NCPA - National Center for Policy Analysis

Study Says Danger of Secondhand Smoke Exaggerated

May 16, 2003

A newly released study claiming that the danger of secondhand smoke is greatly overstated has provoked protests from antismoking advocates, according to an article in the Wall Street Journal.

According to the study in the British Medical Journal, based on a generations-long set of California data collected by the American Cancer Society:

  • Exposure to secondhand smoke had no significant effect on death rates from lung cancer or heart disease.
  • The rates were similar for those with spouses who smoked and those with nonsmoking spouses, the study found.

But the study, which was conducted by the University of California at Los Angeles, was funded by tobacco industry, so antismoking activists have already issued press releases discounting it. According to experts in the fields of cancer and heart disease, says the Wall Street Journal:

  • Existing research shows that secondhand smoke boosts cancer mortality by 10 percent to 30 percent.
  • "A 2002 summary of 58 studies by the International Agency for Research on Cancer," says the Wall Street Journal article, "blames exposure to secondhand smoke for a 22 percent increased risk of lung-cancer death in women and a 36 percent higher risk in men."

Jacob Sullum of Reason magazine notes that most of the estimated 50,000 deaths from second-hand annually are usually attributed to heart disease. Based on the epidemiological data in the study, smoking one cigarette a day would be associated with something like a 20 percent increase in lung cancer risk -- as opposed to an increase of roughly 1,000 percent for a pack a day -- but virtually no increase in heart disease risk. The incidence of lung cancer in nonsmokers is so low that the increased cancer risk from second-hand smoke is not considered significant.

"It is generally considered that exposure to environmental tobacco smoke is roughly equivalent to smoking one cigarette per day," the study's authors note.

Source: Marilyn Chase and Vanessa O'Connell, "Does Passive Smoke Kill?

Study Sparks Controversy," Wall Street Journal, May 16, 2003; based on James E. Enstrom and Geoffrey C. Kabat, "Environmental tobacco smoke and tobacco related mortality in a prospective study of Californians, 1960-98," Paper, May 17, 2003, British Medical Journal; Jacob Sullum (Reason magazine), "New Grounds for Skepticism About Second-Hand Smoke,", May 16, 2003.

For text (WSJ subscription required),,SB105303450520004600-search,00.html

For BMJ study text


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