skip navigation


Register for Latest Research

Stay Informed
Register with NCJRS to receive NCJRS's biweekly e-newsletter JUSTINFO and additional periodic emails from NCJRS and the NCJRS federal sponsors that highlight the latest research published or sponsored by the Office of Justice Programs.

NCJRS Abstract

The document referenced below is part of the NCJRS Virtual Library collection. To conduct further searches of the collection, visit the Virtual Library. See the Obtain Documents page for direction on how to access resources online, via mail, through interlibrary loans, or in a local library.


NCJ Number: 163138 Find in a Library
Title: Window for Marijuana Detection Called Shorter Than Assumed
Journal: Drug Detection Report  Volume:5  Issue:14  Dated:(October 20, 1995)  Pages:1-3
Editor(s): V Taylor
Date Published: 1995
Page Count: 3
Type: Report (Technical)
Format: Article
Language: English
Country: United States of America
Annotation: This article discusses research indicating that urine tests for marijuana yield positive results for a shorter time period following marijuana use than has commonly been assumed.
Abstract: It has commonly been assumed that a urine test for marijuana use can yield a positive result for a week or longer. Recent research showed that, when the Federal Government's cutoff level for a positive test is used, the time period for detection after use, the window of detection, can be less than 2 days for an individual who smoked one marijuana cigarette. Researchers tested more than 1,000 urine specimens from six male subjects over a three-week period. A computer was used to standardize the number of puffs each subject took on a marijuana cigarette, time between puffs, the amount of time the smoke was inhaled, and the amount of time it was held in; there was no control for the depth of inhalation. Each subject had specimens tested on seven different immunoassays at different cutoff levels. Results were also obtained from tests on the gas chromatography/mass spectrometry drug testing system.
Main Term(s): Controlled Substances
Index Term(s): Chromatography; Computers; Drug analysis; Drug detection; Drug research; Drug testing; Drug use; Evidence identification; Forensic medicine; Marijuana; Mass spectroscopy; Urinalysis
To cite this abstract, use the following link:

*A link to the full-text document is provided whenever possible. For documents not available online, a link to the publisher's website is provided. Tell us how you use the NCJRS Library and Abstracts Database - send us your feedback.