Study Finds Secondhand Smoke Has Effect on the Body, Even Outdoors

Nonsmokers who breathe in secondhand smoke outdoors have elevated levels of tobacco-related chemicals in their body, according to a new study. The researchers say their findings suggest this smoke exposure may increase risks of health effects associated with cancer-causing agents in tobacco.

The study, published in Environmental Health Perspectives, included 28 college students who spent three evenings on patios outside a restaurant and bar where smoking was allowed, and at a nonsmoking open-air site. The students sat near smokers at the restaurant and bar, and one of them counted the number of cigarettes lit every 10 minutes, The Wall Street Journal reports.

The researchers collected urine and saliva samples from the students before, immediately after, and the morning after each visit, which lasted three hours.

The study found the students’ levels of cotinine, a nicotine byproduct, were significantly higher in their saliva both right after and the morning after the restaurant and bar visits, compared with the non-smoking site visits. Levels of the chemical NNAL, found in tobacco, were elevated in the students’ urine immediately after the bar and restaurant visits, and continued to be significantly higher the next morning.