DDT concentration in fish from the Tapajós River in the Amazon region, Brazil

Abstract

DDT and metabolites were measured in six species of fish collected from the Tapajós River in the village of Barreiras, near the town of Itaituba in the Brazilian Amazon region. The selected fish were the most consumed and economically important to the local people. DDT was used frequently in this region for malaria control. Fish samples were analyzed after extraction by microwave-assisted extraction in hexane/acetone (8:2, v/v) by gas chromatography with electron capture detector. Residues of op′-DDT and pp′-DDT and metabolites were detected, including pp′-DDE, pp′-DDD, op′-DDT, and op′-DDE, in 98 per cent of the samples, with a greater abundance of pp′-DDT. Total DDT levels were 7.1û249.5 ng g−1 wet weight (w.w). The DDE/DDT ratio was low, indicating recent exposure to DDT. The study area that may be related to generated waste used in public health campaigns to combat mosquitos (Anopheles spp.), still present in the Amazon environment, that transmit malaria. DDT levels and metabolites found in fish species do not present risks to human health because they are below acceptable limits for consumption.