Study: Deadly Crashes Higher on 4/20

marijuana and teen

(TIME)  April 20, also known as “420,” is a day popular with many marijuana smokers who see it as a “national holiday” of sorts and celebrate by getting high. The term “420” originated in the 1970s with a group of California high schoolers who would regularly meet after school at 4:20 p.m. to smoke weed.

Now, according to researchers who looked at 25 years of car crash data, the celebrations around the “holiday” may have serious consequences. Deadly car crashes were 12 percent higher on April 20 after 4:20 p.m. compared to numbers a week before and a week after, they found. For drivers under 21, the crashes were 38 percent higher.

The research letter was published earlier this year in the JAMA Internal Medicine journal.

“The simplest interpretation of our findings is that more drivers are impaired by cannabis on 4/20 and these drivers contribute to fatal crashes,” Dr. John Staples, one of the study’s authors and a clinical assistant professor of medicine and scientist at the University of British Columbia’s Centre for Health Evaluation and Outcome Sciences, told TIME. Read more.