Why American teens are turning from cigarettes to marijuana

A rising share of teens are smoking marijuana – a trend fueled largely by the growing perception among youths that pot use is not harmful, according to a national survey released Wednesday.

Taken together with the decision by voters in Colorado and Washington State to legalize recreational pot – as well as the continued expansion of medical marijuana – the survey points the increasing difficulty of keeping American teens away from marijuana. Indeed, a higher percentage of high school seniors are smoking marijuana monthly than cigarettes.

More than one-third of teenagers acknowledged smoking pot in the past year – continuing a five-year upward trend, the 2012 Monitoring the Future survey found. In addition, 6.5 percent of 12th-graders reported using marijuana daily – a 30-year peak.

These high levels of marijuana use are linked to a diminishing perception of its risk, according to the survey. Some 20.6 percent of 12th-graders see occasional marijuana use as harmful, while 44.1 percent see regular use as harmful. Those are the lowest rates since 1983 and 1979, respectively.

The ballot measures in Colorado and Washington could add to this perception, said Nora Volkow, director of the National Institute on Drug Abuse (NIDA), one of the survey sponsors, at a press conference.

“One of the factors that contributes to people not using drugs is their illegal quality,” she said. “When you start to have a debate and you have some states where this is no longer the case, then that deterrent is no longer present.”

Ms. Volkow said that teens also perceive marijuana as less risky because it can be prescribed for medicinal purposes. This is consistent with previous survey findings on teenagers’ perceptions of prescription drugs such as Vicodin and Oxycontin, which are also seen as less harmful.

Anti-marijuana activists point to clinical evidence that suggests smoking marijuana can cause forms of brain damage, lowering IQ.

“Historically, this dip in the perception leads to increased use, and we have definitely seen that in the survey’s results,” said Gil Kerlikowske, director of the National Drug Control Policy office. “In fact, more students now report smoking marijuana during the past month than they do smoking cigarettes.”

Cigarette and alcohol use has steadily declined in recent years, reaching their lowest levels since the survey started tracking their use in 1975, said Lloyd Johnston, the survey’s principal investigator at the University of Michigan.

During the past year, the percentage of respondents who said they had ever used cigarettes dropped from 11.7 percent to 10.6 percent across 8th-, 10th-, and 12th-grade students. For alcohol, the percentage of respondents who said they had used alcohol dropped from 31.2 percent in 2007 to 26.7 percent in 2012 across the three grade levels, according to the survey.

“That’s a pretty dramatic change considering how acculturated a behavior as alcohol is in this culture,” Mr. Johnston said.

There has also been progress in lowering the use of illicit drugs including Ecstasy, inhalants, and Salvia. But use of prescription stimulants grew. For example, 7.6 percent of 12th-graders said they had used Adderall, up from 5.4 percent in 2009.

“Each new generation of young people deserves the chance to achieve its full potential, unencumbered by the obstacles placed in the way by drug use," Mr. Kerlikowske said in a press release. "These long-term declines in youth drug use in America are proof that positive social change is possible. But now more than ever we need parents and other adult influencers to step up and have direct conversations with young people about the importance of making healthy decisions. Their futures depend on it."

Monitoring the Future is the largest government-sponsored survey of youth drug use. This year, more than 45,000 students from 395 public schools participated in the survey, which is conducted by the University of Michigan and sponsored by the National Institutes for Health and NIDA.