Indoor Air Quality in Bars and Restaurants Before and After Implementation of Smoke-free Ordinances

Exposure to secondhand smoke is known to be a serious health hazard. Secondhand smoke contains human carcinogens and respirable particulate matter that makes tobacco smoke a dangerous air pollutant. Health problems that are associated with secondhand smoke include lung cancer, heart disease, chronic lung ailments such as bronchitis and asthma, and low birth-weights. Each year, secondhand smoke causes 35,000 people in the United States to die from heart disease. Short periods of exposure to secondhand smoke have also shown to lead to adverse health effects. In healthy volunteers, only 30 minutes of exposure to secondhand smoke compromised function of the coronary arteries of non-smokers in a way that was indistinguishable from smokers.

It is possible to quantify levels of particulate matter from tobacco smoke in the air. PM2.5 is air pollutant particulates that have a diameter smaller than 2.5 microns.

Particulates of this size are easily inhaled deeply into the lungs, and the more particulate matter in the air, the greater the health danger. The U.S. Environmental Protection Agency (EPA) has found that fine particulate air pollutants can penetrate deeply into the lungs and have serious health effects, including increased respiratory symptoms and disease, decreased lung function, and alterations in lung tissue and structure. These particles also carry other dangerous chemicals, including carcinogens, into the lungs. In addition, recent studies suggest adverse respiratory and cardiovascular health impacts from elevated levels of ultrafine (0.1 micron and smaller) particulates.

In order to protect the public’s health, occupational, environmental and public health agencies have all recommended limiting exposure to secondhand smoke through policies prohibiting smoking in indoor environments. In addition, the EPA has set limits of 15 µg/m3 (micrograms per cubic meter) as the average annual level of PM2.5 exposure and 65 µg/m3 as the 24-hour exposure. Smoking in bars and restaurants will often produce particulate levels that exceed these standards.

Policies requiring smoke-free environments are the most effective method for reducing secondhand smoke exposure in public places. In 2005, the Minnesota Partnership for Action Against Tobacco (MPAAT) commissioned a study to assess the impact of smoke-free ordinances on indoor air quality of selected Twin City Metropolitan Area bars and restaurants. Indoor air quality monitoring took place before and after the implementation of smoke-free ordinances that went into effect for Ramsey and Hennepin counties on March 31, 2005. The study was conducted by the Minnesota Institute of Public Health (MIPH) in collaboration with the Center for Energy and the Environment (CEE) with funding from the Minnesota Partnership for Action Against Tobacco. 

Full report (PDF)
Indoor Air Quality in Bars and Restaurants Before and After Implementation of Smoke-free Ordinances in Hennepin and Ramsey Counties (Technical Summary)