Journal Article

Detection of the Marijuana Metabolite 11-Nor-Δ<sup>9</sup>-Tetrahydrocannabinol-9-Carboxylic Acid in Oral Fluid Specimens and Its Contribution to Positive Results in Screening Assays

Christine Moore, Wayne Ross, Cynthia Coulter, Laura Adams, Sumandeep Rana, Michael Vincent and James Soares

in Journal of Analytical Toxicology

Volume 30, issue 7, pages 413-418
Published in print September 2006 | ISSN: 0146-4760
Published online September 2006 | e-ISSN: 1945-2403 | DOI:
Detection of the Marijuana Metabolite 11-Nor-Δ9-Tetrahydrocannabinol-9-Carboxylic Acid in Oral Fluid Specimens and Its Contribution to Positive Results in Screening Assays

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The detection of the marijuana metabolite 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in oral fluid specimens is described, and its contribution to an immunoassay for the detection of cannabinoids is investigated. Oral fluid specimens, screened using an enzyme-linked immunosorbent immunoassay (ELISA), were carried forward to confirmation for both tetrahydrocannabinol (THC) and THC-COOH using gas chromatography-mass spectrometry (GC-MS). One hundred and fifty-three specimens were analyzed, of which 143 screened positive for cannabinoids. Ninety-five (66.4%) of these specimens were positive for both THC and THC-COOH; 14 (9.7%) were positive for THC-COOH only, and 27 (18.8%) were positive for THC only. The GC-MS assay for the detection of THC-COOH in oral fluid was linear to 160 pg/mL with a limit of quantitation of 2 pg/mL. The detection of the marijuana metabolite, THC-COOH, in 76.2% of oral fluid specimens screening positive for cannabinoids is reported. As a potential defense against passive exposure claims, proposed SAMHSA regulations may require the simultaneous collection of a urine sample when oral fluid samples are used. The detection of the metabolite, THC-COOH, is a significant alternative to this approach because its presence in oral fluid minimizes the argument for passive exposure to marijuana in drug testing cases.

Journal Article.  0 words. 

Subjects: Medical Toxicology ; Toxicology (Non-medical)

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