ST. LOUIS — Ventilation systems in restaurants and bars don't protect employees or patrons from secondhand smoke, and venues with the systems had higher levels of nicotine in the air than sites without the devices, researchers in St. Louis said Wednesday.
Researchers from the Siteman Cancer Center at Barnes-Jewish Hospital, the Washington University School of Medicine and the Center for Tobacco Policy Research at the university studied air quality at St. Louis-area bars and restaurants, using airborne nicotine monitors to measure the level of secondhand smoke exposure.
The study found that airborne nicotine levels were 31 times higher in venues where smoking is allowed. Monitors also found the level of nicotine in the air was roughly three times higher at sites with ventilation systems, compared to those without the systems.
"This finding most likely reflects that ventilation systems were actually recycling the air back into the ventilated space," said Sarah Moreland-Russell, research manager of the Center for Tobacco Policy Research, who led the study.
Kathy Harness, director of government relations for the American Lung Association, said, "Ventilation does reduce the level of visible smoke in the air, and the smell, but it doesn't address the toxins or the gases."
David W. Kuneman, Midwest regional director for the smokers' rights group Citizens Freedom Alliance, questioned the findings. He said several other studies have shown that ventilation systems do work to reduce exposure to secondhand smoke.
"There's an awful lot of work out there contradicting what Washington University has found," Kuneman said.
Cities and states are increasingly limiting areas where smoking is allowed. The anti-smoking lobbying group Americans for Nonsmokers' Rights, based in Berkeley, Calif., said 32 states have laws limiting smoking in some combination of workplaces, restaurants and bars. Missouri is not among them, though dozens of communities have passed their own laws.
A smoking ban takes effect Jan. 2 for St. Louis and St. Louis County, but there are several exemptions — casino floors, some hotel rooms and some private clubs.
Experts say more than 126 million nonsmoking Americans are regularly exposed to someone else's tobacco smoke. The U.S. Surgeon General in 2006 cited "overwhelming scientific evidence" that tens of thousands die each year as a result, from heart disease, lung cancer and other illnesses.
The St. Louis researchers analyzed nicotine levels in randomly selected bars and restaurants — 10 of each — in the city of St. Louis and in St. Louis County. Sixteen allowed smoking indoors, and four were smoke-free.
Researchers also analyzed nicotine levels in hair samples from 78 employees of the monitored venues. Those employees also answered survey questions.
Hair samples found nicotine concentrations higher for employees who smoke — but present for nonsmokers, too. Employees responding to the surveys showed high percentages of both smokers and nonsmokers with symptoms often tied to smoking — shortness of breath, coughing, irritated eyes.
Sixty-two percent of survey respondents said they prefer working in a smoke-free environment. More than half of respondents who smoke said smoke-free legislation would help them quit.
The study was funded by the Barnes-Jewish Hospital Foundation.