Surfactants in sediments

There is a general paucity of literature data dealing with surfactants moni toring in sediments using specific methodologies. The only surfactants for which a consistent data set already exists are Linear Alkylbenzene Sulphona te (LAS) and Nonyl Phenol Ethoxylate (NPE). Concentrations of LAS and NPE, have in fact been monitored in both fresh wafer and marine sediments and we re generally found to range from 0 to 5.0 mg/kg. Higher levels were reporte d only for some sediments collected close to untreated or inadequately trea ted sewage effluent discharges. This paper reviews the existing monitoring data for these surfactants in sediments and also reports the preliminary re sults of a recent monitoring programme carried out on the bottom sediments of the main watercourse in Italy, the river Po, using HPLC methodologies. F or the first rime, attention has been focused not only on LAS but also on A lcohol Ethoxylate (AE). To our knowledge this is the first example of a con centration-specific estimate of AE in sediments. These results will be disc ussed and compared with the limited toxicity information which is available on benthic organisms.