TY - JOUR

T1 - Investigation of biotransformation products of p-methoxymethylamphetamine and dihydromephedrone in wastewater by high-resolution mass spectrometry

AU - Kinyua, Juliet

AU - Psoma, Aikaterini K.

AU - Rousis, Nikolaos I.

AU - Nika, Maria Christina

AU - Covaci, Adrian

AU - Van Nuijs, Alexander L.N.

AU - Τhomaidis, Νikolaos S.

N1 - Funding Information: Acknowledgments: We would like to thank the staff at Toxicological Center (University of Antwerp), National and Kapodistrian University of Athens (Trace Analysis Mass Spectrometry group, TrAMS), Philanthropic Educational Organization (PEO) and American Association of University Women (AAUW) for their support. This work was supported by the COST Action ES1307 “SCORE–Sewage biomarker analysis for community health assessment”. Funding Information: Funding: Juliet Kinyua acknowledges the “Sewage Analysis CORe group Europe (SCORE)” for her Short-Term Scientific Mission (STSM) grant and the EU International Training Network SEWPROF (Marie Curie-Grant number 317205) for her PhD fellowship. The APC was funded by the Special Account for Research Grants of NKUA (Grant # 7737). Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

PY - 2021

Y1 - 2021

N2 - There is a paucity of information on biotransformation and stability of new psychoactive substances (NPS) in wastewater. Moreover, the fate of NPS and their transformation products (TPs) in wastewater treatment plants is not well understood. In this study, batch reactors seeded with activated sludge were set up to evaluate biotic, abiotic, and sorption losses of p-methoxymethylamphetamine (PMMA) and dihydromephedrone (DHM) and identify TPs formed during these processes. Detection and identification of all compounds was performed with target and suspect screening approaches using liquid chromatography quadrupole-time-of-flight mass spectrometry. Influent and effluent 24 h composite wastewater samples were collected from Athens from 2014 to 2020. High elimination rates were found for PMMA (80%) and DHM (97%) after a seven-day experiment and degradation appeared to be related to biological activity in the active bioreactor. Ten TPs were identified and the main reactions were O- and N-demethylation, oxidation, and hydroxylation. Some TPs were reported for the first time and some were confirmed by reference standards. Identification of some TPs was enhanced by the use of an in-house retention time prediction model. Mephedrone and some of its previously reported human metabolites were formed from DHM incubation. Retrospective analysis showed that PMMA was the most frequently detected compound.

AB - There is a paucity of information on biotransformation and stability of new psychoactive substances (NPS) in wastewater. Moreover, the fate of NPS and their transformation products (TPs) in wastewater treatment plants is not well understood. In this study, batch reactors seeded with activated sludge were set up to evaluate biotic, abiotic, and sorption losses of p-methoxymethylamphetamine (PMMA) and dihydromephedrone (DHM) and identify TPs formed during these processes. Detection and identification of all compounds was performed with target and suspect screening approaches using liquid chromatography quadrupole-time-of-flight mass spectrometry. Influent and effluent 24 h composite wastewater samples were collected from Athens from 2014 to 2020. High elimination rates were found for PMMA (80%) and DHM (97%) after a seven-day experiment and degradation appeared to be related to biological activity in the active bioreactor. Ten TPs were identified and the main reactions were O- and N-demethylation, oxidation, and hydroxylation. Some TPs were reported for the first time and some were confirmed by reference standards. Identification of some TPs was enhanced by the use of an in-house retention time prediction model. Mephedrone and some of its previously reported human metabolites were formed from DHM incubation. Retrospective analysis showed that PMMA was the most frequently detected compound.

KW - Activated sludge

KW - Liquid chromatography tandem mass spectrometry

KW - Mephedrone

KW - New psychoactive substances

KW - Retention time prediction model

KW - Target and suspect screening

KW - Transformation products

KW - Wastewater-based epidemiology

U2 - 10.3390/metabo11020066

DO - 10.3390/metabo11020066

M3 - Journal article

C2 - 33503865

AN - SCOPUS:85100751540

VL - 11

JO - Metabolites

JF - Metabolites

SN - 2218-1989

IS - 2

M1 - 66

ER -