What's the Big Deal about Second-Hand Smoke?

Aug. 4, 2004

Kristin Anderson, M.P.H., Ph.D., oncology epidemiology, University of Minnesota, discussed second-hand smoke on the Aug. 4 KARE 11 Today Show.

What’s the big deal about second-hand smoke? Why is it dangerous?

Anderson: According to figures from the Centers for Disease Control and Prevention, secondhand smoke is responsible for at least 3,000 lung cancer deaths and more then 35,000 cardiovascular deaths each year.

The scientific community has suspected for years that exposure to second-hand smoke can exacerbate symptoms of conditions like asthma and plays a role in people developing diseases like cancer and heart attacks. We’re only beginning to understand why and how.

Second-hand Smoke & Cancer

Cigarette smoke contains more than 4,000 chemicals, including 40 known cancer-causing agents. In some cases, secondhand smoke contains higher levels of cancer-causing chemicals than the smoke inhaled by a smoker. More than 30 studies show that people who live with smokers are at increased risk of developing lung cancer.

Researchers at the University of Minnesota followed non-smoking women who visited casinos, where they were exposed to second hand smoke for a period of four hours. When we compared levels of a tobacco-specific carcinogen called NNK from before and after the visit, we found these women had elevated levels of this chemical, which could only come from tobacco smoke. We’d expect that restaurant and bar employees working longer shifts would test positive for even higher levels of this cancer-causing chemical.

Second-hand Smoke & Heart Attacks

A recent study published in the British Medical Journal suggests that exposure to second-hand smoke might also increase risk of heart attacks.

Researchers found that community smoking bans could help reduce the number of heart attacks. The study examined hospital admissions for heart attacks in Helena, Mont., during a six-month smoking ban and compared the data two other periods. The researchers found a 40 percent decrease in heart attack admissions for that same period the previous year and the following six months after the ban was lifted. Residents living around the city had no decrease.

This seems to suggest that reducing people’s exposure to second-hand smoke could help reduce the number of heart attacks.

The Environmental Protection Agency associates second-hand smoke with increased risk of lower respiratory infections like bronchitis and pneumonia in children. In fact, as many as 300,000 of these infections in infants and toddlers could be attributable to second-hand smoke.

There’s no question that tobacco smoke is a health hazard, whether you’re a smoker or you’re exposed to second-hand smoke. New York City and California have implemented bans on smoking in bars and restaurants, as have some communities in Minnesota, including Duluth. The hospital industry leaders expressed fears that the bans would hurt business, but so far there are no conclusive studies to suggest they have been detrimental.

Both Minneapolis and St. Paul have proposed bans, and the scientific evidence suggests curbing smoking in restaurants and bars could improve patrons’ and hospitality employees’ health. Ultimately, the decision will be up to policy makers.

Resources

University of Minnesota's information on second-hand smoke

Environmental Protection Agency

Centers for Disease Control and Prevention