We report a streamlined procedure for the routine analysis of cocaine in municipal wastewater. By adding NaOH (to 0.025 M) and incubating wastewater samples at 55 °C for two hours, cocaine and its principal metabolites are quantitatively converted into three products, ecgonine, anhydroecgonine, and norecgonine. Ecgonine, the principal hydrolysis end-product, can be directly determined (without pre-concentration) by liquid chromatography-tandem mass spectrometry (LC/MS/MS) using either reverse phase (RP) or hydrophilic interaction (HILIC) chromatography. In addition to cocaine, three opioids (morphine, hydrocodone, and oxycodone), five phenylamine drugs (amphetamine, methamphetamine, MDMA, MBDB, and MDEA), and two human use markers (cotinine and creatinine) can also be analyzed, as they are stable to hydrolysis. Results obtained by applying the streamlined approach for the analysis of drugs of abuse in untreated municipal wastewater are in excellent agreement with those obtained from the more comprehensive (SPE-)RPLC/MS/MS method described in our companion paper. Seven analytes (ecgonine methyl ester, ecgonine ethyl ester, anhydroecgonine methyl ester, m-hydroxybenzoylecgonine, p-hydroxybenzoylecgonine, ecgonine, and anhydroecgonine) were detected for the first time in an environmental sample.
Citation: Environmental Science & Technology
Pub Type: Journals
liquid chromatography, mass spectrometry, illicit drugs, wastewater, solid phase extraction, metabolites, hydrolysis, hydrophilic interaction chromatography (HILIC)