Studies Examine Effects of Marijuana on Driving
The National Highway Traffic Safety Administration (NHTSA) and the National Institute on Drug Abuse (NIDA) are wrapping up their three-year study investigating how smoking marijuana affects a person’s ability to drive, as Matt Schmitz and Chris Woodyard write in an article appearing on USA Today. The writers note that in Colorado, there has been an increase in driving deaths in which marijuana was involved, beginning in 2009, the year the state legalized medical marijuana. “As more states are poised to legalize medicinal marijuana, it’s looking like dope is playing a larger role as a cause of fatal traffic accidents,” Schmitz and Woodyard write.
The increase in Colorado driving fatalities among those who smoked marijuana was found in a new study funded by NIDA and the National Institute on Alcohol Abuse and Alcoholism (NIAAA), according to a NIDA press release. The study, called “Trends in fatal motor vehicle crashes before and after marijuana commercialization in Colorado,” did not find a similar increase in the 34 states that did not have medical marijuana laws when the study was conducted, NIDA writes. However, during that same time period, there was no change in the number of fatal crashes among alcohol-impaired drivers in either Colorado or the 34 states that did not allow medical marijuana during the time period of the study, NIDA writes. The study concludes that Colorado needs to change its policies to focus on preventing stoned driving, including a campaign to educate the population about the risks of driving under the influence of marijuana.
USA Today writes that marijuana contributed to 12% of traffic deaths in the U.S. in 2010, three times the number of such deaths that occurred a decade earlier, according to a Columbia University study. In that study, researchers did a toxicology examination of 24,000 driving fatalities, USA Today reports.
The NHTSA/NIDA study, which is in its final months, uses what NHTSA calls “the world’s most advanced driving simulator,” USA Today reports. The simulator, created by the University of Iowa, was previously used to study the effects of alcohol on driving. USA Today writes:
Tests observe participants who ingest a low dose of THC, the active ingredient in marijuana, a high dose and a placebo to assess the effects on performance, decision-making, motor control, risk-taking behavior and divided-attention tasks.
In a related news item, Donald W. Meyers writes for Washington’s Yakima Herald-Republic that the Washington Traffic Safety Commission (WTSC) is facilitating a survey on the effects of THC (marijuana’s active ingredient) on driving, for the NHTSA. Washington’s first recreational marijuana stores could open as early as next month. (In Colorado, the first state to allow recreational marijuana, the sale of recreational pot became legal on January 1 of this year.) The Washington survey pays drivers $60 to answer questions and provide blood and saliva samples to be tested for the presence of THC, Meyers writes.
Shelly Baldwin, a program manager for WTSC, told Meyers that the results of the Washington survey will be used to draft policies and would also provide information on the effects of various THC levels on driving. Survey participants who agreed to answer questions but refused to give blood samples were paid $10. The survey, in which participants are anonymous, will also be conducted in other parts of Washington besides Yakima, including Spokane, King, Snohomish, Whatcom, and Kitsap, Meyers writes.