Toxicity of sediment associated PAHs to the estuarine crustaceans, Palaemonetes pugio and Amphiascus tenuiremis

The potential toxicity of sediment-associated PAH was investigated using the larval stage of the grass shrimp, Palaemonetes pugio, to assess acute mortality (LC50) and the benthic copepod, Amphiascus tenuiremis, to evaluate PAH sublethal reproductive effects. Calculated 96 and 168 h LC50 values for P. pugio were 9542 and 6464 ng PAH per g dry sediment, respectively. Parental male and female copepod survival was unaffected until at 1211 ng PAH per g, female survival was reduced by 24 per cent. Mean clutch size was reduced to 83.7 per cent of control values in 1211 ng PAH per g treatments. Consistent dose:response trends apparent in the number of nauplii and copepodites per surviving female, and the calculated potential effects on reproduction, indicated that PAH possibly affected reproduction at levels which were normally thought to be non-effect levels. Copepod results were in general agreement with other studies. P. pugio was more sensitive to PAH mixtures than A. tenuiremis.