Have nearly half the members of our high school classes of 2002 tried marijuana?

A December Michigan University survey, “Monitoring the Future,” concluded that some 49 percent of American high school seniors experiment with marijuana at least once before graduation. Another finding was that 22 percent smoke marijuana at least once a month.

As the commercials remind us, figures may vary from region to region, but many youngsters and adults close to them contend such findings are not overblown  even for a “college town” such as Lawrence or Manhattan. Further frightening news comes in the reminder that today’s marijuana is different from what might have been in vogue a generation ago. Parents need to be aware that today’s substance is 10 to 20 times stronger than the marijuana with which they might have been familiar.

And it wouldn’t do any harm to point this out to young people who too often are inclined to consider the drug “harmless.”

Pernicious but not harmless, says John P. Walters, director of the Office of National Drug Control Policy, in a special article for the Washington Post. Comments Walters:

“Marijuana directly affects the brain. Researchers have learned that it impairs the ability of young people to concentrate and retain information during their peak learning years, and when their brains are still developing. The THC in marijuana attaches itself to receptors in the hippocampal region of the brain, weakening short-term memory and interfering with the mechanisms that form long-term memory. Do our struggling schools really need another obstacle to student achievement?”

Such reports make a grim joke of the old drug abuse dodge about “victimless crimes.” Even if no accidents occur and even if only the user is mentally and physically impaired, what about the families, friends and loved ones who are affected?

For a long time, we were being told that marijuana was not addictive. It is. John Walters says that “of the 4.3 million Americans who meet the diagnostic criteria for needing drug treatment (criteria developed by the American Psychiatric Assn., not police departments or prosecutors), two-thirds are dependent on marijuana. These are not occasional pot-smokers but people with real problems directly traceable to their marijuana use, including significant health problems, emotional problems and difficulty in cutting down on use. Sixty percent of teens in drug treatment have a primary marijuana diagnosis.”

Soon, area high schools, including two in Lawrence, will be holding commencement activities. Is there a chance that nearly half of the youngsters in these ceremonies have at least tried marijuana and that as many as 22 percent of them use the substance at least once a month?