WASHINGTON » For 50 years now, all tobacco products sold in the United States have had to display tough warnings about the health risks they carry.

But that could change if the maker of a popular Swedish tobacco product called snus convinces a panel of experts convened by the Food and Drug Administration this week that it is less harmful than cigarettes.

Snus (pronounced "snoose") is moist, loose tobacco packaged in a pouch like a tea bag and tucked between the lip and the gums. Starting on Thursday, the company that makes it, Swedish Match, will have two days to try to persuade the FDA and its experts that the traditional smoking warnings are too harsh to describe its product.

Swedish Match is asking the agency for permission to remove the language on snus packages that warns consumers that it could cause mouth cancer, gum disease and tooth loss; the science, Swedish Match contends, shows otherwise. It wants the new warning to say that its products carry "substantially lower risks to health than cigarettes," and argues that snus has been a major reason that tobacco-related cancer rates in Swedish men are the lowest in Europe.

If the FDA panel agrees, it will be the first time since Congress passed the law requiring warning labels in 1965 that any product has gotten a gentler warning. Such a decision could blaze a trail for a far more popular smokeless product, the e-cigarette, which has divided public health experts since appearing on the market less than a decade ago.

It could also reshape U.S. tobacco regulation, tilting it away from requiring the maximum warnings for every product toward a principle of reducing harm. In other words, proponents of this strategy say, smokeless tobacco like snus may not be good for you, but it is not as bad as cigarettes and should be treated that way when it is regulated. The approach is often compared to other harm-reduction strategies, such as giving intravenous drug users clean needles or handing out condoms in high schools.

"Society should have something to offer the 45 million people in the United States who still smoke and are just not able to quit," said Dr. Lars Erik Rutqvist, senior vice president of scientific affairs for Swedish Match.

Under the current policy, which treats all tobacco products as equally dangerous, "these people are being told they should just quit. But they aren’t. They can’t. So they end up being left out there in the cold. I think that’s ethically problematic."

But it is not clear the FDA will buy the argument. In briefing materials released Tuesday, the agency expressed reservations about the company’s proposal, "particularly with respect to whether it adequately reflects the health risks of using snus," and cited studies that found an increased risk of pancreatic cancer, heart attack, stroke, diabetes and bad pregnancy outcomes among snus users.

The two-day meeting will culminate in a vote on Friday. The agency does not have to take the advice from such panels, but it often does.

In 2009, Congress gave the agency the authority to regulate the tobacco industry, including deciding whether to let companies make so-called modified risk claims that their products are less harmful than cigarettes. The Swedish Match proposal is the first such application that the agency has seriously considered.

Rutqvist, a former oncologist, argues that if Swedish Match cannot persuade the FDA, then no one can. The company makes its case in over 135,000 pages using 50 years of data from Sweden’s public health authorities and citing dozens of health studies. He says the product is different from other smokeless tobacco on the U.S. market because it is cured and pasteurized in a way that he says produces fewer toxins.

He checked off the numbers: Just 11 percent of Swedish men smoke, far less than in 1989, when 27 percent smoked. Snus use among men jumped to 21 percent from 17 percent over the same period. Meanwhile, tobacco-related cancer rates among men there have fallen, including for mouth cancer, and are now the lowest in Europe. (The FDA, in its preliminary analysis, said the company cited six studies on snus and oral cancer, with five of them finding no link.)

Approval of Swedish Match’s proposal would offer "a chance for companies to start to communicate truthfully" to addicted American smokers, he said.

But that is exactly what opponents of smoking fear. Tobacco companies have a long history of concealing or lying to the public about the health risks of their products, and mistrust among opponents of smoking runs deep. Swedish Match is requesting that all warnings about specific diseases be removed from its labels, a move that many smoking opponents say is a step too far.

"All of the data from Sweden indicates that products that meet the Swedish standards still increase the risk of cardiovascular disease and pose a risk of pancreatic and esophageal cancer and are harmful if used by pregnant women," said Matthew Myers, president of the Campaign for Tobacco Free Kids, an antismoking group. "There is no mention in the Swedish Match proposal of any of these specific risks."

One big worry is whether labels that indicate lower risk may tempt people — particularly young people — to use tobacco products that they might not have tried otherwise. But company officials say that concern proved to be unfounded in Sweden, and that there is strong evidence that the product helped to bring down smoking rates.

Sabrina Tavernise, New York Times

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