(Reuters Health) – U.S. traffic fatalities rise dramatically on the day pot smokers celebrate as “Weed Day.”
In the quarter-century since High Times magazine proclaimed April 20 a time to light up and smoke marijuana, traffic fatalities have spiked 12 percent on that date, compared to one week before or after, a new study shows.
“This was such a great natural experiment to examine the risk of cannabis intoxication,” said lead author Dr. John Staples, an internist and researcher at the University of British Columbia in Vancouver.
Though the study could not assess whether marijuana-intoxicated drivers caused the surge in vehicle deaths on the counter-cultural “High Holiday” dubbed “4/20,” they appear to be the most likely culprits, Staples said in a phone interview.
“The simplest explanation is that some drivers are impaired by cannabis use, and these drivers are contributing to fatal crashes,” he said. “There should be very clear messaging to the public: don’t drive high.”
The impact of marijuana’s psychoactive effects on drivers is of particular concern given that six U.S. states now permit marijuana to be sold for recreational use to customers at least 21 years old.
Since High Times popularized the date in a story the magazine published in 1991, thousands of Americans have been celebrating the intoxicating properties of cannabis on April 20, the authors write in JAMA Internal Medicine.
Five San Rafael High School students claim to have coined the term “4/20” after regularly meeting at 4:20 p.m. in 1971 to search for a patch of pot plants in a nearby forest.
Staples and Dr. Donald A. Redelmeier analyzed U.S. National Highway Traffic Safety Administration fatality reports from 1992, the year after the High Times story, through 2016. Traffic fatalities were 12 percent more likely on April 20 after 4:20 p.m., the time the