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NCJ Number: 222201 Find in a Library
Title: Excretion of Delta9-Tetrahydrocannabinol in Sweat
Journal: Forensic Science International  Volume:174  Issue:2-3  Dated:January 2008  Pages:173-177
Author(s): Marilyn A. Huestis; Karl B. Scheidweiler; Takeshi Saito; Neil Fortner; Tsadik Abraham; Richard A. Gustafson; Michael L. Smith
Date Published: January 2008
Page Count: 5
Sponsoring Agency: American Registry of Pathology
Washington, DC 20306-6000
National Institute on Drug Abuse
Bethesda, MD 20892-9561
National Institutes of Health
Bethesda, MD 20014
Type: Report (Study/Research)
Format: Article
Language: English
Country: United States of America
Annotation: This clinical study examined the level of THC (delta9-tetrahydrocannabinol) excreted in the sweat of 11 daily cannabis users after cessation of drug use.
Abstract: Sweat patches worn by daily cannabis users the first week of monitored abstinence had THC concentrations that averaged 3.85 ng/patch. Eight of the 11 subjects had negative second-week patches, using the cutoff concentration of 1 ng THC/patch (cutoff set by U.S. Substance Abuse Mental Health Services Administration for Federal workplace testing). One subject was still positive 4 weeks after ceasing drug use. Subjects who took THC orally up to 14.8 mg daily, either intentionally or unknowingly, did not produce a positive sweat patch at a cutoff concentration of 0.4 ng THC/patch. The advantage of sweat testing is that it is not subject to the periodic fluctuations in concentration found in sequential urine specimens, which makes identifying new drug use more difficult. Also, a single sweat patch analysis provides a summary of drug use or drug washout for the previous week. Multiple urine collections and analyses would be required to cover the same period. The sensitivity of sweat patches in detecting new drug use following cannabis smoking is not known. This requires an independent controlled smoked cannabis administration study. All study participants resided in the secure clinical research unit of the Intramural Research program, National Institute on Drug abuse, National Institutes of Health, Baltimore, MD, while participating in the clinical studies. 2 tables, 1 figure, and 27 references
Main Term(s): Criminology; United States of America
Index Term(s): Blood/body fluid analysis; Drug analysis; Drug testing; Investigative techniques; Marijuana
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