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Bluelight Crew
For the 20 states in which marijuana is legal, either for medicinal or recreational purposes, there’s a new challenge for law enforcement: judging whether stoned users are too impaired to drive.
On any given Friday and Saturday night in California, 7% of drivers on the road test positive for marijuana, according to the state’s first comprehensive roadside survey of alcohol and drug use while driving, conducted by the Pacific Institute for Research and Evaluation for the state’s highway department. That percentage is similar to the proportion of drivers who recorded some alcohol (not necessarily exceeding the legal limit for driving under the influence) in their blood.
While the survey does not address whether the positive tests resulted in impaired driving — more than 1,300 drivers were randomly pulled over and asked if they would participate in the study without any legal consequences resulting from the alcohol and drug testing — the study may help law enforcement officials to better understand how legalizing marijuana will impact driving decisions. Eighteen states, including California, currently allow marijuana for medical use, and Colorado and Washington became the first states to legalize recreational use — potentially creating a larger pool of stoned drivers.
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The question of whether the people who test positive for marijuana are actually affected by the drug at the time they are driving, however, remains difficult to answer. The study used a cutoff level of 2 nanograms per milliliter of saliva of THC, the main psychoactive ingredient in marijuana. Driving within three hours of smoking pot is associated with a near doubling of the risk of fatal crashes. However, THC can remain in blood and saliva for highly variable times after the last use of the drug. Although the marijuana “high” only lasts three to five hours, studies of heavy users in a locked hospital ward showed THC can be detected in the blood up to a week after they are abstinent, and the outer limit of detection time in saliva tests is not known. While marijuana does not promote uninhibited and potentially reckless behavior like alcohol does, THC does have mild hallocinogenic and sedative effects, and studies show it can impair cognition and memory, making driving potentially more hazardous.
Read more: http://healthland.time.com/2012/11/...arijuana-but-are-they-impaired/#ixzz2D3vIWxMd
On any given Friday and Saturday night in California, 7% of drivers on the road test positive for marijuana, according to the state’s first comprehensive roadside survey of alcohol and drug use while driving, conducted by the Pacific Institute for Research and Evaluation for the state’s highway department. That percentage is similar to the proportion of drivers who recorded some alcohol (not necessarily exceeding the legal limit for driving under the influence) in their blood.
While the survey does not address whether the positive tests resulted in impaired driving — more than 1,300 drivers were randomly pulled over and asked if they would participate in the study without any legal consequences resulting from the alcohol and drug testing — the study may help law enforcement officials to better understand how legalizing marijuana will impact driving decisions. Eighteen states, including California, currently allow marijuana for medical use, and Colorado and Washington became the first states to legalize recreational use — potentially creating a larger pool of stoned drivers.
. . .
The question of whether the people who test positive for marijuana are actually affected by the drug at the time they are driving, however, remains difficult to answer. The study used a cutoff level of 2 nanograms per milliliter of saliva of THC, the main psychoactive ingredient in marijuana. Driving within three hours of smoking pot is associated with a near doubling of the risk of fatal crashes. However, THC can remain in blood and saliva for highly variable times after the last use of the drug. Although the marijuana “high” only lasts three to five hours, studies of heavy users in a locked hospital ward showed THC can be detected in the blood up to a week after they are abstinent, and the outer limit of detection time in saliva tests is not known. While marijuana does not promote uninhibited and potentially reckless behavior like alcohol does, THC does have mild hallocinogenic and sedative effects, and studies show it can impair cognition and memory, making driving potentially more hazardous.
Read more: http://healthland.time.com/2012/11/...arijuana-but-are-they-impaired/#ixzz2D3vIWxMd
