Analysis of drugs of abuse by online SPE-LC high resolution mass spectrometry: Communal assessment of consumption

An online SPE-LC-HRMS method was developed to monitor the consumption of 18 drugs of abuse (DOAs) including amphetamines, opioids, cocainics, cannabinoids, lysergics, and their corresponding metabolites in a well characterized college campus setting via wastewater analysis. Filtered and diluted (10 x) sewage water samples (5 mL inj) were automatically pre-concentrated and analyzed in 15 min using a Thermo EQuan MAX online SPE system equipped with a HyperSep (TM) Retain PEP (20 x 2.1 mm x 12 mu m) SPE column and a Hypersil Gold (TM) aQ (150 x 2.1 mm x 3 mu m) analytical column. A Q Exactive (TM) Hybrid Quadrupole-Orbitrap FIRMS was used in full scan mode (R = 140,000) for positive identification, and quantitation of target compounds. Method detection limits for all analytes ranged between 0.6 and 1.7 ng/L in sewage. A total of 14 DOAs were detected from two different locations (dorms and main college campus) within a one-year period. Most frequently detected drugs throughout the entire study were amphetamine (>96%) and THC's metabolite 11-nor-9-carboxy-Delta-9-THC (>100%) with maximum concentrations of 5956 and 2413 ng/L respectively. Daily doses per 1000 people were determined in order to assess consumption of THC, amphetamine, heroin and cocaine, in both dorms and main campus. (C) 2014 Elsevier B.V. All rights reserved.