Metals and polynuclear aromatic hydrocarbons (PAH) may be elevated around oil and gas production platforms, including those in the Gulf of Mexico (Kennicutt et al. 1996; Peterson et al. 1996). The exposure of sediment-dwelling organisms to metal and PAH mixtures may result in toxic endpoints that differ from exposure to individual contaminants. The purpose of this study was to identify acute and sublethal metal-PAH nonadditive interactions in selected benthic organisms.