COLUMBUS, Ohio (AP) — As a political science major at Ohio State University, Ida Seitter says, she lit up many a cigarette to help her through the stress of exam season. Right or wrong, they were her security blanket as she toiled through college.

Seitter, now 26, was old enough by then to make her own decisions, she says. She opposes efforts by policymakers in Ohio, New York, California and other states to impose bans on tobacco use not just in buildings at public colleges, but also anywhere on the campus — even in the open air.

“Just back away from me a little bit. I won’t blow it in your face and I’ll try not to be rude,” Seitter says. “At the same time, I think it’s a little discriminatory for a practice that is considered legal.”

Bans on use, advertising and sales of tobacco in all its forms are being enacted or considered at perhaps half of campuses nationwide, sometimes over the objections of student smokers, staff and faculty. The movement is driven by mounting evidence of the health risks of secondhand smoke, the reduced costs of smoke-free dorms and a drive to minimize enticements to smoke at a critical age for forming lifelong habits.

California’s state system will begin to bar tobacco use in 2013. A ban on use and advertising at the City University of New York system goes into effect in September, and the University of Missouri at Columbia is going smoke-free in 2014.

Ohio higher education officials plan a vote next month urging all public campuses to ban tobacco use. That includes Ohio State, one of the nation’s largest universities, which currently bans only indoor smoking.

According to the surgeon general’s report for 2012, tobacco use among people ages 18 to 25 remains at epidemic proportions nationwide. The review found 90 percent of smokers started by age 18, and 99 percent by age 26. About a quarter to a third of college students smoke, studies have found.

The study found the U.S. would have 3 million fewer young smokers if success in reducing youth smoking by state tobacco-cessation programs from 1997 to 2003 had been sustained. Many of the programs have been hit by budget cuts.

Health and education officials, anti-smoking groups and a generation of students who grew up smoke-free are increasingly united on the issue, says Bronson Frick, associate director of Americans for Nonsmokers’ Rights.

“There are many reasons why a college or university may choose to pursue this type of policy, whether secondhand smoke, dorm fires, or other issues,” he says. “They are also questioning what the role of tobacco is in this academic setting, where we’re supposed to be standing for truth and training the next generation of leaders.”

According to data kept by the nonsmokers group, campus tobacco bans have risen from virtually zero a decade ago to 711 today. That includes both four-year and two-year institutions, both public and private.

One of the first campuses to ban tobacco was Ozarks Technical Community College in Springfield, Mo., which endorsed the move in 1999 and put it in place four years later. The school also established a research center that works with other colleges and hospitals pursuing similar moves, now known as the National Center for Tobacco Policy.

Ty Patterson, the center’s director, says Ozarks quickly realized that its previous policy of allowing smoking in designated outdoor areas was impractical and couldn’t be properly enforced.

Forbidding all tobacco use was deemed to be more effective than simply saying no to cigarette smoke, Patterson says.

“When you go smoke-free, you drive smokers to use smokeless tobacco, which is more addictive,” he says.

Cigarette-size cigars containing candy and fruit flavorings, dissolvable strips and lozenges are among the smokeless tobacco products being targeted to youths, according to the surgeon general. The Centers for Disease Control and Prevention says studies show many smokers mix and match such products with cigarettes as they move from smoking to nonsmoking venues.

Compliance with tobacco bans is generally voluntary, and violations come with few, if any, real penalties. Repeat offenders are sometimes subjected to university disciplinary policies, which vary by school.

While precise statistics on the number of campuses curtailing tobacco are elusive, Patterson estimates that one-third to one-half of all higher education institutions have either made the move or are considering it.

Smoking rights advocate Audrey Silk, founder of New York Citizens Lobbying Against Smoker Harassment, says any outdoor ban — whether for a campus, beach or public park — is an attack on the rights of one segment of the population.

“This isn’t a health issue anymore. It’s a moral issue,” she says. “There’s absolutely zero reason for a smoking ban outdoors. They use it as a tool. Harm from smoke outdoors is an excuse to frustrate smokers into quitting because they can’t find a place to light up.”

Silk says it’s not the place of schools to enforce health issues.

“Schools are a business,” she says. “Who assigned them the role of behavior modification? It’s their responsibility to educate. What they’re doing is indoctrinating.”

Tobacco companies have also questioned the role of universities to take such steps. With limited lobbying power at the college level, they have pursued legislation in some states to pre-empt tobacco-control decisions from occurring at any but the state level.

A spokesman for Philip Morris USA Inc., the nation’s largest tobacco company, deferred comment to the company website, which states that some smoking restrictions are justified but that all-out bans “go too far.”

“Smoking should be permitted outdoors except in very particular circumstances, such as outdoor areas primarily designed for children,” it states.

Seitter, who now works as development coordinator for the Columbus Board of Realtors, says budding college smokers often took up the habit after-hours, at venues such as bars that campus tobacco bans don’t reach.

“You find a lot of people start drinking at that age, and many people who don’t consider themselves smokers, they smoke when they drink,” she says. “I would think that atmosphere has more of an effect than somebody smoking on the corner.”