title: Is anaerobic digestion effective for the removal of organic micropollutants and biological activities from sewage sludge?
abstract: The occurrence of emerging organic micropollutants (OMPs) in sewage sludge has been widely reported; nevertheless, their fate during sludge treatment remains unclear. The objective of this work was to study the fate of OMPs during mesophilic and thermophilic anaerobic digestion (AD), the most common processes used for sludge stabilization, by using raw sewage sludge without spiking OMPs. Moreover, the results of analytical chemistry were complemented with biological assays in order to verify the possible adverse effects (estrogenic and genotoxic) on the environment and human health in view of an agricultural (re)use of digested sludge. Musk fragrances (AHTN, HHCB), ibuprofen (IBP) and triclosan (TCS) were the most abundant compounds detected in sewage sludge. In general, the efficiency of the AD process was not dependent on operational parameters but compound-specific: some OMPs were highly biotransformed (e.g. sulfamethoxazole and naproxen), while others were only slightly affected (e.g. IBP and TCS) or even unaltered (e.g. AHTN and HHCB). The MCF-7 assay evidenced that estrogenicity removal was driven by temperature. The Ames test did not show point mutation in Salmonella typhimurium while the Comet test exhibited a genotoxic effect on human leukocytes attenuated by AD. This study highlights the importance of combining chemical analysis and biological activities in order to establish appropriate operational strategies for a safer disposal of sewage sludge. Actually, it was demonstrated that temperature has an insignificant effect on the disappearance of the parent compounds while it is crucial to decrease estrogenicity.
authors.affiliation: Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, Rúa Lope Gómez de Marzoa, E-15782 Santiago de Compostela, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Gonzalez-Gil
authors.affiliation: Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, Rúa Lope Gómez de Marzoa, E-15782 Santiago de Compostela, Spain; Department of Civil, Environmental, Architectural Engineering and Mathematics, University of Brescia, via Branze 43, I-25123 Brescia, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Papa
authors.affiliation: Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, Viale Europa 11, I-25123 Brescia, Italy; Brescia University Research Center "Integrated Models for Prevention and Protection in Environmental and Occupational Health" (MISTRAL), Italy.
authors.forename: D
authors.initials: D
authors.lastname: Feretti
authors.affiliation: Department of Medical and Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, Viale Europa 11, I-25123 Brescia, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Ceretti
authors.affiliation: Department of Clinical & Experimental Sciences, University of Brescia, viale Europa 11, I-25123 Brescia, Italy; Brescia University Research Center "Integrated Models for Prevention and Protection in Environmental and Occupational Health" (MISTRAL), Italy.
authors.forename: G
authors.initials: G
authors.lastname: Mazzoleni
authors.affiliation: Department of Clinical & Experimental Sciences, University of Brescia, viale Europa 11, I-25123 Brescia, Italy.
authors.forename: N
authors.initials: N
authors.lastname: Steimberg
authors.affiliation: Department of Mechanical and Industrial Engineering, University of Brescia, via Branze 38, I-25123 Brescia, Italy; Brescia University Research Center "Integrated Models for Prevention and Protection in Environmental and Occupational Health" (MISTRAL), Italy.
authors.forename: R
authors.initials: R
authors.lastname: Pedrazzani
authors.affiliation: Department of Civil, Environmental, Architectural Engineering and Mathematics, University of Brescia, via Branze 43, I-25123 Brescia, Italy; Brescia University Research Center "Integrated Models for Prevention and Protection in Environmental and Occupational Health" (MISTRAL), Italy.
authors.forename: G
authors.initials: G
authors.lastname: Bertanza
authors.affiliation: Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, Rúa Lope Gómez de Marzoa, E-15782 Santiago de Compostela, Spain.
authors.forename: J M
authors.initials: JM
authors.lastname: Lema
authors.affiliation: Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, Rúa Lope Gómez de Marzoa, E-15782 Santiago de Compostela, Spain. Electronic address: marta.carballa@usc.es.
authors.forename: M
authors.initials: M
authors.lastname: Carballa
mesh_terms: D000693:Anaerobiosis; D006801:Humans; D010476:Perfume; D012722:Sewage / Q000737:chemistry*; D013420:Sulfamethoxazole; D013696:Temperature; D014865:Waste Disposal, Fluid
chemical_list: D010476:Perfume; D012722:Sewage; D013420:Sulfamethoxazole
keywords: Estrogenicity; Genotoxicity; Mesophilic digestion; Organic micropollutants; Sewage sludge; Thermophilic digestion