Smoking Conclusively Linked to a Number of Cancers for the First Time in WHO Study
A World Health Organization committee of cancer experts yesterday announced that they have found evidence "directly connecting" smoking to stomach, liver, cervical and kidney cancers and myeloid leukemia, the Wall Street Journal reports (Carroll, Wall Street Journal, 6/20). The 29-member committee, convened by the United Nations' International Agency for Research on Cancer, reviewed more than 3,000 studies involving millions of smokers in the "most comprehensive study of smoking ever undertaken" and the first such study conducted since 1986 (Maugh, Los Angeles Times, 6/20). "These are (cancers) that had not been conclusively (linked) to tobacco smoking in the past," Patricia Buffler, a committee member and a professor of epidemiology at the University of California-Berkeley, said. The U.S. surgeon general has said that "smoking is linked to those cancers, but hasn't said that smoking causes them" (Wall Street Journal, 6/20). The committee said that at least half of the estimated 1.2 billion smokers worldwide will die "prematurely by smoking-related diseases," and half of the deaths "will occur in middle age." Smokers on average have a 20- to 25-year reduction in life expectancy, according to the committee (Los Angeles Times, 6/20). The committee said that the "best way" to prevent early deaths from smoking-related diseases "is to get smokers to quit." Jonathan Samet, chair of the committee and head of epidemiology at the Johns Hopkins School of Public Health, said, "Our group has concluded that any possible public health gains from changes in cigarette characteristics or composition would be minimal by comparison. Changes in cigarettes are not the way to prevent cancer" (Ross, AP/Richmond Times-Dispatch, 6/20).
The study also found the "first definitive evidence" that secondhand smoke leads to lung cancer. The committee examined more than 50 studies on the effects of secondhand smoke and concluded that secondhand smoke increases the risk of lung cancer for nonsmokers by about 20%. According to Buffler, cigarette smoke contains more than 4,000 chemicals, and new studies have found that they "can be measured in body fluids and urine of nonsmokers" (Los Angeles Times, 6/20). The announcement marks the first time an international organization has found a link between secondhand smoke and an increased risk of lung cancer. The committee plans to release the full study later this year (AP/Richmond Times Dispatch, 6/20). Early results of the study are available online.This is part of the California Healthline Daily Edition, a summary of health policy coverage from major news organizations. Sign up for an email subscription.