State Health Study Shows Dramatic Drop in Secondhand Smoke Exposure for New Yorkers Since State Clean Indoor Air Act Took Effect in 2003

First Scientific Study to Link the Clean Indoor Air Act to Reduced Exposure

ALBANY, NY, July 19, 2007 – New Yorkers are breathing cleaner air thanks to the state's Clean Indoor Air Act that took effect in July 2003, a new study shows.

The law, which banned smoking in all indoor areas, including restaurants and bars, has reduced non-smoking adults' exposure to tobacco smoke by almost half, according to the state Department of Health study published today in the "Morbidity and Mortality Weekly Report," a publication of the federal Centers for Disease Control and Prevention.

"This is the first time a scientific study has compared non-smokers' exposure to tobacco smoke before and after enactment of a clean indoor air law," said State Health Commissioner Richard F. Daines, M.D. "Given the 47 percent drop in non-smokers' exposure to secondhand smoke, this study proves that clean indoor air laws greatly benefit non-smokers and have the potential to avert disease and save lives. This is a great accomplishment for public health."

"Since prior to the amended Clean Indoor Air Act most New Yorkers were already working in smoke-free workplaces, this study shows how important more casual exposures to smoke can be in restaurants and bars," said Ursula Bauer, PhD., Director of the New York State Tobacco Control Program. "Removing exposures from leisure activities like bowling and bingo and cleaning up the remaining work sites that still permitted smoking have cut in half New Yorkers' exposure to the toxins in tobacco smoke."

Research has shown that tobacco smoke from the burning end of a cigarette or exhaled from a smoker's lungs, known as secondhand smoke or environmental tobacco smoke, causes many of the same diseases in non-smokers who inhale it as smoking causes in smokers. Nationally, secondhand smoke is estimated to kill 50,000 non-smokers a year. Even modest exposures to second-hand smoke have been shown to have adverse impacts. According to a 2006 Surgeon General's Report, there is no safe level of exposure to secondhand smoke.

The New York study tested saliva samples for cotinine, a byproduct of nicotine metabolism, which scientists can measure to determine a person's exposure to tobacco smoke. Saliva samples were obtained from more than 1,500 adult non-smokers living in New York State outside of New York City and Nassau County (both of which had enacted local smoking bans before the statewide ban). Samples were collected before the law went into effect and over the subsequent12 months. The study authors calculated average cotinine levels from samples collected before and after the law went into effect and found the levels fell from 0.078 nanograms per milliliter to 0.041 ng/ml.

The study notes that these substantial reductions in exposure to secondhand smoke would be expected to result in reductions in heart disease and lung cancer and have a positive health impact among non-smokers over time.

Study Highlights

  • Secondhand smoke causes premature death and disease in non-smokers, including heart disease and lung cancer in nonsmoking adults. There is no risk-free level of secondhand smoke exposure.
  • Eliminating smoking in indoor spaces is the only way to fully protect non-smokers from secondhand smoke exposure. Separate smoking sections and ventilation systems are not effective approaches.
  • Previous studies have shown that smoke-free laws are associated with reductions in particulate matter in restaurants and bars, reductions in secondhand smoke exposure in restaurant and bar workers, and improvements in respiratory and sensory symptoms and pulmonary function among these workers.
  • This is the first study to assess changes in a biological marker of secondhand smoke exposure in the general population of nonsmokers following implementation of a state smoke-free law.
  • On July 24, 2003, the State of New York enacted amendments to a State Clean Indoor Air Act that prohibited smoking in most indoor public places and workplaces, including bars and restaurants.
  • Saliva cotinine levels (an objective biological measure of secondhand smoke exposure) among non-smoking participants in the New York Adult Tobacco Survey (NYATS) who submitted saliva samples fell by 47% in the year after New York's smoke-free law took effect.
  • The proportion of these participants with nondetectable levels of cotinine increased from 32% to 52% over the same period.
  • The proportion of all NYATS participants who reported seeing smoking in bars decreased from 52% before the state smoke-free law took effect to 13% a year later.
  • The proportion of NYATS participants who reported seeing smoking in restaurants decreased from 20% before the law took effect to 3% a year later.
  • This study adds to the evidence that comprehensive smoke-free laws substantially reduce non-smokers' secondhand smoke exposure.

Title: Reduction in secondhand smoke exposure among adult non-smokers following implementation of a comprehensive state smoke-free air law — New York, 2003 and 2004

Authors and Affiliations:

  • Ursula Bauer, New York State Department of Health;
  • Matthew Farrelly, Research Triangle Institute International (RTI);
  • Mark Engelen, RTI;
  • David Weitzenkamp, RTI;
  • Andrew Hyland, Roswell Park Cancer Institute;
  • Harlan Juster, New York State Department of Health;
  • James Repace, Repace Associates;
  • Steven Babb, Office on Smoking and Health, CDC.

Methods: The study examined saliva cotinine levels in 1,594 non-smoking respondents to the New York Adult Tobacco Survey (NYATS) before and after implementation of New York's 2003 state law that made almost all workplaces and public places smoke-free. The Adult Tobacco Survey is a telephone survey of adults, funded by DOH.

Findings: Saliva cotinine levels in non-smoking participants in the Adult Tobacco Survey fell by 47 percent after the law took effect. This finding adds to the growing evidence that comprehensive smoke-free air laws reduce non-smokers' exposure to secondhand smoke.

Implications: No previous study has assessed changes in biological markers of secondhand smoke exposure in the general population of non-smokers after the implementation of a comprehensive statewide smoke-free air law. Secondhand smoke contains many toxins and carcinogens and causes an estimated 53,000 deaths a year in the United States. Reducing exposure by this magnitude has the potential to reduce morbidity and mortality. (PDF, 316KB, 28pg.)