Today on Burning Issues Mitch Earleywine is joined by Richard Grucza, PhD, Associate Professor of Psychiatry at Washington University School of Medicine. Grucza received his B.S. from Rochester Institute of Technology in 1989, M.S. from Pennsylvania State University in 1991, Ph. from D. Washington University in 2000, and Master in Psychiatric Epidemiology from Washington University in 2003. Richard Grucza and colleagues published that marijuana use among American adults more than doubled between 2001-2002 and 2012-2013, from 4.1% to 9.5% in the journal JAMA Psychiatry. The new study found there had been no change in the rate of marijuana-related problems, such as addiction, between 2002-2013, contrary to the doubling of such problems reported in the previous study. To comment on the results Grucza says, "We're certainly seeing some increases in marijuana use. But our survey didn't notice any increase in marijuana-related problems. Certainly, some people are having problems so we should remain vigilant, but the sky is not falling."