WASHINGTON - The 2010 Monitoring the Future results showing a significant increase in marijuana use among American adolescents over the last year confirm earlier surveys and are profoundly disturbing, addiction medicine experts say.
"The new data stand as one more sign that those who promote 'medical marijuana' and the legalization of marijuana by emphasizing the drug's safety are reducing the perception of risk of use among youth," Dr. Robert L. DuPont, the first director of the National Institute on Drug Abuse (NIDA), said in an interview. "This is translated directly into significantly increased levels of use."
Dr. Mark S. Gold said these perceptions of safety are rooted in lack of awareness about strong data to the contrary.
"Unfortunately, as in the past, drugs of abuse are widely viewed as safe until proven dangerous," said Dr. Gold, Donald R. Dizney Eminent Scholar and distinguished professor at the McKnight Brain Institute at the University of Florida, Gainesville. "Meanwhile, medications - even those that are potentially life-saving - are properly viewed as dangerous until proven safe."
The 2010 Monitoring the Future results, presented at a Dec. 14 press conference, showed that the percentage of American teenagers reporting daily marijuana use increased significantly from 2009 to 2010. The percentage of 8th, 10th, and 12th graders reporting daily marijuana use increased from 1.0% to 1.2%, 2.8% to 3.3%, and 5.2% to 6.1%, respectively. In a statement, Lloyd D. Johnston, Ph.D., principal investigator of the study, called the increase in daily marijuana use among students in all three grades "perhaps the most troublesome" aspect of this upward shift.
The study defines daily or near-daily use as use on 20 or more occasions in the prior 30 days. About 1 in 16 12th graders use marijuana on a daily or near-daily basis, according to the study. However, past-year and past-month reported use increased among 8th graders only.
Attitudes about marijuana use are clearly changing among American adolescents - for the worse. The 2010 results show a decline in the percentage of 8th graders who disapprove of marijuana use, and declines in the percentage of 10th and 12th graders who said they perceived a "great risk" of harm associated with smoking marijuana regularly.
These perceptions exist despite the wealth of evidence on harmful impact of adolescent cannabis use. Dr. Gold said marijuana-related learning problems and accidents are common now among high school and college students.
In addition, he pointed to the inherent dangers of inhaling drug vapors. Nonmedical drug use can cause long-term changes in the brain ("Teens Plus Marijuana: (Still) a Dangerous Mix," Clinical Psychiatry News, July 2008, p. …