title: Sewage-based epidemiology in monitoring the use of new psychoactive substances: Validation and application of an analytical method using LC-MS/MS.
abstract: Sewage-based epidemiology (SBE) employs the analysis of sewage to detect and quantify drug use within a community. While SBE has been applied repeatedly for the estimation of classical illicit drugs, only few studies investigated new psychoactive substances (NPS). These compounds mimic effects of illicit drugs by introducing slight modifications to chemical structures of controlled illicit drugs. We describe the optimization, validation, and application of an analytical method using liquid chromatography coupled to positive electrospray tandem mass spectrometry (LC-ESI-MS/MS) for the determination of seven NPS in sewage: methoxetamine (MXE), butylone, ethylone, methylone, methiopropamine (MPA), 4-methoxymethamphetamine (PMMA), and 4-methoxyamphetamine (PMA). Sample preparation was performed using solid-phase extraction (SPE) with Oasis MCX cartridges. The LC separation was done with a HILIC (150 x 3 mm, 5 µm) column which ensured good resolution of the analytes with a total run time of 19 min. The lower limit of quantification (LLOQ) was between 0.5 and 5 ng/L for all compounds. The method was validated by evaluating the following parameters: sensitivity, selectivity, linearity, accuracy, precision, recoveries and matrix effects. The method was applied on sewage samples collected from sewage treatment plants in Belgium and Switzerland in which all investigated compounds were detected, except MPA and PMA. Furthermore, a consistent presence of MXE has been observed in most of the sewage samples at levels higher than LLOQ.
authors: Toxicological Center, Department of Pharmaceutical Sciences, Campus Drie Eiken, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium.
authors: Juliet
authors: J
authors: Kinyua
authors: Toxicological Center, Department of Pharmaceutical Sciences, Campus Drie Eiken, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium.
authors: Adrian
authors: A
authors: Covaci
authors: Toxicological Center, Department of Pharmaceutical Sciences, Campus Drie Eiken, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium.
authors: Walid
authors: W
authors: Maho
authors: Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600, Dübendorf, Switzerland.
authors: Ann-Kathrin
authors: AK
authors: McCall
authors: Toxicological Center, Department of Pharmaceutical Sciences, Campus Drie Eiken, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium.
authors: Hugo
authors: H
authors: Neels
authors: Toxicological Center, Department of Pharmaceutical Sciences, Campus Drie Eiken, University of Antwerp, Universiteitsplein 1, 2610, Antwerp, Belgium.
authors: Alexander L N
authors: AL
authors: van Nuijs
mesh_terms: D001530:Belgium; D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D013287:Illicit Drugs / Q000032:analysis*; D057230:Limit of Detection; D011619:Psychotropic Drugs / Q000032:analysis*; D015203:Reproducibility of Results; D012722:Sewage / Q000032:analysis*; D052616:Solid Phase Extraction / Q000379:methods; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D013557:Switzerland; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D013287:Illicit Drugs; D011619:Psychotropic Drugs; D012722:Sewage; D014874:Water Pollutants, Chemical
keywords: LC-MS/MS; methoxetamine; novel psychoactive substances (NPS); sewage epidemiology; wastewater