Health Officials Directly Tie More Cancers to Smoking
WASHINGTON -- Smoking is now being blamed for a lot more than lung cancer.
Cigarettes.A World Health Organization panel of 29 cancer experts reviewed scores of cancer and smoking studies and found evidence directly connecting smoking to stomach, liver, cervical and kidney cancers, as well as myeloid leukemia. The U.S. Surgeon General has so far concluded that smoking is linked to those cancers, but hasn't said that smoking causes them.
"These are [cancers] that had not been conclusively [linked] to tobacco smoking in the past," said Patricia Buffler, a researcher on the panel and professor of epidemiology at the University of California at Berkley. "We also hope the public will become aware that the mixture of tobacco smoke is really a very toxic mixture." Ms. Buffler said the links to stomach and liver cancer are most troubling because they are the most common types of cancer in developing countries.
The panel, working for WHO's International Agency for Research on Cancer, noted that half of all regular cigarette smokers will die of a tobacco-related disease. Of those that die of a tobacco-related disease, their average life span is about 20-25 years shorter than a nonsmoker. The group's report said that evidence is growing that quitting smoking by your 30s provides the greatest reduction in risks posed by smoking.
The report said there is evidence that second-hand smoke causes lung cancer in nonsmokers. Beyond that, the data were inconclusive on second-hand smoke's effect on children, the researchers said.
But the report also found that smoking probably doesn't cause cancer of the breast, prostate and uterus.
A spokesman for Philip Morris Cos., New York, the nation's largest cigarette maker, said he couldn't comment on the report because he had not seen it. He referred questions about the company's position to a statement on their Web site. The statement says the company agrees that smoking causes lung cancer and other diseases and directs consumers to rely on advice from public-health experts when deciding whether to smoke.
The Centers for Disease Control and Prevention estimates about 3,000 nonsmokers die a year from lung cancer caused by second-hand smoke.
Ms. Buffler said the panel looked at more than 40 studies on lung cancer and determined that nonsmokers who breathe second-hand smoke have a 20% greater risk of developing lung cancer. Ms. Buffler said the panel estimated about a billion people would die of tobacco-related diseases world-wide this century.