BOSTON (AP) - The college years, says University of Maryland senior Andrew Ashwal, are often when smoking becomes a lifelong habit.

"College in general is a time when people experiment with a lot of things," said Ashwal, an anti-smoking activist who says he once experimented with tobacco. "Nicotine is so readily available once you reach 18."

Two studies released Thursday by the Harvard School of Public Health call attention to smoking on college campuses, saying colleges could do more to help their students resist the habit.

The first study, appearing in the March issue of the American Journal of Preventive Medicine, finds that students who live in smoke-free dorms are 40 percent less likely to be smokers than those who live in unrestricted housing.

That may seem obvious, and the authors of the study acknowledge some self-selection is involved, but they insist the study shows how powerful environmental pressures can be for young adults at an age when they are tempted to experiment.

"This is a time in young people's lives when they haven't fully established whether or not they're going to be regular smokers," said Henry Weschler, the studies' principal investigator. "Many are not addicted. Many are trying to give up smoking. Others are experimenting and taking it up."

The study found that among students who were not regular smokers before age 19, only 10 percent who lived in smoke-free dorms were current smokers, compared with 16.9 percent in unrestricted dorms.

"By providing this dorm, you have less time for smoking, and you have fewer peer models for smoking," Weschler said.

The second study, appearing in the March issue of the Journal of American College Health, found that 81 percent of 604 four-year colleges surveyed prohibit smoking in public places, but only 27 percent entirely prohibit smoking in dormitories. It also found that 40 percent of colleges do not offer programs to help students quit, though it acknowledged there is little excess demand for the programs.

Weschler said colleges don't interfere with dormitory smoking because they are reluctant to appear overbearing to their students.

"Colleges like to treat students as young adults, and let them make up their own minds," he said. "But when there are all of these environmental pressures to smoke, they're really not making up their own minds. Either peers influence them, or the marketing practices of tobacco companies influence them."

A previous study found that the number of college students who smoke rose from 22 percent to 28 percent between 1993 and 1997.

Spokesmen for Brown and Williamson and Philip Morris said their companies market only to those 21 and older, and doesn't target colleges.

Philip Morris spokesman Brendan McCormick said his company supports efforts to educate the public, including college students, about the health risks of smoking, but that decisions about whether to ban smoking in dormitories should be left up to colleges "based on what works best for them."

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