Simultaneous determination of traditional and emerging illicit drugs in sediments, sludges and particulate matter

An analytical method for determining traditional and emerging drugs of abuse in particulate matter, sewage sludge and sediment has been developed and validated. A total of 41 drugs of abuse and metabolites including cocainics, tryptamines, amphetamines, arylcyclohexylamines, cathinones, morphine derivatives, pyrrolidifenones derivatives, entactogens, piperazines and other psychostimulants were selected. Samples were ultrasound extracted with McIlvaine buffer and methanol, and the extracts were cleaned up by solid phase extraction (SPE) using Strata-X cartridges. Drugs were eluted using methanol and methanol-dichloromethane and determined by liquid chromatography tandem mass spectrometry. The optimum solid-liquid extraction (SLE) conditions were: weight 1g of sample and ultrasound assisted extraction (UAE) with 10mL of methanol-McIlvain buffer (1:1, v/v, pH 4.5) for 10min. Recoveries for all compounds were ≥50% in the three matrices with the exception of ephedrine (EPHE), 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), ecgonine methyester (ECME), heroin (HER), 3,4-methylendioxyamphetamine (MDA) and 4-acetoxy N,N'-dimethyltryptamine (4-AcO-DIPT) and methadone (MET). Data acquisition was done by selective reaction monitoring (SRM), and the two most abundant product ions were used for confirmation. Limits of detection were lower than 1.32ngg-1 dry weight (d.w.) and limits of quantification were between 0.12 and 3.96ngg-1 (d.w.). The method was applied to the analysis of particulate matter, where cocaine (COC), benzoylecgonine (BECG), ecgoninemethylester (ECME), cocaethylene (COCET), methadone (MET) and codeine (COD) were mostly detected. In the case of dehydrated sludge, opioids are at higher concentration than cocainics and some emerging drugs such as 4-methoxyamphetamine (PMA), ketamine (KET) and bufotenine (BUF) were detected. In sediment COC, 4-methoxyphencyclidine (4-MeO-PCP), MET and BECG were most relevant compounds. © 2015 Elsevier B.V.This work has been supported by the Spanish Ministry of Economy and Competitiveness through the projects (GCL2011-29703-C02-02). M. Jesús Andrés-Costa also thanks the Spanish Ministry for the FPI grant.Peer Reviewe