title: Atmospheric thorium pollution and inhalation exposure in the largest rare earth mining and smelting area in China.
abstract: Exposure to radionuclide thorium (Th) has generated widespread public concerns, mainly because of its radiological effects on human health. Activity levels of airborne232Th in total suspended particulate (TSP) were measured in the vicinity of the largest rare earth mine in China in August 2012 and March 2013. The mean activity concentrations of232Th in TSP ranged from 820μBqm-3in a mining area in August 2012 to 39,720μBqm-3in a smelting area in March 2013, much higher than the world reference of 0.5μBqm-3. Multistatistical analysis and Kohonen's self-organizing maps suggested that232Th in TSP was mainly derived from rare earth mining and smelting practices. In addition, personal inhalation exposures to232Th associated with respirable particulate (PM10) were also measured among local dwellers via personal monitoring. The mean dose values for different age groups in the smelting and mining areas ranged from 97.86 to 417μSvyear-1and from 101.03 to 430.83μSvyear-1, respectively. These results indicate that people living in the study areas are exposed to high levels of widespread232Th.
authors.affiliation: Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China. Electronic address: wanglq@igsnrr.ac.cn.
authors.forename: Lingqing
authors.initials: L
authors.lastname: Wang
authors.affiliation: Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Buqing
authors.initials: B
authors.lastname: Zhong
authors.affiliation: Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Liang
authors.affiliation: Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, USA.
authors.forename: Baoshan
authors.initials: B
authors.lastname: Xing
authors.affiliation: Department of Environmental Health Sciences, Jonathan and Karin Fielding School of Public Health, University of California, Los Angeles, CA 90095, USA. Electronic address: yifang@ucla.edu.
authors.forename: Yifang
authors.initials: Y
authors.lastname: Zhu
mesh_terms: D000293:Adolescent; D000328:Adult; D000336:Aerosols / Q000032:analysis*; D000396:Air Pollutants, Radioactive / Q000032:analysis*; D002648:Child; D002681:China; D004784:Environmental Monitoring; D006801:Humans; D007223:Infant; D019570:Inhalation Exposure; D008669:Metallurgy; D008685:Meteorological Concepts; D008906:Mining; D008962:Models, Theoretical; D052638:Particulate Matter / Q000032:analysis*; D000069079:Radiation Exposure; D013910:Thorium / Q000032:analysis*
chemical_list: D000336:Aerosols; D000396:Air Pollutants, Radioactive; D052638:Particulate Matter; D013910:Thorium
keywords: Inhalation exposure; PM(10); Rare earth; TSP; Thorium