Faculty of Geology, University of Science, Vietnam National University, Hanoi (VNU), 334 Nguyễn Trãi Street, Thanh Xuân District, Hanoi, Viet Nam; EOS Geoscience Research Group, Vietnam National University, Hanoi, Viet Nam.
Faculty of Geology, University of Science, Vietnam National University, Hanoi (VNU), 334 Nguyễn Trãi Street, Thanh Xuân District, Hanoi, Viet Nam.
Chemosphere. 2020 Oct;257:127119. doi: 10.1016/j.chemosphere.2020.127119. Epub 2020 May 25.
Radon-based radiation from natural soil building materials is an important factor likely influencing residents' health as a contributing source of natural radiation. This survey aims to quantify the nuclide-specific α-radiation of isotopes Rn and Rn in common types of houses in a region of northern Vietnam, Đồng Văn karst plateau, to preliminarily (i) evaluate the total annual effective dose rates and (ii) assess the relative risk of cancer induction from indoor α-radiation for inhabitants. The average Rn concentrations in all house types were lower than 100 Bq m, but Rn abundances were far higher than Rn, even up to >1000 Bq m in air close to a wall of unfired-soil bricks. The estimated total annual effective dose rates from indoor Rn and Rn and their progenies to residents with daily exposure of 13 h in the various types of houses range from 3.1 to 4.3 mSv a for houses constructed with modified materials, but up to higher than 6 mSv a in houses with raw building materials. The average risk of developing lung cancer as a consequence of a lifetime exposure to indoor α-radiation in affected homes ranges from 3.9% to 14.6%. Rn and its metallic progenies contribute more than 80% of the total average lung cancer risk from total radon, being responsible for a range of 2.7-14.6% of the risk of developing lung cancer.
天然土壤建筑材料中的氡基辐射是影响居民健康的一个重要因素，是天然辐射的一个贡献源。本调查旨在量化越南北部多石高原地区常见类型房屋中氡和钍同位素的核素特异性α辐射，初步（i）评估总年有效剂量率，（ii）评估室内α辐射对居民诱发癌症的相对风险。所有房屋类型的平均 Rn 浓度均低于 100 Bq m，但 Rn 丰度却远高于 Rn，甚至在靠近未烧制土壤砖墙壁的空气中高达 >1000 Bq m。在各种类型的房屋中，居民每天暴露 13 小时时，室内 Rn 和 Rn 及其子体的总年有效剂量率从使用改良材料建造的房屋的 3.1 到 4.3 mSv a 不等，但在使用原始建筑材料的房屋中，总年有效剂量率则高达 6 mSv a 以上。受影响家庭中，由于室内α辐射而终生接触导致肺癌的平均风险从 3.9%到 14.6%不等。Rn 及其金属产物对总氡导致的总平均肺癌风险的贡献超过 80%，对肺癌发病风险的范围为 2.7-14.6%。
