Snus is banned as a carcinogenic across the European Union (EU) except in Sweden, although sales are covertly spilling across national borders.
A moist, powdered form of tobacco, snus is not smoked, inhaled or chewed but tucked behind the upper lip, usually contained in a small perforated paper packet.
In a paper published online by The Lancet, Swedish epidemiologists studied 280,000 Swedish construction workers, first of all establishing their tobacco consumption habits and then assessing their health years later.
The first part of the study – assessing the tobacco use – unfolded from 1978 to 1992. The doctors then assessed the volunteers’ health up until 2004.
Compared to counterparts who had never smoked, the snus-takers had about the same level of risk for oral cancer and slighly less risk of lung cancer.
Smokers, though, faced nearly 10 times the risk of lung cancer and more than twice the risk of oral cancer compared with never-smokers.
On the downside, snus takers were around twice as likely as never-smokers to develop cancer of the pancreas, the study said. But smokers were three times higher at risk of this disease compared with the never-smoking group.
The authors stress that their findings are “at odds” with a common perception among snus-takers that their habit is harmless. Snus should be added to the risk factors for pancreatic tumours, they say.
A previous study, carried out in Norway, also highlighted a risk of pancreatic cancer and snus users. Several US studies have also supported those conclusions, although others have not.
In a separate paper, also published by The Lancet, Australian researchers calculated that there could be “substantial health gains” for smokers who switched to snus rather than continuing to smoke.
US public-health expert Jonathan Foulds commented that the two studies add powerfully to the argument for letting snus be considered a less-dangerous – but not a safe – alternative to smoking tobacco.
“We should not delay in allowing snus to compete with cigarettes for market share, and we should be prepared to accurately inform smokers about the relative risks of cigarettes, snus and approved smoking-cessation medications,” said Foulds, of the Tobacco Dependence Programme at New Jersey School of Public Health.
“In light of all the available evidence, the banning or exaggerated opposition to snus in cigarette-rife environments is not sound public-health policy.”
Snus has been found to have lower levels of many toxins compared to other smokeless tobacco.
In addition to the confirmed risk of pancreatic cancer, snus has also been implicated in gum recession and pregnancy complications. The evidence on cardiovascular risk is contradictory.
Premature deaths attributable to tobacco smoking are expected to rise from 5.4 million in 2005 to 6.4 million 2015 and to 8.3 million in 2030, according to research published this year in the journal Public Library of Science (PLoS) Medicine.