Browse > Article
http://dx.doi.org/10.15269/JKSOEH.2019.29.2.167

Characteristics of Internal and External Exposure of Radon and Thoron in Process Handling Monazite  

Chung, Eun Kyo (Occupational Safety and Health Research Institute, KOSHA)
Publication Information
Journal of Korean Society of Occupational and Environmental Hygiene / v.29, no.2, 2019 , pp. 167-175 More about this Journal
Abstract
Objectives: The purpose of this study was to evaluate airborne radon and thoron levels and estimate the effective doses of workers who made household goods and mattresses using monazite. Methods: Airborne radon and thoron concentrations were measured using continuous monitors (Rad7, Durridge Company Inc., USA). Radon and thoron concentrations in the air were converted to radon doses using the dose conversion factor recommended by the Nuclear Safety and Security Commission in Korea. External exposure to gamma rays was measured at the chest height of a worker from the source using real-time radiation instruments, a survey meter (RadiagemTM 2000, Canberra Industries, Inc., USA), and an ion chamber (OD-01 Hx, STEP Co., Germany). Results: When using monazite, the average concentration range of radon was $13.1-97.8Bq/m^3$ and thoron was $210.1-841.4Bq/m^3$. When monazite was not used, the average concentration range of radon was $2.6-10.8Bq/m^3$ and the maximum was $1.7-66.2Bq/m^3$. Since monazite has a higher content of thorium than uranium, the effects of thoron should be considered. The effective doses of radon and thoron as calculated by the dose conversion factor based on ICRP 115 were 0.26 mSv/yr and 0.76 mSv/yr, respectively, at their maximum values. The external radiation dose rate was $6.7{\mu}Sv/hr$ at chest height and the effective dose was 4.3 mSv/yr at the maximum. Conclusions: Regardless of the use of monazite, the total annual effective doses due to internal and external exposure were 0.03-4.42 mSv/yr. Exposures to levels higher than this value are indicated if dose conversion factors based on the recently published ICRP 137 are applied.
Keywords
dose conversion factor; effective dose; internal and external exposure; monazite; radon and thoron;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
연도 인용수 순위
1 Ismail Bahari. Radiological and environmental impact of Amang, a TENORM industry in Malaysia. Technologically enhanced naturally occurring radioactive materials INIS-MY-010. Vol 29, Issue 31, 1997. Available from: https://inis.iaea.org/ collection/NCLCollectionStore/_Public/29/041/29041542.pdf
2 Jin YW, Seo SW, Ha WH, Kang JK, Lee DN et al. Health effects of exposure to radon: implications of the radon bed mattress incident in Korea. Epidemiol Health 2019;41:e2019004 p. 1-7   DOI
3 Kim KP, Choi CK, Kim YG, Ji SW, Koo BC et al. Development of internal dose assessment procedure for workers in industries using raw materials containing naturally occurring radioactive materials. Journal of Radiation Protection and Research 2016;41(3):291-300   DOI
4 Maria Quarto, Mariagabriella Pugliese, Giuseppe La Verde, Filomena Loffredo and Vincenzo Roca. Radon exposure assessment and relative effective dose estimation to inhabitants of Puglia region, South Italy. Int. J. Environ. Res. Public Health 2015, 12, 14948-14957; doi:10.3390/ijerph121114948   DOI
5 Mini K, Manujunatha BM, Sreekumar K. Estimation of radioactivity exposure hazard in environmental matrices due to monazite in placer deposits of southwest coast of Tamilnadu, India. International Journal of Emerging Technology and Advanced Engineering 2014;4(6):431-434
6 MoEL(Ministry of Employment and Labor). Exposure limits for chemical substances and physical agents (MoELPublic Notice No. 2018-62). 2018
7 Park DU, Yi SJ, Kim SY, Kwak HS, Lee SH et al. Effective doses estimated according to characteristics of airborne radon and thoron levels generated from some household products. J Environ Health Sci 2019;45(2):99-112
8 Yassin A. Abdel-Razek, Osman. A. Desouky, Ashraf Elshenawy, Amal S. Nasr1, Haitham S. Mohmmed et al. Assessment of the radiation exposures during separation of rare earth elements from monazite mineral. International Journal of Advanced Research 2016;4(7):265-272
9 Alnour IA, Wagiran H, Ibrahim N, Hamzah S, and Elias MS. Determination of the elemental concentration of uranium and thorium in the products and by-products of Amang. tin tailings process. AIP Conference Proceedings 1799, 030003 (2017);10.1063/1.4972913. Standardless ...
10 Celebi N, Ataksor B, Taskin H, Albayrak BN. Indoor radon measurements in Turkey dwellings. Radiat Prot Dosim 2014, Available from: http://dx.doi:10.1093/rpd/ncu329   DOI
11 Chung EK, Kwon JW, Kim KB, Kim JK, Jang JK et al. A study for occupational exposure and assessment method of radon. Research Report of Occupational Safety and Health Research Institute(Pub. No. 2014-814).; 2014. p. 1-95
12 Chung EK, Kim KB. A study on gamma-spectrometric measurement for naturally occurring radioactive material. Research Report of Occupational Safety and Health Research Institute(Pub. No. 2016-769).; 2016. p. 1-84
13 Ekidin A, Kirdin I, Yarmoshenko I, Zhukovsky M. The problems of individual monitoring for internal exposure of monazite storage facility workers. U.S. Department of Energy, Office of Scientific and Technical Information, p. 1-10, 2003. Available from: https://www.osti.gov/etdeweb/servlets/purl/20992905
14 EPA(U.S. Environmental Protection Agency). EPA assessment of risks from radon in homes. Washington, DC: EPA; 402-R-03-003; 2003. Available at: http://www.epa.gov/radiation/docs/assessment/402-r-03-003.pdf
15 WHO, WHO Handbook on indoor radon: A Public Health Perspective. WHO Press, Geneva, 2009
16 IAEA. Radiation protection and NORM residue management in the production of rare earths from thorium containing minerals. IAEA safety report series No 68. Vienna, Austria, 2010;40-241
17 Epstein L, Koch J, Riemer T, Orion I, Haquin G. Radon concentrations in different types of dwellings in Israel. Radiat Prot Dosim 2014;162:605-608   DOI
18 IAEA(International Atomic Energy Agency). Extent of environmental contamination by NORM and technological option for mitigation. IAEA technical report series No 419. Vienna, Austria, 2003;55-163.
19 IAEA. Naturally Occurring Radiative Material(NORM V). Proceedings of an international symposium, IAEA Vienna, 2007
20 IAEA. Radiation protection and management of NORM residues in the phosphate industry. Safety Reports Series: No.78 IAEA Vienna, 2013
21 ICRP(International Commission on Radiological Protection). Lung cancer risk from radon and progeny & statement on radon. ICRP Publication 115, Ann. ICRP 40(1), 2010
22 ICRP. Occupational intakes of radionuclides: Part 3. ICRP Publication 137, Ann. ICRP 46(3-4), 2018
23 ICKL(Information Center of Korea Laws). Surrounding radiation safety management law. Nuclear Safety and Security Commission, 2019