WASHINGTON — A federal advisory panel, entering the debate over the dangers of "smokeless" tobacco, Wednesday called the use of snuff and chewing tobacco "health-endangering behavior" with "the clear potential for long-term and serious consequences."
"This is not a safe alternative to cigarette smoking," said Dr. Brian MacMahon of the Harvard University School of Public Health, who served as chairman of the committee.
MacMahon, speaking at a news conference, added: "It removes the risk of cancer of the lung but puts you at substantial risk for cancer of the mouth and all of the same risks associated with nicotine and cigarette smoking."
The panel was convened by the National Institutes of Health to address the health consequences of smokeless tobacco, which is used by an estimated 10 million Americans--3 million of them under the age of 21.
While dry snuff is sniffed through the nose in some countries, both chewing tobacco and dry and moist snuff are commonly taken in the mouth in the United States.
The group concluded after a two-day conference that smokeless tobacco strongly contributes to the development of cancers of the mouth and throat, particularly among those who begin using it in childhood. The National Cancer Institute has estimated that 28,900 new cases of oral cancer occurred in 1985, with 9,500 deaths.
The committee, noting that regular users of smokeless tobacco show similar levels of nicotine in their blood as cigarette smokers, said that such nicotine levels can cause increases in blood pressure, heart rates, blood lipids--or fats--and catecholamines, which are hormones that affect mood behavior. It said, however, that there is no data available to establish a link with cardiovascular problems.
The report was attacked immediately by the Smokeless Tobacco Council, an industry group that refused to participate in the conference and which called the study's conclusions "predetermined."
'Vehicle for Attacking'
"The deck is clearly stacked against any fair or unbiased discussion of the unresolved scientific controversy," said Michael J. Kerrigan, president of the council, who charged that the conference was being used as "a vehicle for attacking a consumer product."
Nevertheless, the findings are expected to boost efforts on Capitol Hill to enact legislation that would require health warnings on smokeless tobacco packages and ban television and radio advertising of the product, often promoted by former athletes and entertainers. Broadcast advertising of cigarettes and cigars is already prohibited.
"Now that the dangers have been confirmed, it's clear that Congress should act to stop the widespread use of this substance, particularly by children," said Rep. Henry A. Waxman (D-Los Angeles), chairman of the House Energy and Commerce health subcommittee, who sponsored the legislation. "It's better to stop the use of this product now, rather than face the kind of calamity we're now facing with cigarettes."
Dr. Gregory N. Connolly, director of dental health for the Massachusetts Department of Public Health, agreed. "We have an epidemic of lung cancer because of failure to act in the 1930s and '40s," he said. "We're in an ideal position now to prevent an epidemic of mouth cancer by the year 2000."
Nicotine levels produced by the use of smokeless tobacco are as addictive as cigarettes, the group said. "Some people even sleep with tobacco in their mouth at night," said Travis I. Thompson, professor of psychology at the University of Minnesota, who served on the committee.
Tied to Gum Disease
The panel also said that use of smokeless tobacco is associated with increased gum disease and leukoplakia, or "white patches" in the mouth.
The panel acknowledged that repeated animal studies have failed to provide adequate evidence that smokeless tobacco products induce cancer. However, nitrosamines--chemical substances found in smokeless tobacco--have been found to be highly carcinogenic in animals, the panel said.
The committee said that it based its conclusions about the risk of oral cancer on multiple studies that showed a relationship between oral cancer and chewing of "betel quid" containing tobacco in India and Southeast Asia.
Furthermore, the panel said, this view is "consistent" with that of the International Agency for Research on Cancer, which reported "evidence associating snuff with oral cancer is sufficient to indicate a causal relationship."