askites (shot in Downtown Denver, Colorado)
The photographer writes: “I was shooting clouds, and these guys started mugging for the camera between joint puffs. I couldn’t resist.”

A new study says that people driving while high on marijuana are almost three times as likely to wind up in an accident. In the study, published recently by the journal Epidemiologic Reviews, researchers analyzed information from nine studies done in six other countries on marijuana use and motor vehicle accidents. The study’s authors found that marijuana use within three hours of driving increases a driver’s risk of an accident by 2.7 times, and the more pot a driver smokes (and the more often), the greater the chance that he or she will have a traffic accident. Other than alcohol, marijuana is the most commonly detected drug in drivers.

Amanda Gardner writes in USA TODAYs blog Your Life,

Marijuana may interfere with reaction times and coordination, among other things, experts say. The authors of the new study said it is critical to determine the excess crash risk related to marijuana in different doses, strengths, and administration methods, such as smoking versus vaporization.

Gardner reports that the researchers believe their findings are especially relevant in light of recent moves to legalize medical marijuana in many states. “As more and more states consider medical use of marijuana, there could be health implications,” said study senior author Dr. Guohua Li.

Medical marijuana is now legal in 16 states plus the District of Columbia, and is being considered by other states, although none of the studies the researchers looked at dealt specifically with medical marijuana.

Ryan Sabalow, writing for (which covers Redding, CA, where medical marijuana is legal) looks into the economic impact of medical marijuana in light of the risks it poses:

To hear medical marijuana advocates and insiders tell it, businesses associated with the north state’s medical marijuana trade have gotten a boost — or are outright booming — in the middle of the Great Recession. […]

Advocates and business insiders say during the fall marijuana harvest, growers head to local casinos, retailers and other businesses with wads of cash in hand.

‘This is a big economy,’ said Jess Brewer, the owner of two Trusted Friends collectives in Redding. […]

[Joel Hay, a professor of pharmaceutical economics and policy at the University of Southern California] said the economic benefits of so much marijuana dealing are far offset by the increased costs that come with so many people using the drug. He points to a loss of productivity at the workplace, an increase in car accidents caused by people driving while high and the increased risk of schizophrenia, which studies show marijuana users face.

Marijuana advocates counter the risks are overstated, and they say the government already has made legal more dangerous drugs, including alcohol, tobacco and pharmaceutical drugs.

On’s blog HealthPop, Ryan Jaslow quotes Chuck Farmer, director of statistics at the Insurance Institute for Highway Safety in Arlington, VA:  “We can’t really say yet that marijuana increases the risk by two or three times. Most of their studies pointed to a very strong bad effect of marijuana on driving, but there are other studies out there that actually go the other way.”

But Jonathan Adkins, spokesperson for the Governors Highway Safety Association, said the association strengthened its drugged driving policy in September. “We see this as a national priority and are seeking a range of actions to address the problem comprehensively.”

Image by Rob!, used under its Creative Commons license.

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