Experts say Low-Nitrosamine Snus far less dangerous than Marlboros

Source: US Government Agencies: Substance Abuse and Mental Health Services Administration/CAPTs

Is smokeless tobacco really safer than cigarettes? The answer is yes, much safer, if it comes from Sweden, according to a study published in the December issue of Cancer Epidemiology, Biomarkers & Prevention, a journal of the American Association for Cancer Research.

The study asked nine leading tobacco epidemiologists to estimate what the relative risk of death would be for people using a low-nitrosamine form of smokeless tobacco called Snus, when compared to smoking Marlboro or Newport cigarettes. The expert panel estimated that the relative mortality risk was 90 percent lower overall, 70 to 85 percent lower for oral cancers, 97 percent lower for lung cancer and 90 percent lower for heart disease.

Not all smokeless tobacco products are the same. In many parts of the world, smokeless tobacco is a major cause of oral cancer, and high nitrosamines levels are thought to be the reason why. Many smokeless products in the United States are relatively high in nitrosamines. However, Snus, a smokeless tobacco very popular in Sweden, has very low nitrosamine levels because of the way it is manufactured and refrigerated.

Deaths from tobacco-caused diseases have declined sharply in Sweden over the past 20 years at the same time that many adult males either switched from cigarettes to Snus or used Snus exclusively. This finding has led some scientists to speculate that Snus contributed to the reduction in tobacco-attributable deaths in Sweden.

The study, "The Relative Risks of a Low-Nitrosamine Smokeless Tobacco Product Compared with Smoking Cigarettes: Estimates of a Panel of Experts," was funded by the National Cancer Institute. Lead author Dr. David Levy, an economist at the Pacific Institute for Research and Evaluation, said, "We did this study because there seems to be a lot of confusion about the relative dangers of smokeless tobacco compared to cigarettes, even though common sense would suggest that cigarette smoking would be far more dangerous."

The study shows that regulation could change the tobacco market and reduce public health risks. If the U.S. government would regulate nitrosamine levels in smokeless tobacco and communicate factual information to consumers, it could result in some consumers substituting low-nitrosamine smokeless products for the far more hazardous cigarettes.

"The huge difference in relative risk of different tobacco products as judged by leading scientists cries out for a regulatory environment that would force tobacco manufacturers to produce less dangerous tobacco products," said David Sweanor, an adjunct professor of law and medicine at the University of Ottawa.

"This study does not mean that all smokeless tobacco products are 90 percent less risky than cigarettes, so manufacturers shouldn't use the findings to claim that their products are safer than cigarettes," said epidemiologist Gary Giovino of the Roswell Park Cancer Institute. "Even low-nitrosamine smokeless tobacco is riskier than not smoking."

Research Study: The Relative Risks of a Low-Nitrosamine Smokeless Tobacco Product Compared with Smoking Cigarettes: Estimates of a Panel of Experts , Cancer Epidemiology Biomarkers & Prevention Vol. 13, 2035-2042, December 2004