrogen (%) of bottom-sediment also did not vary significantly (p < 0.05) among the treatments. Seven genera of benthic invertebrates belonging to Chironomidae, Oligochaeta and Mollusca were identified over the experimental period. The abundances of benthic invertebrates (number per m2) were significantly (p < 0.05) decreased in both groups treated with summation, compared to control without pesticide. The findings suggest that sumithion had adverse effect on abundance of benthic invertebrates that might have also negative impact on culture animals in aquaculture ponds. Keywords: Aquaculture pond, Sumithion, Water quality, Sediment, Benthic invertebrates