Marijuana use up, alcohol use down among U.S. teens: Report

(CBS/AP) Results from the latest teen survey from the National Institute on Drug Abuse (NIDA) are a mixed bag. The survey showed fewer teens are turning to alcohol and cigarettes than ever before. But the "Monitoring the Future" survey also found that marijuana use is rising steadily among America's teens.

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The findings are based on a survey of 47,000 eighth-, 10th- and 12th-graders conducted by researchers at the University of Michigan on behalf of the NIDA. The researchers found one out of every 15 high school seniors smokes pot on a daily or near-daily basis. That's the highest rate since 1981.

The percentage of teens saying they see "great risk" in using marijuana has dropped in recent years.

"One thing we've learned over the years is that when young people come to see a drug as dangerous, they're less likely to use it," said survey author Dr. Lloyd Johnston, a distinguished senior research scientist at the University of Michigan. "That helps to explain why marijuana right now is rising."

It's the fourth straight year marijuana use grew among teens compared with last decade when pot use declined among teens.

The survey found more than 36 percent of 12th-graders used marijuana in the past year, compared to nearly 32 percent in the 2007 survey. Almost 29 percent of 10th-graders and 12.5 percent of eighth-graders used marijuana in the past year, the survey showed.

The teen students are also turning to the fake stuff. One of every nine high school seniors said they've used synthetic marijuana, sometimes called Spice or K2, within the previous 12 months. This is the first year the survey asked about synthetic pot use. Fake marijuana, sometimes sold on the internet or in drug paraphernalia shops as "potpourri," contains leaves coated with chemicals that provide a similar high when smoked.

Some experts argue smoking synthetic marijuana is like playing "Russian Roulette" because it could contain dangerous chemicals, CBS News reported.

"It's not in the vocabulary of parents, and they need to be aware of it so that when they have that conversation about substance abuse that they are knowledgeable and they talk about this," said White House drug czar Gil Kerlikowske.

A DEA emergency order banning the sale of five chemicals used in the synthetic blends took effect March 1. Many states also have their own laws banning the sale of synthetic marijuana, and the U.S. House passed a bill earlier this month to ban the chemicals.

Alcohol use continued its steady decline since 1980s and hit a historic low for the survey, which began in the 1970s for 12th-graders. Forty percent of 12th-graders reported drinking in the previous 30 days during the 2011 survey, compared to 54 percent in 1991. Declines were reported in other grade levels.

The survey also showed a decline in teen cigarette smoking this year. The number of those who reported smoking in the previous 30 days for the three grades combined was 11.7 percent, compared to 12.8 percent in 2010.

Other drugs showing some evidence of decline in use this year include cocaine, crack cocaine and inhalants.

The full survey results can be found here.