Siena Davis and Dr. James Johnston, Health Science

Introduction

In the U.S., exposure to radon gas (²²²Rn) is the second leading cause of lung cancer after tobacco smoke.^{(1) 222}Rn is a naturally occurring environmental carcinogen produced during the radioactive decay of uranium-238, which is found in many soils throughout the U.S.⁽²⁾ Because ²²²Rn is a gas, it has the ability to travel through the soil and into homes through cracks in foundation walls. Inhaled ²²²Rn has the potential to emit alpha radiation in the lungs, and longterm exposure is responsible for approximately 21,000 lung cancer deaths per year in the U.S.^{(2) 222}Rn is a colorless, odorless, and tasteless gas, so the only way to know it is in a home is to test for it. The U.S. Environmental Protection Agency (EPA) recommends that all homes be tested for radon and mitigated if levels exceed 4 pCi/L. However, studies show that even in areas with high radon levels, homeowners frequently do not test or mitigate their homes as recommended.^{(1- 2)} Although the proportion of Utah residents who test their homes is unknown, the Utah Department of Environmental Quality estimates that 30% of Utah homes have ²²²Rn levels in excess of 4 pCi/L.⁽³⁾ This study aims to understand the psychosocial factors that influence Utah County residents’ radon testing and mitigation behaviors. Radon-related lung cancer deaths could be reduced if the psychosocial factors that influence radon testing and mitigation were better understood and used to implement effective interventions.

Methodology

To understand Utah County residents’ radon testing and mitigation behaviors, we conducted an observational study to identify social cognitive theory-based differences between testers and non-testers. Subjects (N = 200) are currently being recruited in two groups at the Utah County Health Department (UCHD). Individuals in the study group (n = 100) consist of Utah County residents visiting UCHD’s Division of Environmental Health for the primary purpose of purchasing a radon test kit, which UCHD offers for $10. The comparison group (n = 100) is being recruited from among Utah County residents who visit UCHD’s vital records office. Both the study and comparison group subjects complete a 51-item survey. Survey questions are based on social cognitive theory constructs, including social modeling, self-efficacy, behavioral capability, outcome expectations, and situational factors. Study group subjects receive $5 off the price of the radon test kit, and comparison group subjects receive $5 cash for completion of the survey. During the consent process subjects in the study group are asked to allow study personnel to access their radon test results on-line at www.radon.com using their radon test kit serial number. Subjects whose lab results are above 4 pCi/L will be contacted by phone approximately 90 days after their test results were reported. During this phone call, study personnel will ask participants questions related to actions taken to reduce radon levels in their home. Results will be analyzed by logistic regression to identify demographic and social cognitive factors that influence Utah County residents’ decisions to test their homes for radon.

Results

Data collection is still underway for this study. The results reported here are preliminary and are limited to participants in the comparison group (n = 38). Participants were predominantly female (60.5%) with a mean age range of 25 – 34 yrs. and a median of 3 people per home. Out of the 38 subjects who completed the survey, 81.6% were Caucasian and 34.2% had at least a bachelor’s degree. Among comparison group subjects, 5 (13.2%) reported having tested their home at least once for radon. Subjects who reported testing their home at least once for radon had higher scores for radon knowledge, expectancy beliefs, social modeling, and self-efficacy (Table 1). Statistical significance between testers and non-testers was not performed due to the small number of individuals who had tested their homes, but will be calculated after all subjects have been recruited into the study.

Table 1

Social cognitive factors associated with radon testing among Utah County residents

Discussion

These findings, while preliminary, appear to support previous studies showing that U.S. residents’ lack understanding of radon and the risks associated with radon exposure. Public health outreach programs aimed at increasing awareness and knowledge of radon exposure may help improve testing rates. One interesting, albeit preliminary, finding in this study is the difference in social modeling scores between testers and non-testers. Testers were more likely to have a friend, neighbor, or family member who has tested their home. To our knowledge this is the first study to consider the influence of social modeling on residents’ radon testing behaviors.

Conclusion

Radon testing rates may increase as public health professionals make stronger efforts to increase radon knowledge in Utah County. Furthermore, understanding the influence of social modeling on radon testing behaviors may help guide future interventions to improve radon testing and mitigation rates. However, these findings are preliminary and are based on a small sample size, and additional data is needed before firm conclusions can be drawn.

1. Nissen, M. J., Leach, J. W., Nissen, J. A., Swenson, K. K., & Kehn, H. (2012). Radon testing and mitigation: An intervention in a primary care setting. Journal of Cancer Education, 27(3), 566-572.
2. Riesenfeld, E. P., Marcy, T. W., Reinier, K., Mongeon, J. A., Trumbo, C. W., Wemple, B. E.,& Kaminsky, D. A. (2007). Radon awareness and mitigation in Vermont: A public health survey. Health Physics, 92(5), 425-431.
3. Utah Department of Environmental Quality (2012). Short Term Radom Test Results by County and Zip Code. Retrieved from http://www.radon.utah.gov/docs/2012/Dec/RadonShortTerm2012version7.pdf