A new scientific study performed by Washington University researchers shows that ventilation systems in indoor venues that allow cigarette smoking do not reduce customers’ exposure to secondhand smoke.

This study, conducted by the Center for Tobacco Policy Research (CTPR) at the George Warren Brown School of Social Work and the Siteman Cancer Center, analyzed nicotine levels and employee hair samples at 10 bars and 10 restaurants in St. Louis and St. Louis County. Sixteen of these establishments allow smoking and four do not.

The study concludes that venues that employ ventilation systems actually have a higher airborne nicotine concentration than venues that do not, suggesting that ventilation systems may be counterproductive in reducing the exposure of secondhand smoke to non-smoking patrons.

The study focused on airborne nicotine because the scientific community holds that airborne nicotine is an accurate indicator of the presence of secondhand smoke. According to researchers, nicotine is found in the air only where cigarettes are smoked.

Stacy Reliford, the government relations director of the local American Cancer Society, is pleased with the study’s findings.

“Obviously we’re excited about the study because I think it’s always great to have local data on the subject [of public tobacco use], and we haven’t seen a lot here in St. Louis,” Reliford said.

Reliford says that finding nicotine in the hair of employees is evidence that they are inhaling and metabolizing secondhand smoke while on the job.

Joaquin Barnoya, research assistant professor in the Department of Surgery at the Washington University School of Medicine, and Sarah Moreland-Russell, research manager for the CTPR, were the primary conductors of the study.

Barnoya, the lead author of the study, highlights the significance of the findings by pointing out that even short-term exposure to secondhand smoke has adverse cardiovascular health effects.

“Some of the effects of secondhand smoke on the cardiovascular system in non-smokers are comparable to the effects of active smoking,” Barnoya said in a statement. “These effects occur within a half hour of exposure.”

Seventy-eight employees from the 20 establishments participated in the study by providing hair samples and completing a questionnaire. Nicotine was present in the hair of all employees, though higher levels were found in smokers.

The employee survey found that 63 percent of workers preferred to work in a non-smoking environment to a smoking one. More than half of smoking employees said that a smoke-free work atmosphere would help them quit, and 70 percent of employees who had smoked in the past responded that a smoke-free workplace would help them abstain from cigarette smoking.

The study was funded by the Barnes-Jewish Hospital Foundation. The Institute for Global Tobacco Control at the Johns Hopkins Bloomberg School of Public Health was also involved with Washington University on the study.

With additional reporting by Alan Liu.