title: The stability of illicit drugs and metabolites in wastewater, an important issue for sewage epidemiology?
abstract: The stability of nine illicit drugs and metabolites in influent wastewater at relevant conditions (20 °C and at pH 7.5) was evaluated during 26 h (in 1 h intervals) to assess whether significant in-sewer processes of degradation or formation occur. This assessment is important for the sewage epidemiology approach, which uses concentrations of illicit drugs and metabolites in influent wastewater to back-calculate amounts of these substances used by a community or population. The results of this study showed that amphetamine, methamphetamine, ecstasy and EDDP (metabolite of methadone) are stable in wastewater for 12 h and longer. For benzoylecgonine and methadone, a modest formation in the course of time was observed (0.2% per h and 0.4% per h, respectively), while for cocaine (40% degradation after 12 h), ecgonine methylester (20% degradation after 12 h), and 6-monoacetylmorphine (20% degradation after 12 h), a clear decrease in concentrations in time was seen. These findings suggest that for compounds with a significant stability issue, it is important to take their behavior into account when performing back-calculations in sewage epidemiology. However, this study also highlights the need of future research regarding transformation pathways of the individual compounds.
authors.affiliation: Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp (UA), University Hospital of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium.
authors.forename: Alexander L N
authors.initials: AL
authors.lastname: van Nuijs
authors.forename: Karim
authors.initials: K
authors.lastname: Abdellati
authors.forename: Lieven
authors.initials: L
authors.lastname: Bervoets
authors.forename: Ronny
authors.initials: R
authors.lastname: Blust
authors.forename: Philippe G
authors.initials: PG
authors.lastname: Jorens
authors.forename: Hugo
authors.initials: H
authors.lastname: Neels
authors.forename: Adrian
authors.initials: A
authors.lastname: Covaci
mesh_terms: D004784:Environmental Monitoring; D006863:Hydrogen-Ion Concentration; D013287:Illicit Drugs / Q000032:analysis* / Q000737:chemistry; D012722:Sewage / Q000032:analysis*; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry
chemical_list: D013287:Illicit Drugs; D012722:Sewage; D014874:Water Pollutants, Chemical