title: Pharmaceutically active compounds in sludge stabilization treatments: anaerobic and aerobic digestion, wastewater stabilization ponds and composting.
abstract: Sewage sludge disposal onto lands has been stabilized previously but still many pollutants are not efficiently removed. Special interest has been focused on pharmaceutical compounds due to their potential ecotoxicological effects. Nowadays, there is scarce information about their occurrence in different sludge stabilization treatments. In this work, the occurrence of twenty-two pharmaceutically active compounds has been studied in sludge from four sludge stabilization treatments: anaerobic digestion, aerobic digestion, composting and lagooning. The types of sludge evaluated were primary, secondary, anaerobically-digested and dehydrated, composted, mixed, aerobically-digested and dehydrated and lagoon sludge. Nineteen of the twenty-two pharmaceutically active compounds monitored were detected in sewage sludge. The most contaminated samples were primary sludge, secondary sludge and mixed sludge (the average concentrations of studied compounds in these sludges were 179, 310 and 142 μg/kg dm, respectively) while the mean concentrations found in the other types of sewage sludge were 70 μg/kg dm (aerobically-digested sludge), 63 μg/kg dm (lagoon sludge), 12 μg/kg dm (composted sludge) and 8 μg/kg dm (anaerobically-digested sludge). The antibiotics ciprofloxacin and norfloxacin were found at the highest concentration levels in most of the analyzed sludge samples (up to 2660 and 4328 μg/kg dm, respectively). Anaerobic-digestion treatment reduced more considerably the concentration of most of the studied compounds than aerobic-digestion (especially in the case of bezafibrate and fluoroquinolones) and more than anaerobic stabilization ponds (in the case of acetaminophen, atenolol, bezafibrate, carbamazepine, 17α-ethinylestradiol, naproxen and salicylic acid). Ecotoxicological risk assessment, of sludge application onto soils, has also been evaluated. Risk quotients, expressed as the ratio between the predicted environmental concentration and the predicted non-effect concentration, were lower than 1 for all the pharmaceutically active compounds so no significant risks are expected to occur due to the application of sewage sludge onto soils, except for 17α-ethinylestradiol when chronic toxicity was considered.
authors.affiliation: Department of Analytical Chemistry, Escuela Politécnica Superior, University of Seville, C/Virgen de África 7, E-41011 Seville, Spain.
authors.forename: Julia
authors.initials: J
authors.lastname: Martín
authors.affiliation: Department of Analytical Chemistry, Escuela Politécnica Superior, University of Seville, C/Virgen de África 7, E-41011 Seville, Spain. Electronic address: jlsantos@us.es.
authors.forename: Juan Luis
authors.initials: JL
authors.lastname: Santos
authors.affiliation: Department of Analytical Chemistry, Escuela Politécnica Superior, University of Seville, C/Virgen de África 7, E-41011 Seville, Spain.
authors.forename: Irene
authors.initials: I
authors.lastname: Aparicio
authors.affiliation: Department of Analytical Chemistry, Escuela Politécnica Superior, University of Seville, C/Virgen de África 7, E-41011 Seville, Spain.
authors.forename: Esteban
authors.initials: E
authors.lastname: Alonso
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D004364:Pharmaceutical Preparations / Q000032:analysis* / Q000378:metabolism; D061005:Ponds / Q000737:chemistry / Q000382:microbiology; D018570:Risk Assessment; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry* / Q000382:microbiology; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism
chemical_list: D004364:Pharmaceutical Preparations; D012722:Sewage; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Aerobic treatment; Anaerobic treatment; Pharmaceutically active compounds; Risk assessment; Sewage sludge; Treatment processes