The National Collegiate Athletic Association (NCAA) has found that the number of college athletes who test positive for marijuana at postseason events has almost tripled, USA Today reports.

According to the article, the number of positive marijuana tests across all three divisions rose to 71 in 2009-10, from 28 in 2008-09. The positive tests represent less than 3 percent of all samples tested by the NCAA, the newspaper notes.

The increase concerns the CEO of the U.S. Anti-Doping Agency, the national anti-doping organization for the Olympics. Tavis Tygart told the newspaper that the increase in positive marijuana tests for student athletes is not a surprise, given the rise in medical marijuana use and calls in some states for legalizing the drug.

“It’s a fear we’ve had that as marijuana and even some performance-enhancing drugs become more socially acceptable that athletes will think it might be acceptable within sports,” he told USA Today.

“It’s too early to tell if this is a one-year spike or indication of a larger problem,” NCAA spokesman Christopher Radford told the newspaper.  He said the NCAA Committee on Competitive Safeguards and Medical Aspects of Sport, which oversees the drug-testing program, is monitoring the issue.