Thirdhand Smoke Pollution and Exposure in Ex-Smokers' Homes
Abstracts
Initial Award Abstract |
Tobacco smoke is made up of more than 4,000 chemicals in the form of gases and microscopic particles that can cause illness and death in nonsmokers. When tobacco is smoked indoors, some of these chemicals stick to and build up on indoor surfaces and in dust. Also known as thirdhand smoke (THS), these pollutants can remain for weeks and months and can sometimes be noticed as the unpleasant odor of stale tobacco smoke. It is known that some of the chemicals in THS undergo chemical reactions in the indoor environment, creating new pollutants that can be more dangerous than the original compounds from which they are formed. Very little is currently known about how THS pollutants change over time as they build up in dust and on surfaces. Similarly, very little is known about how nonsmokers are exposed to THS. We propose to investigate the following specific aims: (1) Examine whether THS contains cancer-causing chemicals and other toxic pollutants, (2) Examine how THS changes over time; (2) Examine how THS pollutants are spread throughout a home; (3) Investigate how nonsmokers are exposed to THS in dust and on surfaces; (4) Examine whether former smokers living in homes with high levels of THS pollution are more likely to relapse to smoking. To examine these aims, we will recruit 100 smokers who are enrolled in a smoking cessation intervention through the VA San Diego Healthcare System. Participants' homes will be visited before the smoker quits smoking, and for up to six months after they quit. At each visit, we will collect air, dust, and surface wipe samples in the homes to determine THS pollutants. We will collect urine and finger wipe samples from the youngest nonsmoking resident to examine exposure to THS. We will also check breath carbon monoxide levels to confirm the former smokers have not relapsed. Air, dust, and surface wipe samples will be examined for evidence of THS, especially those chemicals known to cause cancer in humans. Urine samples will be examined for evidence of exposure to THS. Statistical analyses will be conducted to examine the changes in THS of the home over time, and to describe its occurrence throughout a home. Urine samples will be investigated for changes over time and associations with THS pollution. Findings from this study will provide important new information about the make-up of THS. We will learn whether THS contains chemicals known to cause cancer in humans. We will learn how quickly or slowly some THS compounds disappear, while other new secondary compounds emerge. We will learn whether THS can be found in different rooms (living room, bedroom) and at different heights (where an infant and an adult might breath). We will also better understand how nonsmokers may be exposed to THS by inhaling dust or touching surfaces polluted with THS. Finally, we will learn whether THS may make it more difficult for a smoker to quit smoking. There is growing understanding that THS pollution and exposure present new frontiers in tobacco control efforts, especially in private settings that currently fall outside of the protection of tobacco control policies. This study will inform nonsmokers who are at risk of THS, policy makers, and advocacy groups to help better protect nonsmokers from the harmful long-term consequences of tobacco use. |