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Ventilation systems ineffective in filtering nicotine, says new WU study

Curran | Flickr
Discarded cigarette butts in a sand receptacle. Eleven people were indicted today over contraband cigarettes in Missouri and Illinois. (via Flickr/ curran.kelleher)

Ventilation systems failed to remove nicotine from smoke-filled air in restaurants and bars in the area, according to a study released Wednesday by Washington University researchers.

University representatives used the results of the study on Wednesday to argue that ventilation systems are ineffective at removing nicotine, putting customers and workers at risk for health problems that include cancer and cardiovascular disease. And they cited the research as the first objective study in St. Louis lending support to comprehensive smoking ban legislation.

"Employees in St. Louis bars and restaurants are exposed to high levels of secondhand smoke while working," said Sarah Moreland-Russell, project manager at Washington University's Center for Tobacco Policy Research. "As there is no safe level of secondhand smoke exposure, the St. Louis area should not delay in the implementation and enforcement of comprehensive smoke-free laws."

Researchers from Siteman Cancer Center and the CTPR put nicotine monitors in 10 local bars and 10 local restaurants for one week. Four of the establishments were voluntarily smoke-free, while the other 16 allowed smoking. Researchers also contacted 78 restaurant and bar workers for their views on smoking in the workplace and took hair samples to measure exposure to secondhand smoke.

The study not only found that air ventilation systems failed to reduce nicotine levels, but it also revealed that places with the systems actually had higher air concentrations of nicotine than in places that lacked systems and had a comparable number of smokers. The researchers speculated that the ventilation systems may have recycled nicotine-filled air back into the bars and restaurants.

Additionally, more than 60 percent of workers said they preferred to work in a smoke-free environment, regardless of whether they smoke. A majority of smoking employees also said smoking ban legislation would help them quit, and 70 percent of nonsmokers said such legislation could help them stay nonsmokers.

Voters in St. Louis County passed a smoking ban in November 2009 that will take effect in January 2011. Opponents had argued that air filtration and ventilation systems could provide a reasonable alternative to a smoking ban. The findings on the air ventilation systems and the survey results likely give ammunition to supporters of the ban. They had argued that ventilation systems don't filter toxic chemicals effectively.

"It confirms what the U.S. surgeon general and air conditioning engineers have said -- simply that ventilation systems cannot remove the toxic chemicals in secondhand smoke," said Stacy Reliford, regional government relations director for the American Cancer Society Eastern Missouri.

Bill Hannegan, an outspoken opponent of smoking bans across the region, did not attend the center's presentation. Even so, he is skeptical about the findings based on what he has learned. "We have lots of questions -- what systems they actually studied, what systems were in place in bars and restaurants that were tested," Hannegan said in a telephone interview. "They can talk generically about air filtration, air ventilation, air purification, but we don't know what machines they had in mind or what machines were tested. That's really important because air purification or filtration is a generic term for all sorts of technologies." 

Later, Hannegan said he would like researchers to test the air at the Double D Lounge, a tavern in Brentwood that he said has "five of the most powerful air purification systems ever made running 24/7."

"If the air is found to have a substantial amount of nicotine," he said, "then I'll concede their point."


While Reliford and some Washington University representatives said they have high hopes for the upcoming ban in St. Louis County, they still have some concerns about the exemptions for certain establishments, such as some bars and casino gaming floors. "There are workers left behind who are still going to be exposed," Reliford said.

She hopes the results of this study will boost recent momentum she has seen at the municipal level. Clayton, Brentwood and Kirkwood have already imposed restrictions on smoking.

The researchers don't fully excuse places that are voluntarily smoke-free either, saying that nicotine levels in those places, while far lower, were still in the detectable range. The researchers say that likely happened because some workers choose to smoke right after work and some secondhand smoke finds its way into the building.

Overall, places that allowed smoking had 31 times as much nicotine in the air as voluntarily smoke-free places. Still, the researchers warned that no level of nicotine has proven to be safe. "Even though going voluntarily smoke-free decreases secondhand smoke exposure, it doesn't completely solve the problem," Moreland-Russell said.

Hair samples from all workers in the study contained some traces of nicotine, regardless of smoking status. Moreland-Russell said the nicotine traces on nonsmokers' hair samples could be explained only by exposure to secondhand smoke.

Nonsmoking and smoking workers alike also reported respiratory and sensory symptoms such as coughing, scratchy throat and increased phlegm; the symptoms were more severe in places with greater amounts of smoking.

Washington University has made no secret about its support for smoking restrictions. In July, the university implemented a tobacco ban on all five of its campuses, citing the health of its workers and students.

The university's Moreland-Russell said in an interview afterward that while CTPR cannot take a stance on the county and city smoking bans, it would like to see the exemptions lifted.

Dr. Timothy Eberlein, director of Siteman Cancer Center, told the Beacon that "we support the measure" and, more generally, measures aimed at cleaning up indoor air.

Bars and businesses in the area had expressed concerns that the county and city smoking bans would hurt their businesses. John Postel, a manager at the Highlands Restaurant and Brewery in Kirkwood, said his city's smoking ban has been "good news" for his business and has led to an increase in family guests. But he added that he's "not sure if it's been an evenly distributed success story."

The study's lead author was Joaquin Barnoya, research assistant professor of surgery at Washington University. The study was funded by the Barnes-Jewish Hospital Foundation.

Puneet Kollipara, a Washington University student and former Beacon intern, is a freelance reporter who writes about politics, government and transportation.

This article originally appeared in the St. Louis Beacon.

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