Premetamorphic anuran tadpoles as test organism for an acute aquatic toxicity assay

An acute semistatic bioassay method for the evaluation of water quality in highly polluted river samples is described. Bufo arenarum young tadpoles as test organism were used. This anuran is a species of the native herpetofauna of Argentina. The technique was checked with surface water samples of Reconquista River, collected from four sites along the low-to-high pollution gradient. The controls were run with artificial hard water. The sensitivity of tadpoles to toxicants was checked by incubation of test animals in sublethal and lethal cadmium solutions as a standard toxicant. Mortality was registered daily for 96 h and the results were expressed as cumulative mortality. Statistical analysis was carried out by means of a multiway factor analysis of variance with Bonferroni range test. Each assayed sample was chemically analyzed in order to determine the content of heavy metals, and organochlorine and organophosphorous insecticides. This bioassay did allow us to discriminate clearly between high and low polluted samples showing a good toxicological correlation with the determined chemical profile. © 1997 by John Wiley & Sons, Inc. Environ Toxicol Water Qual 12: 117–121, 1997