"Restricting these marketing practices would reduce youth smoking," Slater, who led the study, added in a statement.

The study, paid for by the nonprofit Robert Wood Johnson Foundation and the U.S. Centers for Disease Control and Prevention, found the more retail advertising in a community, the higher the odds that nonsmoking teens would experiment with tobacco.

Slater's team studied a nationally representative sample of 26,000 eighth, 10th and 12th graders from 1999 to 2003.

They monitored smoking rates and examined promotions such as cigarette point-of-sale advertising, cigarette price, multi-pack discounts and gifts with purchase.

Such practices make up more than 90 percent of the $13.1 billion that cigarette manufacturers spent on marketing in 2005, according to a Federal Trade Commission report on cigarette marketing released in April.

Slater's team projected that removing point-of-sale cigarette advertising in communities with a moderate level of such advertising in stores -- 2.5 on a 5 point scale -- would reduce the number of teens experimenting with cigarettes by 11.25 percent.

The same communities would see an almost 11 percent increase in experimenters if all stores had the maximum level of advertising, they found.

And every dollar increase in the price of a pack of cigarettes would lower the odds that an adolescent would move to the next level of smoking by 24 percent.

"Our children should not be exposed to Big Tobacco's dirty tricks when they shop in retail stores," said M. Cass Wheeler, chief executive officer of the American Heart Association.

"That's why we need strong federal legislation to make it increasingly difficult for the tobacco industry to addict children and increase their risk for heart disease and stroke," Wheeler said.

The group supports legislation that would allow the U.S. Food and Drug Administration to regulate tobacco products.

The legislation, pending in Congress, would also limit tobacco advertising in stores and would require stores to place tobacco products behind the counter.

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