Assessment on the influential factors of Radon exposure from school and residential Radon surveys in Korea

Abstract

TPS 782: Health effects of emf, radiation and light, Johan Friso Foyer, Floor 1, August 28, 2019, 3:00 PM - 4:30 PM Background: Radon(222Rn) exposure is the second leading cause of lung cancer. For effective community-level Radon control policies, figuring out the main influential factors affecting Radon exposure and determining the representative value of Radon is important. However, little research has been conducted on recent national Radon surveys in Korea. Objective: To identify 2 main influential factors affecting Radon exposure (geologic factors and building types) using recent school & residential Radon survey data of South Korea and to analyze the association of Radon exposure with lung cancer mortality. Methods: Based on the school(2008~2009) & residential Radon data(2011~2016) from the Korean ministry of Environment, we compared the exposure variation of Radon levels among building types and inferred the amount of geologic influence through Spearman correlation coefficients(We are waiting for additional soil-Radium data and will use it to validate the geologic influence of Radon). Furthermore, we chose ‘detached house (2011~2016)’ as a building type that might maintain consistency in building structures regardless of the location of the buildings. After considering seasonal and temporal variation of exposure, we conducted a Poisson regression analysis to assess the association between regional Radon exposure of detached houses and age adjusted lung cancer mortality rates (2017) controlling for sex and smoking rates. Results: Similar regional exposure variations and moderate & high correlations (r>0.5) between building types indicate high geologic influence on Radon exposure. Despite controlling for potential confounders, the Poisson regression showed no significant associations of Radon and lung cancer (RR=1.001,95%CI:0.999-1.003). Conclusions: The influence of geologic factors and building types on Radon exposure is evident but insignificant association of Radon and lung cancer mortality rates may indicate the inappropriateness of using cross sectional Radon data to represent the whole cumulative exposure of a certain community. To effectively represent the exposure, data that involves housing population and valid exposure duration may be necessary.