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NIDA. (2013, November 21). New breath test may detect recent marijuana use. Retrieved from

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Science Spotlight

November 21, 2013

Car crash

Marijuana causes serious impairment in motor skills, judgment, and perception, which are necessary for operating a vehicle safely. In the past, testing drivers for recent marijuana use has not been as simple as testing for alcohol, but preliminary research on the detection of THC – the main psychoactive chemical in marijuana - in the breath of marijuana smokers may change that. According to NIDA scientists who published their work in September, a new breath test they have developed can in most cases detect whether a person used marijuana within the previous ½ hour to 2.5 hours, depending on the frequency of use. This could be a valuable tool for workplace or roadside marijuana testing.

For a copy of the article (published online September 17), go to Issues Related to the Study of Cannabinoids in Exhaled Breath. For facts on drugged driving, go to

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