title: Concentrations of trace substances in sewage sludge from 28 wastewater treatment works in the UK.
abstract: Concentrations of trace substances in sewage sludge have been measured in a survey of 28 wastewater treatment works (WwTWs) in the UK carried out over a period of 12months. Approximately 250 samples were analysed for more than 40 trace contaminants, including trace metals, pharmaceuticals, polycyclic aromatic hydrocarbons (PAHs), 'emerging' and regulated organic pollutants. All substances investigated were found to be present in at least some of the sludges sampled. Concentrations were relatively homogenous across all the WwTWs, irrespective of the treatment process, influent and effluent concentrations, and the location of the sludge sampling point within each works. Analysis of the results against existing regulatory and proposed thresholds suggested that levels are mostly below the limits set in the Sewage Sludge Directive, and proposed new limits for sludge used in agriculture. Predicted soil concentrations after application of sewage sludge to land were below the predicted no effect concentrations (PNEC) for all determinands. Predicted concentrations of pharmaceuticals in soil were also below thresholds deemed to indicate negligible environmental risk.
authors.affiliation: Atkins Limited, The Hub, 500 Park Avenue, Aztec West, Bristol BS32 4RZ, UK. Electronic address: vera.jones@atkinsglobal.com.
authors.forename: Vera
authors.initials: V
authors.lastname: Jones
authors.affiliation: Atkins Limited, The Hub, 500 Park Avenue, Aztec West, Bristol BS32 4RZ, UK.
authors.forename: Mike
authors.initials: M
authors.lastname: Gardner
authors.affiliation: UKWIR, Queen Anne Gate, London SW1H 9BT, UK.
authors.forename: Brian
authors.initials: B
authors.lastname: Ellor
mesh_terms: D000383:Agriculture; D008670:Metals / Q000032:analysis; D004364:Pharmaceutical Preparations / Q000032:analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis; D012722:Sewage / Q000032:analysis*; D012987:Soil / Q000737:chemistry; D006113:United Kingdom; D062065:Wastewater / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D008670:Metals; D004364:Pharmaceutical Preparations; D011084:Polycyclic Aromatic Hydrocarbons; D012722:Sewage; D012987:Soil; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Chemical Investigations Programme; Priority substances; Sewage Sludge Directive; Sludge; Trace substances