Nonylphenols in sediments and effluents associated with diverse wastewateroutfalls

Nonylphenols (NPs) have been reported to disrupt endocrine function and sex ual development in aquatic organisms at low concentrations. Environmental N P burdens are predominantly derived from degradation of nonylphenol polyeth oxylate surfactants. We detected NPs in discharge-associated riverine sedim ents adjacent to 11 of 20 active sewage treatment plants (STPs) at concentr ations up to 12,400 mu g/kg. While most previous studies have focused on ST Ps, nonylphenols were observed in association with a variety of outfall typ es. The highest sediment burden, 14,100 mu g/kg, was detected near a federa l facility's stormwater discharge. Of 75 sediments examined from 67 sites, 45% contained NP concentrations >5 mu g/kg; median concentration in these N P-positive sediments was 369 mu g/kg. Other surfactant-derived alkylphenoli c compounds, specifically 4-tert-octylphenol and 4-cumylphenol, were observ ed in two sediments at 8,220 and 70,000 mu g/kg, respectively. The maximum NP concentration detected in an effluent, 6,300 mu g/L, was from a shipyard oil/water separator. Nonylphenols were detected (> 1.0 mu g/L) in 20% of t he 59 effluents examined; 10% exceeded 10 mu g/L. Sediments sampled near a STP that had ceased treatment operations 20 years prior contained 54,000 mu g/kg, indicative of long-term NP residence. Results indicate that NPs may be released from diverse sources, concentrate in associated sediments, and persist therein for extended periods.