“We know that hospitality employees are exposed to secondhand smoke, which is an established cause of lung cancer,” Carpenter said. “These results show that smoke-free legislation effectively reduces exposure and that such legislation protects hospitality employees from a known cancer risk,” Carpenter said.

The study began in 2006 when the researchers analyzed air quality in 23 venues that allowed smoking in Charleston and 11 in Mt. Pleasant. These same venues were tested again in 2008 following passage of local smoke-free ordinances. The City of Charleston established a smoke-free ordinance in public places in July 2007; the Town of Mt. Pleasant followed with a similar ordinance in September 2007.

The study also examined air quality in 10 establishments in North Charleston, which does not have a smoke-free ordinance, and found that air pollution there remains more than three times higher than the U.S. Environmental Protection Agency (EPA) considers safe.