|Year : 2020 | Volume
| Issue : 4 | Page : 183-187
Passive radium measurements in soil samples from North Western desert of Egypt using LR-115 nuclear track detector
Ahmed Saad Hussein
Department of Security Sciences, Nuclear Security Program, Naif Arab University for Security Sciences, Riyadh, KSA; Department of Radiation and Environmental Protection, Nuclear Power Plants Authority, Cairo, Egypt
|Date of Submission||11-Sep-2020|
|Date of Acceptance||31-Oct-2020|
|Date of Web Publication||30-Dec-2020|
Dr. Ahmed Saad Hussein
Department of Security Sciences, Nuclear Security Program, Naif Arab University for Security Sciences, Riyadh; Department of Radiation and Environmental Protection, Nuclear Power Plants Authority, Cairo
Source of Support: None, Conflict of Interest: None
Background: The knowledge of the distribution of radionuclides and radiation levels in the environment is important for assessing the effects of radiation exposure to human beings. Radium (226Ra) and its ultimate precursor uranium (238U) are the parent sources of radon (222Rn).222Rn is the main natural radiation source of exposure of human beings and has been recognized as a carcinogenic gas. Measurement of radon and radium in soil samples is useful in studying the health risks. Objectives: The purpose of this study was to investigate the radium content in soil samples from northwestern desert of Egypt. Materials and Methods: A total of 40 soil samples were collected from four regions named El-Alamin, El-Dabaa, Marsa Matrouh, and El-Negala cities in northwestern desert of Egypt. The radium contents in soil samples were estimated by sealed cup technique using LR-115 nuclear track detectors. Results: Radium concentration has been found to vary from 11.58 to 29.11 Bq/kg with an average value of 20.63 ± 1.46 Bq/kg. Conclusion: The observed values of radium concentration in all soil samples are less than the permissible value of 370 Bq/kg recommended by the UNSCEAR 2000 and OCED 1979. Hence, the result shows that these areas under study are safe as far as the health hazard effects of radium are concerned.
Keywords: Cup technique, Egypt, LR-115, radium content, soil, western desert
|How to cite this article:|
Hussein AS. Passive radium measurements in soil samples from North Western desert of Egypt using LR-115 nuclear track detector. J Radiat Cancer Res 2020;11:183-7
|How to cite this URL:|
Hussein AS. Passive radium measurements in soil samples from North Western desert of Egypt using LR-115 nuclear track detector. J Radiat Cancer Res [serial online] 2020 [cited 2021 Jan 19];11:183-7. Available from: https://www.journalrcr.org/text.asp?2020/11/4/183/305725
| Introduction|| |
Radium (226Ra) and radon (222Rn) mainly come from naturally occurring uranium (238U) which is present in all types of rocks, soil, building materials, and ground water. 226Ra is one million times more radioactive than the same mass of238U.222Rn has been classified as a human carcinogen.,,,, Environmental radon and its progeny, on average, account for about half of all human exposure to ionizing radiation from natural sources. Increasing attention has been paid to exposure to radon and its associated health risk in both industrialized and developing countries.,
Some radiation hazard indices of the soil samples at various areas in Egypt were investigated, using cup technique with LR-115 and CR-39 nuclear track detectors because of the high potential of being used as building materials.,,,,
The aim of the present work is to determine the radium activity concentrations in soil samples from four cities in the western north desert of Egypt using cup technique with LR-115 nuclear track detectors.
| Materials and Methods|| |
In the present investigation, “sealed cup technique”,14],, was used to study the radium content. A total of 40 soil samples were collected from four cities, 10 samples from each region, in western north desert in Egypt as shown in [Figure 1]. The samples were dried and saved at room temperature to 1 mm grain size, each sample divided into three equal volumes, weighed, and then placed in cylindrical containers made of aluminum. Each sample container was capped tightly to an inverted cylindrical cup of 3.5 cm radius and 11 cm high. A piece of LR-115 type II (Kodak Pathé, France) detector with area 1.5 cm2 is fixed at the top center of the inverted cup. The experimental arrangement is shown in [Figure 2]. This device is called radon only device due to the configuration of the measuring cup and the chemical etching conditions of the irradiated detectors. LR-115 detector is free from self-plate out effect. Thus, it does not record tracks due to self-plating daughters, α-particles of energy 6 MeV (218Po) and 7.69 MeV (214Po).,, The cups were left undisturbed at room temperature for a 3-month exposure time. During this time, α-particles from the decay of radon bombarded the LR-115 detector inside the inverted cup through the α-decay of radium contents of the samples. After the irradiation period, the bombarded detectors were collected and chemically etched in 2.5 M NaOH solution at 60°C during 2 h. Subsequently, α-tracks were counted using an optical microscope. The diffusion cups were calibrated at the National Institute for Measurements and Standards, Cairo, Egypt. During the calibration process, the cups were placed inside a radon chamber with a concentration of 17.4 ± 0.5 kBq/m3 for different exposure times.
The radon activity concentration (CRn) is calculated using the equation:,,,
Where η the track density (tracks/cm2), η the sensitivity factor of LR115 detector (tracks/cm2/d1/Bq/m3), and t the exposure time (d). The value of η depends on the height and radius of the measuring cylinder cup., An effective equilibrium (about 98%) for radon members of the decay series is reached in about 30 days. Once the radioactive equilibrium is established, one may use the radon alpha analyses for the determination of the steady-state activity of radium. The effective radium content (CRa) is calculated using equations:
Where ηRn is the radon decay constant (d-1), h is the distance between the detector and the top of the soil samples (m), A is the area of cross section of the cylindrical cup (m2), M is the mass of the soil samples (kg), and Te is effective exposure time given by:
| Results and Discussion|| |
The calibration coefficient η for radon measurement using the LR-115 detector obtained from the calibration experiment is 0.036 ± 0.006 α–tracks/cm2/d-1 per Bq/m3. This value is in good agreement with that reported by other investigators.,,
[Table 1] represents the values of radium content (CRa) for soil samples collected from four regions in Egypt using the sealed cup technique with LR-115 nuclear track detectors. Radium content values were found to vary from 11.58 to 29.11 Bq/kg with an average value of 20.63 Bq/kg. Maximum value or radium content of 20.11±1.37 Bq/kg has observed in El-Alamin region and minimum value of 111.58±1.66 Bq/kg is found in El-Negala region. The obtained results are within the range (from 5 to 64 Bq/kg) of the UNSCEAR 2000 survey of natural radionuclide content in Egyptian soil.
|Table 1: Passive measurement of radium content in different surface soil samples in Egypt|
Click here to view
The average value of radium content obtained from this study of soil samples is less than the world value of 35 Bq/kg as reported in UNSCEAR 2000 and much lower than the maximum permissible value of 370 Bq/kg for building materials recommended by the UNSCEAR 2000 and OECD 1979. Thus, results reveal that the surface soil samples analyzed radiologically safe and can be used as building materials without posing significant radiological threat to the population.
[Table 2] shows the comparison between the obtained results of radium content (CRa) in surface soil samples collected from different regions in Egypt using passive technique using sealed cup with LR-115 and CR-39 nuclear track detectors. The obtained values of radium content from this study were found to consistent with data obtained by other Egyptian investigators except the maximum values of the study of Youssef et al. 2015 and the study of Ashry et al., 2019 where the soil samples are rich in phosphate, which is used as agricultural fertilizer in the studied region.
|Table 2: The comparison between the obtained results of radium content in soil samples collected from different regions in Egypt using different detectors|
Click here to view
[Table 3] shows radium content (CRa) in soil samples from this study in comparison to these values in some countries using α-spectrometry with LR-115 or CR-39 nuclear track detectors. The table shows the compatibility of the values from this study with the measured values in many regions of the world except Ethiopia,, Ghana, and India. This is because these regions are characterized by a high level of natural background radiation.
|Table 3: The comparison with the other published data in different countries|
Click here to view
| Conclusion|| |
Radium content has been measured successfully using LR-115 detectors by the sealed cup technique. The sealed cup technique is a passive and convenient useful tool for determining the radon exhalation rates as well as the radium contents in some surface soil samples from four cities in western desert of Egypt. The observed values of radium concentration in all soil samples are less than the permissible value of 370 Bq/kg recommended by UNSCEAR 2000 and OCED 1979. Thus, the studied regions are safe as for the health hazard effects of radium are concerned. It is possible to establish a national database of surface soil samples using low-cost passive technique with large-scale screening measurements. The measured values were compared with national and some other countries.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Durrani SA, Ilic R. Radon Measurements by Etched Track Detectors. Singapore: World Scientific; 1997.
Beir IV. Board on Radiation Effects Research, the Health Exposure to Indoor Radon. Washington, DC: National Research Council; 1999.
Tirmarche M, Harrison JD, Laurier D, Paquet F, Blanchardon E, Marsh JW, et al.
ICRP pu?blication 115. Lung cancer risk from radon and progeny and statement on radon. Ann ICRP 2010;40:1-64.
IAEA. International Atomic Energy Agency, National and Regional Surveys of Radon Concentration in Dwellings, Review of Methodology and Measurement Techniques, AQ33; 2015.
UNSCEAR. United Nations Scientific Committee on the Effect of Atomic Radiation: Sources and Effects of Ionizing Radiation, United Nations, New York: UNSCEAR; 2019.
Environmental Protection Agency. Overview EPA's State Indoor Radon Grants: 2019 Activities. Washington, DC: Environmental Protection Agency; 2020.
United Nations Scientific Committee on the Effect of Atomic Radiation. Sources and Effects of Ionizing Radiation. United Nations, New York: United Nations Scientific Committee on the Effect of Atomic Radiation; 2000.
World Health Organization. Handbook on Indoor Radon: A Public Health Prospective. Geneva, Switzerland.: World Health Organization; 2009.
Hafez AF, Hussein AS, Rasheed NM. A study of radon and thoron release from Egyptian building materials using polymeric nuclear track detectors. Appl Radiat Isot 2001;54:291-8.
Abo-Elmaged M, Marie HK, Basha AM. Passive measurements of effective radium content and radon exhalation rates in soil and water samples from Fayoum depression. Egypt Isotope Red Res 2009;41:463-9.
Abd-Elzaher M. An overview on studying 222Rn exhalation rates using passive technique solid state nuclear track detectors. Am J Appl Sci 2012;9:1653-9.
Youssef H, Embaby AA, El-Farrash AH, Laken HA. Radon exhalation rate in surface soil of graduate villages in West Nile Delta, Egypt using can technique. Int J Recent Sci Res 2015;6:3440-6.
Ashry AH, Abou-leila WA, Taha AA, Abd-Elnaeem E. Radium content and radon exhalation rate from natural samples using SSNTD. J Radiat Nucl Appl 2019;4:101-7.
Somogyi G, Hafez AF, Hunyadi I, Toth-Szilagi M. Measurement of exhalation and diffusion parameters of radon in solid by plastic track detectors. Nucl Track 1986;12:701.
Hafez AF. Study of High-Sensitivity Nuclear Track Detectors and Their Use for Measuring Alpha-Radioactivity. PhD Thesis, Institute of Nuclear Research of Hungarian Academy of Sciences; Debrecen, 1986.
Khan MS, Srivastava DS, Azam A. Study of radium content and radon exhalation rates in soil samples of northern India. Environ Earth Sci 2012;12:1581-7.
Somogyi G. The environmental behavior of radium. In: Tech Reports Series No. 310. Vol. 1. Vienna: IAEA; 1990.
Singh M, Singh NP, Singh S, Virk HS. Calibration of radon detectors. Nucl Tracks Meas Rad 1986;12:739.
Somogyi G, Paripas B, Varga ZS. Measurements of radon, radon daughters and thoron concentrations by multi-detector devices. Nucl Track 1984;8:423.
Singh S, Singh B, Kumar A. Natural radioactivity measurements in soil samples from Hamipure District, Himachal Pradesh, India. Radiat Measur 2003;36:547-9.
OECD. Organization for Economic Cooperation and Development: Exposure to radiation from natural radioactivity in building materials, Report by a group of experts of the OECD Nuclear Energy Agency, Paris: OECD; 1979.
Maregu N, Nebere L, Abye N, Dessalegn B and Yibka T. Investigation of radon concentrations and effective radium content in soil and dwellings of Wolaite Sodo Town, Ethiopia. J Radiat Cancer Res 2020;77:248-55.
Maregu N, Bhardwaj MK. Risk assessment of radium content and radon exhalation rates in soil samples of Shire Indastassie Area, Ethiopia. Int J Eng Manag Sci 2015;6:114-8.
Akoto IN, Andam AB, Akiti T, Flectcher JJ. Study of radium and radon exalation rate in soil samples, Offinso Municpality. AIP Conference Proceedings 2109, 100003 (2019); https://doi.org/10.1063/1.511013
Yadav M, Prasad M, Joshi V, Gusain GS, Ramola RC. A comparative study of radium content and radon exhalation rate from soil samples using active and passive techniques. Radiat Prot Dosimetry 2016;171:254-6.
Bala P, Kumar V and Mehra R. Measurements of radon exhalation rate in various building materials and soil samples. J Earth Syst Sci 2007;126:126-31.
Duggal V, Mehra R, Rani A. Study of radium and radon exhalation rate in soil samples from areas of Northern Rajasthan. J Geolog Soc India 2015;86:331-6.
Kakati RK, Kakati L, Ramachandran TV. Measurement of uranium, radium, and radon exhalation rate of soil samples from Karbi Anglong district of Assam, India using EDXRF and can technique method. APCBEE Procedia 2013;5:186-91.
Kumar A, Singh B, Singh S. Uranium, radium, and radon exhalation studies in some soil samples from Una district, Himachal Pradesh, India. Indian J Pure Appl Phys 2001;39:761-4.
Mahamood KN, Divya PV, Vireethkumer V, Prakash V. Dynamic radionuclides activity, radon exhalation rate of soil and assessment of radiological parameters in the coastal regions of Kerala, India. J Radio Analyt Nucl Chem 2020;324:949-61.
Mir FA, Rather SA. Measurement of radioactive nuclides present in soil samples of district Ganderbal of Kashmir province for radiation safety purposes. J Radiat Res Appl Sci 2015;8:155-9.
Singh S, Sharma DK, Dhar S, Kumar A, Kumar A. Uranium, radium and radon measurements in the environs of Nurpur Area Himachal Himalayas, India. Environ Mont Assess 2007;128:301-9.
Singh J, Singh H, Sigh S, Bajwa B. Uranium, radium, radon exhalation studies in some soil samples using plastic track detectors. Indian J Phys 2009;83:1147-53.
Singh BP, Pandit B, Bhardwaj VN, Singh P, Kumar R. Study of radium and exhalation rate in some solid samples using solid state nuclear track detectors. Indian J Pure Appl Phys 2010;48:493-5.
Zubair M, Khan MS, Verma D. Measurements of radium concentration and radon exhalation rates of soil samples collected from some areas of Bulandshar district, Ultra Pradesh, India using plastic track detectors. Int J Radiat Res 2012;10:83.
Abojassim AA, Kadhimand SH, Alasadi AH, Ali AH. Radon, radium concentrations and radiological parameters in soil samples of Amara at Maysan, Iraq. Asian J Earth Sci 2017;10:44-49.
Ismail AH, Jaafar MS. Hazards assessment of radon exhalation rate and radium content in the soil samples in Iraqi Kurdistan using passive and active methods. Int J Environ Ecolog Eng 2010;4:473-6.
Kheder MH. Measurement of radon concentration using SSNTD in Bartella region. AL-Mustansiriyah J Sci 2018;29;4:110-16.
Farid SM. Indoor radon in dwellings of Jeddah city, Saudi Arabia and its correlations with the radium and radon exhalation rates in soil. Indoor Built Environ 2016;25:269-87.
Elzain AA, Mohammed YS, Mohammed KS, Sumaia SM. Radium and radon exhalation studies in some soil samples from Singa and Rabak Towns, Sudan using CR39. Int J Sci Res 2012;3:632-7.
Tabar E, Yakut H, Kus A. Measurement of the radon exhalation rate and effective radium content in soil samples of southern Sakarya, Turkey. Indoor Built Environ 2018;27:278-88.
[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3]