Levels of Radon in Soils of Dodoma City, Central Tanzania
DOI:
https://doi.org/10.26437/ajar.v9i1.523Keywords:
Health risk. radon. risk criterion. soil. Tanzania.Abstract
Purpose: Humans receive radiation doses exceeding fifty percent (50%) of the total dose from natural sources as a result of inhaling radon and thoron gases and their daughters. Radon occurs naturally in soils and can diffuse into indoor environments leading to adverse health effects for inhabitants. In this study, measurement of levels of radon gas in soils was performed with the purpose of categorizing areas and highlighting the likelihood of high levels of radon in indoor environments.
Design/Methodology/ Approach: The study targeted the environs of Dodoma where the rapid expansion of human settlements is ongoing or anticipated. For easy access and convenience, the study was conducted in areas located along main roads leading to the nearby towns/cities. Sampling was done by inserting the drilling rod to a depth of approximately one meter (1 m) below ground level with the aid of a heavy hammer. The alpha pump was used to suck the soil gas from the ground through a metallic tube (the capillary probe) and pressed it into the ionization chamber of the measuring instrument (AlphaGUARD). Radon concentration was read directly from the instrument’s display.
Findings: It was found that radon concentrations in soil vary from 18.8 to 233.5 kBq.m-3. Based on the radon risk criterion, surveyed areas range from normal to high radon risk categories.
Research Limitation/Implication: The study only covered a limited area in Dodoma City, and therefore the results may not be representative of the entire city or even the surrounding regions.
Practical Implications: This study is useful in categorizing building areas based on radon risk criterion with the purpose of reducing possibilities of radon-related health risks; mainly lung cancer to the population.
Social Implications: Radon is a proven cause of lung cancer in humans. Therefore, knowledge of radon levels in the study area will help in setting the mitigation measures necessary for public health protection.
Originality / Value/ Novelty: The study demonstrates an approach for estimating radon levels in soils which is beneficial to current and future researchers, environmentalists and regulators, among others.
References
Aburnurad, K.M., & Al Tamimi, M. (2001). Emanation power of radon and its concentration in soil and rocks. Radiation Measurements, 34, 423.
Alonso, H., Rubiano, J.G., Guerra, J.G., Arnedo, M.A., Tejera, A., & Martel, P. R. J. (2019). Assessment of radon risk areas in the Eastern Canary Islands using soil radon gas concentration and gas permeability of soils. Science of the Total Environment, 664, p. 449–60.
Cinelli, G., Tositti, L., Capaccioni, B., Brattich, E., &Mostacci, D. (2014). Soil gas radon assessment and development of a radon risk map in Bolsena, Central Italy. Environmental Geochemistry and Health, 37, 305–319.https://link.springer.com/article/10.1.
Dogjani, S., & Reci, H. (2014). Comparison of Radon Level Concentration in Soils with The Natural Radionuclides Content in Some Regions of Ionain Coastal Area, in Albania. European Scientific Journal, 3, p. 1857 – 7881.
Duval, J.S. (1993). Use of Aerial Gamma-Ray Data to Estimate Relative Amounts of Radon in Soil Gas. In: Gundersen, L.C.S., & Wanty, R.B. (1993), Field Studies of Radon in Rocks, Soils, and Water (1st ed.). CRC Press. https://doi.org/10.1201/9781003070177.
Esan, D.T., Sridhar, M.K.C., Obed, R., Ajiboye, Y., Afolabi, O., Olubodun, B., & Oni, O.M. (2020). Determination of Residential Soil Gas Radon Risk Indices Over the Lithological Units of a Southwestern Nigeria University. Scientific Reports .https://doi.org/10.1038/s41598-020-64217 –8:
EU (European Commission). (1997). Recommendations for the implementation of Title VII of the European Basic Safety Standards Directive (BSS) concerning significant increase in exposure due to natural radiation sources. Radiation Protection 88.
Hubbard, L.M., & Hagberg, N. (1996). Time-variation of the soil gas radon concentration under and near a Swedish house. Environment International, 22[Suppl. 1], 477.
Iskandar, D., Iida, T., Yamazawa, H., Moriizumi, J., Koarashi, J., Yamasoto, K., Yamasaki, K., Shimo, M., Tsujimoto, T., Ishikawa, S., Fukuda, M., & Kojima, H. (2005). The transport mechanisms of 222Rn in soil at Tateishi as an anomaly spot in Japan. Applied Radiation and Isotopes, 63, p. 401 – 408.
Koray, A., Akkaya, G., Kahraman, A. (2014 ). Measurements of radon concentrations in waters and soil gas of Zonguldak, Turkey. Radiation Protection Dosimetry , 162(3), p. 375–381. https://doi.org/10.1093/rpd/nct308.
Kunovska, B., Ivanova, K., Stojanovska, Z., Vuchkov, D., & Zaneva, N. (2013). Measurements of Radon Concentration in Soil Gas of Urban areas, Bulgaria. Romanian Journal of Physics, 58, p. S172–S179.
Lara, E.G., Rocha, Z., Santos, T., Miguel, R.A., Neto, A.D., Menezes, M. A., & Oliveira, A.H., (2011). Distribution of Soil Gas Radon Concentration in the Metropolitan Region of Belo Horizonte, Brazil and Correlations with Litologies and Pedologies. 2011 International Nuclear Atlantic Conference-INAC 2011. ISBN: 978-85-99141-04-5.
Markkanen, M., & Arvela, H. (1992). Radon Emanation from Soils. Radiation Protection Dosimetry, 45, p. 269 – 272.
Mazur, D., Janik, M., Loskiewicz., Olko, P., & Swakon, J. (1999). Measurements of radon concentration in soil gas by CR-39 detectors. Radiation Measurements, 31(1 – 6), p. 295 – 300.
Mishra, U.C., & Ramu, M.C. (1988). Natural radioactivity in houses and mine atmospheres in India. Radiation Protection Dosimetry 24: 25 –28.
NAS (National Academy of Science). (1988 ). Report of the committee on the Biological Effect of Ionizing Radiation. Health Risks of radon and other internally deposited alpha emitters. Washington, DC: National Research Council, National Academy Press.
Neznal M., & Martin, N. (2005). Permeability as an important parameter for radon risk classification of foundation soils. Annals of Geophysics, 40(1), p. 175–80.
Neznal, M., Martin, N, Matolin, M., Barnet, I., & Miksova, J. (2004). The New Method for Assessing the Radon Risk of Building Sites, Czech Geological Survey Special Papers 16, Prague : Czech Geological Survey. https://www.radon-vos.cz/pdf/metodika.pdf.
Nuhu, H., Hashim, S., Aziz Saleh, M., Syazwan Mohd Sanusi, M., Hussein Alomari, A., Jamal, M. H., ... & Hassan, S. A. (2021). Soil gas radon and soil permeability assessment: Mapping radon risk areas in Perak State, Malaysia. Plos one, 16(7), e0254099.
Riley, W. J., Gadgil, A. J., Bonnefous, Y. C., & Nazaroff, W. W. (1996). The effect of steady winds on radon-222 entry from soil into houses. Atmospheric Environment, 30(7), 1167-1176.
Robinson, A.L., Sextro, R.G., & Fisk, W.J. (1997). Soil-gas entry into an experimental basement driven by atmospheric pressure fluctuations - measurements, spectral analysis and model comparison. Atmosphere Environment. 31(10): 1477 –1485.
Saphymo, G. (2014). AlphaGUARD (Portable Radon Monitor) User Manual. http://www. Saphymo.de.
Singh, B., Singh, S., Bajwa, B.S., Singh, J., & Kumar, A. (2011). Soil gas radon analysis in some areas of Northern Punjab, India. Environmental Monitoring Assessment, 174, p. 209–217.
Sun, K; Guo, Q; & Cheng, J.G. (2012). The Effect of Some Soil Characteristics on Soil Radon Concentration and Radon Exhalation from Soil Surface. Journal of Nuclear Science and Technology, 41(11), p. 1113 – 1117. doi: DOI:10.1080/18811248.2004.9726337.
Sundal, A. V., Henriksen, H., Soldal,O., & Strand, T. (2004 ). The influence of geological factors on indoor radon concentrations in Norway. Science of the Total Environment, 328, p. 41–53.
Thu, H. N.P., Thang N.V., & Hao, L.C. (2020). The effects of some soil characteristics on radon emanation and diffusion. Journal of Environmental Radioactivity, 216. https://doi.org/10.1016/j.jenvrad.2020.106189.
UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation). (1993). Sources and Effects of Ionizing Radiation. United Nations Scientific Committee on the Effects of Atomic Radiation, 1993 Report to the General Assembly, with scientific annexes. United Nations sales publication E.94.IX.2. United Nations, New York.
UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation).(1988). Sources, Effects and Risks of Ionizing Radiation. United Nations Scientific Committee on the Effects of Atomic Radiation, 1988 Report to the General Assembly, with annexes. United Nations sales publication E.88.IX.7. United Nations, New York.
UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation). (2000). Sources and effects of ionizing radiation Report to the General Assembly, with scientific annexes. United Nations.: New York.
UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation). (2006). Exposure due to natural radiation sources. New York: United Nations.
USEPA (United States Environmental Protection Agency). (1993). Protocols for Radon and Radon Decay Product Measurement in Homes. Washington, D.C.,: USEPA Publication 402-R-92-003.
Varley, N. R. & Flowers, A.G. (1992). Radon and its correlation with some geological features of the south-west of England. Radiation Protection Dosimetry, 45, p. 245–248.
WHO (World Health Organization). (2009). WHO handbook on indoor radon: a public health perspective. https://www.who.int/publications/i/item/9789241547673.
Downloads
Published
How to Cite
Issue
Section
Categories
License
Copyright (c) 2023 AFRICAN JOURNAL OF APPLIED RESEARCH
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
By submitting and publishing your articles in the African Journal of Applied Research, you agree to transfer the copyright of the Article from the authors to the Journal ( African Journal of Applied Research).
