Parhyale hawaiensis as a promising alternative organism for monitoring acute toxicity of sediments under the influence of submarine outfalls

One option for effluent discharge is the ocean because of its high depuration and dilution capacity. However, this practice may have negative impacts on aquatic biota. The objective of this study was to develop a miniaturized sediment acute toxicity test using the amphipod Parhyale hawaiensis and to verify its suitability to monitor sediment samples under the influence of a submarine outfall. Samples from Santos Bay were evaluated as whole sediment, dry sediment, pore water, aqueous and organic extract. Sediment samples were tested in 12-wells microplates and liquid samples in 96-wells microplates. Toxicity was observed in 73% of the whole sediment samples, in agreement with the literature for the same study area. Aqueous extracts showed no toxicity, but pore water and organic extract were toxic, suggesting that toxicity is related to organic contaminants. The miniaturized acute toxicity test with P. hawaiensis proved to be a promising tool for monitoring marine environments.