Lung cancer is the second most commonly diagnosed cancer and has the highest death rate of all cancers in the U.S. (Henley et al., 2014). These deaths are largely preventable by eliminating primary and secondhand exposure to tobacco smoke and exposure to radon (Centers for Disease Control and Prevention [CDC], 2016). Although most people are aware that smoking is the primary cause of lung cancer, many do not know that an estimated 25% of lung cancer cases globally occur in nonsmokers, resulting in approximately 300,000 deaths every year (Sun, Schiller, & Gazdar, 2007).
The second leading cause of lung cancer is exposure to radon (Neri, Stewart, & Angell, 2013), resulting in an estimated 15,00022,000 lung cancer deaths every year in the U.S. (Kim, Hwang, Cho, & Kang, 2016). More radon-related lung cancers are diagnosed in individuals with a history of exposure to tobacco smoke. Synergistic risk, or exposure to both tobacco smoke and radon, increases lung cancer risk dramatically (National Research Council, 1999). Radon exposure, however, is a risk for both smokers and nonsmokers. Among never smokers, exposure to radon can be more harmful for those exposed to secondhand smoke (SHS) (Lagarde et al., 2001). Despite the known synergistic risk, there is little public awareness of the combined risks of exposure to tobacco smoke and radon. There is a need to develop and test strategies to motivate individuals to create healthy homes, free of both radon and SHS.
The home is the major source of SHS. Most homeowners can control the quality of the air they breathe by adopting smoke-free home policies. Many adults and children are exposed to SHS, particularly those living in rental properties (Homa et al., 2015; Marano, Schober, Brody, & Zhang, 2009). These households are often composed of less educated parents or headed by a single parent, and they are more likely to report indoor smoking (Zhang, Martinez-Donate, Kuo, Jones, & Palmersheim, 2012). Multiunit housing, where smoking is often allowed, is especially problematic as tobacco smoke moves through air ducts, wall and floor cracks, elevator shafts, and along crawl spaces into other units (King, Cummings, Mahoney, Juster, & Hyland, 2010).
Efforts to separate smokers from their nonsmoker neighbors, to improve ventilation, and/or to increase air cleaning cannot control exposure to SHS in multiunit housing (American Cancer Society, 2018). Those who live in multiunit housing do not have as much control over decision making related to smoking as those who own a single-family residence. A recent study done with a group of renters who were provided with free home radon and airborne nicotine test kits, however, found that stage of action in home testing and adopting a smoke-free home policy increased from study baseline to 3-months postenrollment, showing that this intervention might motivate renters to adopt behaviors for healthier homes (Hahn, Rademacher, Wiggins, & Rayens, 2018). Effective fall 2018, the U.S Department of Housing and Urban Development announced a new rule to prohibit smoking in public housing (Office of the Assistant Secretary for Public and Indian Housing, 2016).
The home is also the major source of radon exposure. Radon, an odorless, colorless radioactive gas, results from the decay of uranium naturally found in soil and rock. Radon can enter a home by diffusion from the soil through concrete floors and walls, foundation cracks, floor drains, sump pumps, construction joints, and cracks or pores in hollow-block walls (Radon Testing Corporation of America, 2010). Despite the potential risk, many individuals might believe there is not a radon problem in their home (Kennedy, Probart, & Dorman, 1991), particularly because radon cannot be detected by human senses (Neri et al., 2013).
According to the U.S. Environmental Protection Agency (U.S. EPA), radon levels [greater than or equal to] 4.0 pCi/L warrant mitigation (Sethi, El-Ghamry, & Kloecker, 2012). Mitigation is the process used to rid a building of detectable levels of harmful substances. The U.S. Surgeon General and the U.S. EPA estimate that 1 in 15 residences in the U.S. exceed 4.0 pCi/L and recommend that every residence be tested for radon (Neri et al., 2013).
Testing indoor air in homes is an underutilized area of prevention. Due to the serious health risks associated with home exposure to radon and tobacco smoke, it is important to examine what factors and characteristics can motivate people to test their homes and ultimately remediate the issue to create homes free of radon and SHS.
The purposes of this study were to 1) examine the prevalence of home testing for radon and SHS at baseline of a randomized controlled trial (RCT) to test the effects of a personalized environmental report-back intervention to reduce home exposure to radon and SHS and
2) look at the associations between testing status and sociodemographic variables.
Design and Sample
The design was a cross-sectional study of the baseline data from a RCT to test the effects of a personalized environmental report-back intervention on exposure to radon and SHS in the home. Homeowners (n = 515) and renters (n = 47) were recruited at a university medical center's outpatient clinics and pharmacy, and at community events in the southeastern U.S. An institutional review board approved the study to assure protection of human subjects.
Homeowners were randomly assigned to treatment (TRT) or control (CTL) groups, and stratified by whether or not there were any smokers living in the home. We continued recruitment and randomization until 515 homeowners were enrolled. Approximately half of the homeowners were in each home-smoking stratum and there was an equal likelihood of being assigned to TRT or CTL groups. Renters were also stratified (with approximately equal strata sizes) by whether or not there were any smokers living in the home, but all renter participants were assigned to the TRT group (renters formed a substudy of the larger RCT).
At enrollment, we provided free...