Department of Geosciences, Georgia State University, 38 Peachtree Center Avenue, Atlanta, GA 30303, United States of America.
Department of Geosciences, Georgia State University, 38 Peachtree Center Avenue, Atlanta, GA 30303, United States of America; Critigen LLC, 7555 East Hampden Avenue, Suite 415, Denver, CO 80231, United States of America.
Sci Total Environ. 2019 Jun 10;668:500-511. doi: 10.1016/j.scitotenv.2019.02.257. Epub 2019 Feb 20.
Radon is a naturally released radioactive carcinogenic gas. To estimate radon exposure, studies have examined various risk factors, but limited information exists pertaining to the confluent impact of housing characteristics and geology. This study evaluated the efficacy of housing and geological characteristics to predict radon risk in DeKalb County, Georgia, USA. Four major types of data were used: (1) three databases of indoor radon concentrations (n = 6757); (2) geologic maps of rock types and fault zones; (3) a database of 402 in situ measurements of gamma emissions, and (4) two databases of housing characteristics. The Getis-Ord method was used to delineate hot spots of radon concentrations. Empirical Bayesian Kriging was used to predict gamma radiation at each radon test site. Chi-square tests, bivariate correlation coefficients, and logistic regression were used to examine the impact of geological and housing factors on radon. The results showed that indoor radon levels were more likely to exceed the action level-4 pCi/L (148 Bq/m) designated by the U.S. Environmental Protection Agency-in fault zones, were significantly positively correlated to gamma readings, but significantly negatively related to the presence of a crawlspace foundation and its combination with a slab. The findings suggest that fault mapping and in situ gamma ray measurements, coupled with analysis of foundation types and delineation of hot spots, may be used to prioritize areas for radon screening.
氡是一种天然释放的放射性致癌气体。为了评估氡暴露，研究已经检查了各种风险因素，但有关住房特征和地质综合影响的信息有限。本研究评估了住房和地质特征在美国佐治亚州迪卡尔布县预测氡风险的效果。使用了四种主要类型的数据：（1）室内氡浓度的三个数据库（n=6757）；（2）岩石类型和断层带的地质图；（3）402 个伽马发射原位测量数据库，以及（4）两个住房特征数据库。Getis-Ord 方法用于划定氡浓度热点。经验贝叶斯克里金用于预测每个氡测试点的伽马辐射。卡方检验、二元相关系数和逻辑回归用于研究地质和住房因素对氡的影响。结果表明，室内氡水平更有可能超过美国环境保护署指定的行动水平-4 pCi/L（148 Bq/m），在断层带中，与伽马读数呈显著正相关，但与存在爬行空间基础及其与平板的组合呈显著负相关。研究结果表明，断层测绘和原位伽马射线测量，加上基础类型分析和热点划定，可用于优先进行氡筛选。
