Texting while driving, speeding and back-seat action aren't all that parents need to worry about when their kids are in cars: Add passive smoking to the list.
In the first national estimate of its kind, a report from U.S. government researchers says more than 1 in 5 high school students and middle schoolers ride in cars while others are smoking.
This kind of secondhand smoke exposure has been linked with breathing problems and allergy symptoms, and more restrictions are needed to prevent it, the report says.
With widespread crackdowns on smoking in public, private places including homes and cars are where people encounter secondhand smoke these days. Anti-smoking advocates have zeroed in on cars because of research showing they're potentially more dangerous than smoke-filled bars and other less confined areas.
The research, from the federal Centers for Disease Control and Prevention, was released online Monday in Pediatrics.
The study is based on national surveys done at public and private high schools and middle schools. Students were asked how often they rode in cars while someone was smoking within the past week. The most common answer was one or two days. The smoker could mean other kids or parents; the study didn't specify.
