Investigation of cannabis biomarkers and transformation products in waters by liquid chromatography coupled to time of flight and triple quadrupole mass spectrometry.
11-Nor-9-carboxy-Δ(9)-tetrahydrocannabinol (THC-COOH) is commonly selected as biomarker for the investigation of cannabis consumption through wastewater analysis. The removal efficiency of THC-COOH in wastewater treatment plants (WWTPs) has been reported to vary between 31% and 98%. Accordingly, possible transformation products (TPs) of this metabolite might be formed during treatment processes or in receiving surface water under environmental conditions. In this work, surface water was spiked with THC-COOH and subjected to hydrolysis, chlorination and photo-degradation (both ultraviolet and simulated sunlight) experiments under laboratory-controlled conditions. One hydrolysis, eight chlorination, three ultraviolet photo-degradation and seven sunlight photo-degradation TPs were tentatively identified by liquid chromatography coupled to quadrupole time-of-flight mass spectrometer (LC-QTOF MS). In a subsequent step, THC-COOH and the identified TPs were searched in wastewater samples using LC coupled to tandem mass spectrometry (LC-MS/MS) with triple quadrupole. THC-COOH was found in all influent and effluent wastewater samples analyzed, although at significant lower concentrations in the effluent samples. The removal efficiency of WWTP under study was approximately 86%. Furthermore, THC-COOH was also investigated in several surface waters, and it was detected in 50% of the samples analyzed. Regarding TPs, none were found in influent wastewater, while one hydrolysis and five photo-degradation (simulated sunlight) TPs were detected in effluent and surface waters. The most detected compound, resulting from sunlight photo-degradation, was found in 60% of surface waters analyzed. This fact illustrates the importance of investigating these TPs in the aquatic environment.
Research Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat, E-12071 Castellón, Spain.
Clara
C
Boix
Research Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat, E-12071 Castellón, Spain.
María
M
Ibáñez
Research Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat, E-12071 Castellón, Spain.
Lubertus
L
Bijlsma
Research Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat, E-12071 Castellón, Spain.
Juan V
JV
Sancho
Research Institute for Pesticides and Water, University Jaume I, Avda. Sos Baynat, E-12071 Castellón, Spain. Electronic address: felix.hernandez@uji.es.
Félix
F
Hernández
D015415:Biomarkers / Q000032:analysis*; D002188:Cannabis; D002853:Chromatography, Liquid / Q000379:methods; D013759:Dronabinol / Q000031:analogs & derivatives* / Q000032:analysis; D004784:Environmental Monitoring / Q000379:methods; D013287:Illicit Drugs / Q000032:analysis; D015813:Substance Abuse Detection / Q000379:methods; D019966:Substance-Related Disorders / Q000453:epidemiology; D053719:Tandem Mass Spectrometry / Q000379:methods; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*
D015415:Biomarkers; D013759:Dronabinol; D013287:Illicit Drugs; D062065:Wastewater; D014874:Water Pollutants, Chemical; C016780:11-nor-delta(9)-tetrahydrocannabinol-9-carboxylic acid
Cannabis biomarkers; Removal efficiency; Surface water; Time-of-flight mass spectrometry; Transformation/degradation products; Wastewater