- Email: [email protected]
Radon exhalation rate for phosphate rocks samples using alpha track detectors
JRRAS190_proof ■ 11 September 2015 ■ 1/6 J o u r n a l o f R a d i a t i o n R e s e a r c h a n d A p p l i e d S c i e n c e s x x x ( 2 0 1 5 ) 1 e6
Available online at www.sciencedirect.com
H O S T E D BY
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
ScienceDirect
Journal of Radiation Research and Applied Sciences journal homepage: http://www.elsevier.com/locate/jrras
Radon exhalation rate for phosphate rocks samples using alpha track detectors Q5
Hesham A. Yousef a,*, Gehad M. Saleh b, A.H. El-Farrash c, A. Hamza c a
Physics Department, Faculty of Science, Suez University, Suez, Egypt Nuclear Materials Authority, P.O. Box: 530 El-Maadi, Cairo, Egypt c Physics Department, Faculty of Science, Mansoura University, Mansoura, Egypt b
article info
abstract
Article history:
Solid state nuclear track detectors are used in very broad fields of technical applications
Received 10 June 2015
and successfully applied in different areas of environmental physics and geophysics.
Received in revised form
Radon concentration and surface exhalation rate for phosphate samples from El-Sebaeya
23 August 2015
and Abu-Tartur, Egypt, were measured using nuclear tracks detectors from types CR-39
Accepted 1 September 2015
and LR-115. The average values of radon concentration are 12711.03 and 10925.02 Bqm3
Available online xxx
in El-Sebaeya area using CR-39 and LR-115 detectors, respectively. Also the average values of radon concentration are 15824.16 and13601.48 Bqm3 in Abu-Tartur area using CR-39
Keywords:
and LR-115 detectors, respectively. From the obtained results we can conclude that the
Radon
average values of radon concentration in Abu-Tartur are higher than El-Sebaeya. The
Phosphate
present study is important to detect any harmful radiation which, can be used as reference
Exhalation rate
information to assess any changes in the radioactive background level in the surrounding
SSNTDs
environment.
Passive technique
Copyright © 2015, The Egyptian Society of Radiation Sciences and Applications. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
1.
Introduction
There are three natural isotopes of the radioactive element radon 222Rn originate in the 238U decay series with a half-life of 3.82 days, thoron (220Rn) is in the 232Th chain with a half-life of 55.6 s, actinon (219Rn) is in the 235U series with a half-life of 4 s (IAEA, 2003). Radon can be considered to be of the most dangerous radioactive elements in the environment (Mansur et al., 2005). The most important mechanism of exposure is the inhalation of the short lived decay products of the principal isotope, 222Rn with indoor air. Concentrations of 222Rn and its progeny are usually higher in indoor air than in
outdoor air, exceptions are in tropical regions, where 222Rn concentrations in well ventilated dwellings are essentially the same as in outdoor air (UNSCEAR, 1993). When radon gas is inhaled, densely ionizing alpha particles emitted by deposited short-lived decay products of radon (218Po and 214Po) can interact with biological tissue in the lungs leading to DNA damage (WHO, 2009). The exposure to high level of radon gas through breathing of air increases the risk of lung cancer (Ramadan, 2012). Fertilizers are used for reclaiming the land and improving the properties of crops. Super phosphate is the fertilizer most commonly used in Egypt and it is manufactured from the reaction between sulfuric acid, phosphate rock and water (El-Zakla, Abdel-Ghany, & Hassan, 2007; Rehman,
* Corresponding author. E-mail addresses: [email protected], [email protected] (H.A. Yousef). Peer review under responsibility of The Egyptian Society of Radiation Sciences and Applications. http://dx.doi.org/10.1016/j.jrras.2015.09.002 1687-8507/Copyright © 2015, The Egyptian Society of Radiation Sciences and Applications. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Please cite this article in press as: Yousef, H. A., et al., Radon exhalation rate for phosphate rocks samples using alpha track detectors, Journal of Radiation Research and Applied Sciences (2015), http://dx.doi.org/10.1016/j.jrras.2015.09.002
65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129
JRRAS190_proof ■ 11 September 2015 ■ 2/6
2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Q1
J o u r n a l o f R a d i a t i o n R e s e a r c h a n d A p p l i e d S c i e n c e s x x x ( 2 0 1 5 ) 1 e6
Imtiaz, Faheem, & Matiullah, 2006). Using phosphate fertilizers over a period of decades could eventually increase the radium and uranium content of the soil, which would result in corresponding increasing of the dose from this source (Ashraf, Higgy, & Pimpl, 2004). Phosphate deposit of sedimentary origin contains higher concentration of 238U and its decay products than phosphate from volcanic or biological origin (Korkmaz & Turgut, 2005). The Egyptian phosphate is widely distributed in many localities on the Red Sea, Nile Valley (El-Sebaeya) and Western Desert. The deposits in the first two districts are relatively rich in phosphate and are exploited at several mines, but those of the Western Desert are of low grade except at Abu-Tartur mine (Ahmed, Abbady, El-Kamal, Steinhausler, & El-Arabi, 2001). Abu-Tartur phosphate project is the largest phosphate mines in the Middle East. The mining area is located in the heart of the Western desert of Egypt (60 km from El-Kharga City, and 10 km from the main road between the two Oases El-Kharga and El-Dakhlah) (Ahmed, 2003; Ashraf, 2012), but ElSebaeya area found in the south of Esna city (Luxor), Western Nile Valley. The present work aimed to determine the values of radon concentration and surface exhalation rate for phosphate rocks samples from El-Sebaeya and Abu-Tartur areas, Egypt. The present study is important to detect any harmful radiation which, can be used as reference information to assess any changes in the radioactive background level.
2.
Materials and methods
Radon concentration and surface exhalation rate for phosphate rocks samples collected from El-Sebaeya and AbuTartur areas, Egypt were measured using solid state nuclear track detectors from types CR-39 and LR-115. Ten samples were collected from each region. The samples were crushed, dried in oven at 110 C for 3 h, minced, sieved by 1 mm mesh, weight carefully and sealed for one month in cylindrical containers with dimensions of 6 cm in diameter and 12 cm in height. Each sample container was capped tightly to an inverted cylindrical plastic cover as shown in Fig. 1 in order to get equilibrium. CR-39 (American Technical Plastic, Inc.) and LR-115 (Kodak Pathe, France) detectors of area 1.5 cm 1.5 cm fixed at the bottom center of the inverted plastic cover. During the exposure time of a-particles from the decay of radon and their daughters bombard the detectors in the air volume of the cylindrical containers. After the exposure period CR-39 and LR-115 detectors were removed carefully from the Can. CR-39 detector etched in NaOH solution with condition 6.25 N at 70 ± 1 C for 7 h. After etching CR-39 detectors were washed in distilled water and then dipped for few minutes in a 3% acetic acid solution, washed again with distilled water and finally dried (Zarrag, El-Araby, & Elhaes, 2012). In the case of LR-115 detector etched in 2.5 N of NaOH in water bath at 60 ± 1 C for about one hour. After the chemical etching LR-115 detectors were washed in distilled water and then placed in a solution of (50 ml water þ 50 ml ethyl alcohol) again washed using water and dried in air (Belafrites, 2008). After etching CR-
Fig. 1 e Plastic cylindrical container of the samples.
39 and LR-115 detectors, the tracks were counted using an optical microscope with a magnification of 640. The value of radon concentration in (Bqm3) at secular equilibrium given by the following equation: CRn ¼
r hT
(1)
Where, CRn is radon concentration (Bqm3), r is the track density (track cm2), T is the exposure time (day) and h is the calibration coefficient of CR-39 and LR-115detectors in (tracks cm2 day1/Bqm3) (Hafez, El-Farrash, & Yousef, 2011). Radon surface exhalation rate given by the relation: EA ¼
CVl A T þ 1l ðelT 1Þ
(2)
Where, EA is the surface exhalation rate in (Bqm2 h1), CRn is the radon concentration in (Bqm3 h1), l is the decay constant of radon (h1), V is the effective volume of the Can (m3), A is the area covered by the can (m2) and T is the irradiation time (Rehman et al., 2006; Barooah, Phukan, & Baruah, 2011).
3.
Results and discussion
The values of radon concentration and surface exhalation rate for phosphate samples are listed in Table 1, which represents a comparison between the values of radon concentration and surface exhalation rate which were measured using CR-39 and LR-115 detectors. In El-Sebaeya area the values of radon
Please cite this article in press as: Yousef, H. A., et al., Radon exhalation rate for phosphate rocks samples using alpha track detectors, Journal of Radiation Research and Applied Sciences (2015), http://dx.doi.org/10.1016/j.jrras.2015.09.002
66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130
JRRAS190_proof ■ 11 September 2015 ■ 3/6
3
J o u r n a l o f R a d i a t i o n R e s e a r c h a n d A p p l i e d S c i e n c e s x x x ( 2 0 1 5 ) 1 e6
Table 1 e Comparison between radon concentration and surface exhalation rate using CR-39 and LR-115 detectors. Area
No.
CR-39
LR-115
CRn (Bq m3) El-Sebaeya
EA (Bq m2 h1)
2358.03 ± 50.87 1422.51 ± 39.554 14519.82 ± 126.07 680.66 ± 27.44 34311.30 ± 193.78 17527.71 ± 138.51 12184.84 ± 115.50 4708.32 ± 71.83 29502.39 ± 179.69 9894.73 ± 104.09 12711.03 13109.42 ± 119.80 13811.88 ± 122.96 16240.96 ± 133.33 10164.99 ± 105.50 18679.88 ± 142.99 21699.81 ± 154.11 24595.00 ± 104.11 19198.94 ± 188.09 12738.94 ± 188.09 8001.80 ± 93,61 15824.16
1 2 3 4 5 6 7 8 9 10
Average Abu-Tartur
1 2 3 4 5 6 7 8 9 10
Average
2.12 1.28 13.09 0.61 30.94 15.80 10.99 4.24 26.61 8.92 11.46 11.82 12.45 14.64 9.16 16.84 19.57 22.18 17.31 11.49 7.21 14.26
concentration and surface exhalation rate using CR-39 detector ranged between (680.66 ± 27.44 to 34311.30 ± 198.78) Bqm3 and (0.61 ± 0.02 to 30.94 ± 0.17) Bqm2 h1, respectively. In the case of LR-115, the values of radon concentration and surface exhalation rate ranged between (584.60 ± 54.88 to 29496.68 ± 356.08) Bqm3 and (0.52 ± 0.04 to 26.16 ± 0.22) Bqm2 h1, respectively. In Abu-Tartur area, the values of radon concentration and surface exhalation rate using CR-39 ranged from (8001.80 ± 39.61 to 24595.00 ± 304.11) Bqm3 and (7.21 ± 0.08 to 29.18 ± 0.09) Bqm2h1, respectively. In case of LR-115 detector, the values of radon concentration and surface exhalation rate ranged from (6877.68 ± 171.94 to 21144.59 ± 302.15) Bqm3 and (6.20 ± 0.15 to 19.07 ± 0.27) Bqm2 h1, respectively. The average values of radon concentration equal 12711.03 and 10925.02 Bqm3 in El-Sebaeya area using CR-39 and LR115 detectors, respectively. Also the average values of radon
CRn (Bq m3)
± 0.04 ± 0.03 ± 0.11 ± 0.02 ± 0.17 ± 0.12 ± 0.10 ± 0.06 ± 0.61 ± 0.09
EA (Bq m2 h1)
2024.61 ± 93.28 1220.79 ± 72.44 12478.70 ± 231 584.60 ± 54.88 29496.68 ± 356.08 15066.44 ± 254.48 10471.28 ± 212.15 4044.94 ± 131.86 25361.47 ± 330.17 8502.54 ± 191.17 10925.20 11266.51 ± 220.06 11872.61 ± 225.90 13961.71 ± 325.53 8734.66 ± 193.76 16055.10 ± 262.72 18651.43 ± 283.15 21144.59 ± 302.15 16502.15 ± 266.33 10948.42 ± 216 6877.68 ± 171.94 13601.48
± 0.10 ± 0.11 ± 0.12 ± 0.09 ± 0.12 ± 0.13 ± 0.09 ± 0.13 ± 0.16 ± 0.08
1.82 ± 1.10 ± 11.25 ± 0.52 ± 26.60 ± 13.58 ± 9.44 ± 3.64 ± 22.87 ± 7.66 ± 9.84 10.16 ± 10.70 ± 12.59 ± 7.87 ± 14.48 ± 16.82 ± 19.07 ± 14.88 ± 9.87 ± 6.20 ± 12.26
0.08 0.06 0.20 0.04 0.32 0.22 0.19 0.11 0.29 0.17 0.19 0.20 0.29 0.17 0.23 0.25 0.27 0.24 0.19 0.15
concentration equal 15824.16 and 13601.48 Bqm3 for AbuTartur area using CR-39 and LR-115 detectors, respectively. From the obtained results we can conclude that the average values of radon concentration in Abu-Tartur are higher than El-Sebaeya. Fig. 2 shows the comparison between the values of radon concentration for El-Sebaeya and Abu-Tartur areas using CR-39 detectors. Sample number 5 has a high value of radon concentration, using CR-39 and LR-115 detectors. This means that the values of radon concentration high in this position due to increasing the values of uranium concentration, so that we can save costs and the dig time and concern the dig in this position because, its rich by phosphate ore. A high-grade phosphate product suitable for fertilizers and other phosphate compounds. But sample number 4 has a low value of radon concentration due to this point has a low value uranium concentration and the phosphate ore.
35000
40000
sebaiua
35000
Abu
30000
30000 C (Bqm )
CRn (Bqm-3)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
25000 20000
Sebaiua
Abu Tartur
25000 20000 15000
15000 10000
10000
5000
5000
0
0
1
2
3
4
5
6
7
8
9
Sample number
Fig. 2 e The comparison between the values of radon concentration for El-Sebaeya and Abu-Tartur areas using CR-39 detector.
1
2
3
4
5
6
7
8
9
10
Sample number
Fig. 3 e The comparison between the values of radon concentration for El-Sebaeya and Abu-Tartur areas using LR-115detector.
Please cite this article in press as: Yousef, H. A., et al., Radon exhalation rate for phosphate rocks samples using alpha track detectors, Journal of Radiation Research and Applied Sciences (2015), http://dx.doi.org/10.1016/j.jrras.2015.09.002
66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130
JRRAS190_proof ■ 11 September 2015 ■ 4/6
4
35000
E (Bqm h )
Abu Tartur
25000 20000
EA (Bqm-2h-1)
30
Sebaiua
30000
R² = 1
25 20 15
15000
10
10000
5
5000
0 0
0 2
3
4
5 6 Samples number
7
8
9
Fig. 4 e The comparison between the values of surface exhalation rate for El-Sebaeya and Abu-Tartur areas using CR-39 detector.
Also Fig. 3 shows the comparison between the values of surface exhalation rate using CR-39 detectors for El-Sebaeya and Abu-Tartur areas. From the obtained experimental results of Abu-Tartur area, sample number 7 has a high value of radon concentration, this means that the values of radon concentration high in this position due to increasing the values of uranium concentration and indicate that, it is rich by phosphate ore. But sample number 10 has a low value of radon concentration due to this point has a low value of phosphate ore. Phosphate ores are of two major geological origins, igneous and sedimentary. The composition of phosphate ores varies from one deposit to another. Therefore, phosphate rocks from different sources are expected to behave differently in acidification processes (Adel, Mohsen, Ahmed, Magdy, & Ahmed, 2013). From the results we find that the average values of radon concentration in Abu-Tartur are higher than El-Sebaeya. Fig. 4 gives the comparison between the values of radon concentration for El-Sebaeya and Abu-Tartur using LR-115 detectors. Fig. 5 shows the comparison between the values of surface exhalation rate for El-Sebaeya and Abu-Tartur areas using LR115 detectors. The correlation relation between radon concentration and surface exhalation rate using LR-115 detectors for El-Sebaeya given by Fig. 6 which equal (R2 ¼ 1). Also the correlation relation between radon concentration and surface
30
Sebaiua
5000
10000
15000
20000
25000
Abu Tartur
25 20
30000
35000
CRn (Bqm-3)
10
Fig. 6 e The correlation relation between radon concentration and surface exhalation rate for El-Sebaeya area by using LR-115 detector.
exhalation rate using LR-115 detectors for Abu-Tartur given by Fig. 7 and equal (R2 ¼ 1). It a good agreement between both measurements of radon concentration and surface exhalation rate. The correlation coefficient is linear because the values of exhalation rate depend on radon concentration since the volume of the cup, the area of the sample and decay constant of radon are the same for all samples. A positive correlation has been observed between radon concentration and the exhalation rate in phosphate samples. The radon exhalation study is important for understanding the relative contribution of the material to the total radon concentration found in the phosphate samples and helpful to study radon health hazard. The comparison between the obtained experimental results and the published data in different countries is given by Table 2. The values of radon concentrations in the phosphate are higher than the worldwide limit and the obtained results agreement with Mohamed (2012).
4.
Conclusion
This work is important to detect any harmful radiation in the surrounding environment, which, can be used as reference information to assess any changes in the radioactive
E (Bqm h )
1
EA (Bqm-2h-1)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
J o u r n a l o f R a d i a t i o n R e s e a r c h a n d A p p l i e d S c i e n c e s x x x ( 2 0 1 5 ) 1 e6
25
R² = 1 20
15
15 10
10 5
5 0
0
1
2
3
4
5 6 Sample number
7
8
9
10
Fig. 5 e The comparison between the values of surface exhalation rate for El-Sebaeya and Abu-Tartur areas using LR-115 detector.
0
5000
10000
15000
20000
2500
C
(Bqm )
Fig. 7 e The correlation relation between radon concentration and surface exhalation rate for Abu-Tartur area by using LR-115 detector.
Please cite this article in press as: Yousef, H. A., et al., Radon exhalation rate for phosphate rocks samples using alpha track detectors, Journal of Radiation Research and Applied Sciences (2015), http://dx.doi.org/10.1016/j.jrras.2015.09.002
66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130
JRRAS190_proof ■ 11 September 2015 ■ 5/6
5
J o u r n a l o f R a d i a t i o n R e s e a r c h a n d A p p l i e d S c i e n c e s x x x ( 2 0 1 5 ) 1 e6
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Table 2 e The comparison between the obtained results and the published data for phosphate samples in different countries. Countries Egypt Egypt Egypt (fert.) Libyan Morocco KSU India Iraq Egypt (El-Sebaeya) Egypt (Abu-Tartur)
CRn (Bqm3)
EA (Bqm2h1)
References
2440e29,000 8.90e1675.40 10.00e1244.00 59.3e949.0 66.01e70.23 58.53e145.34 277.78e13.89 13.00e1197.00 584.60e29496.68 6877.68e21144.59
4.16e26.24 0.02e4.12 0.05e2.35 0.061e0.441
Mohamed, 2012 Saad, 2008 Maged & Saad, 1998 Saad, Abdllah, & Husseein, 2013 Fahad, 2001 Zarrag et al., 2012 Kakati, 2014 Jebur et al., 2014 The present work
background level. The search for phosphate rock deposits became a global effort in the 20th century as demand for phosphate rock increased. Phosphate ores used to manufacture super phosphate fertilizer which, most commonly used in Egypt. It is manufactured from the reaction between sulfuric acid, phosphate rock and water. The values of radon concentrations ranged from 680.66 to 34311.30 Bqm3, 8001.80e24595 Bqm3 using CR-39 detector for El-Sebaeya and Abu-Tartur areas, respectively. But using LR-115 detectors were ranged from 584.60 to 29496.68 Bqm3, 6877.68e21144.59 Bqm3 for El-Sebaeya and Abu-Tartur areas, respectively. From the obtained results we find that the average values of radon concentration for Abu-Tartur area are higher than the values of radon concentration for El-Sebaeya area. The variation in the values of radon concentrations is due to the difference in the chemical composition and the geological form of the samples. The obtained results with each other of the activity concentrations of radon using CR-39 and LR-115 detectors are consistent, while the percentage of errors in CR-39 are lower than LR-115. The percentage of error is referring to the partial sensitivity of the detectors, detector material, track density, the etching and counting techniques. CR-39 detector is widely used for radon and considered as the best option to measure the outdoor radon concentration. The results of the present study shall help to determine the positions which have the highest value of radon and phosphate ores. The values of radon concentrations are higher than the range of action levels from 200 to 600 Bqm3 recommended by ICRP (1994). We conclude that the values of radon concentrations in the phosphate are higher than the worldwide limit and not safe for human, so that we must use personal protective masks to protect ourselves from inhalation radon and live far from the studied areas to minimize the exposure time of radiation. Also we must repeat the measurements to detect the variation in the concentration of radioactive radionuclides that affect the surrounding environment.
Uncited reference Q4
Bhardwaj and Gebregergs, 2013.
0.011e0.0311 0.348e0.0174 0.26e2.40 0.52e26.16 6.20e19.07
references
Adel, A. El-Z., Mohsen, M. A., Ahmed, M. A., Magdy, I. K., & Ahmed, A. El-A. (2013). Production of calcium monohydrogenphosphate from Sebaiya phosphate ore leached by nitric acid. Journal of European Chemical Bulletin, 2(10), 752e757. Ahmed, S. S. (2003). Environmental issues in the extraction of phosphate ore from Abu-Tartur mine, Egypt. The International Mining Congress and Exhibition of Turkey e IMCET. Q2 Ahmed, N. K., Abbady, A., El-Kamal, A. H., Steinhausler, F., & ElArabi, A. M. (2001). Studies of natural radioactivity of some Egyptian rock phosphates. Journal of Pure and Applied Physics, 39, 553e560. Ashraf, El M. (2012). Phosphate mining wastes at Abu-Tartur mine area, Western desert of Egypt. Australian Journal of basic and Applied Sciences, 6(10), 231e248. Ashraf, E. M. K., Higgy, R. H., & Pimpl, M. (2004). Radiological impacts of natural radioactivity in Abu-Tartur phosphate deposits, Egypt. Journal of Environmental Radioactivity, 55, 255e267. Barooah, D., Phukan, S., & Baruah, R. (2011). Study of radon exhalation rates using LR-115 (II) nuclear track detectors in coal mining area of the foothills of Mokokchung District, Nagaland. Indian Journal of Pure and Applied Physics, 49, 665e668. Belafrites A.., Natural radioactivity in geological samples from Algeria by SSNTD and gamma-ray spectrometry. IX Radiation Physics & Protection Conference, 15e19 November 2008, Nasr City, Cairo, Egypt. Bhardwaj, M. K., & Gebregergs, H. G. (2013). Measurement of radium content and radon exhalation rate in soil samples of Mekelle city, Ethiopia. International Journal of Science and Nature, 4(1), 182e184. El-Zakla, T., Abdel-Ghany, H. A., & Hassan, A. M. (2007). Natural radioactivity of some local fertilizers. Roman Journal of Physics, 52(5), 731e739. Fahad, M. (2001). Calibration LR-115 for uranium estimation and radon measurement from phosphate and coal. Physics and Chemistry News, 2, 63e65. Hafez, A. F., El-Farrash, A. H., & Yousef, H. A. (2011). Determination of radon concentration in some environmental samples using cup technique. Journal of Environmental Sciences, 40(4), 535e548. IAEA. (2003). Radiation protection against radon in workplaces other than mines. Vienna: Safety Reports Series No. 33, IAEA. ICRP. (1994). Publication (65) protection against radon-222 at home and work. Barking, Essex: UK. Elsevier Science, Ltd.
Please cite this article in press as: Yousef, H. A., et al., Radon exhalation rate for phosphate rocks samples using alpha track detectors, Journal of Radiation Research and Applied Sciences (2015), http://dx.doi.org/10.1016/j.jrras.2015.09.002
66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130
JRRAS190_proof ■ 11 September 2015 ■ 6/6
6 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
J o u r n a l o f R a d i a t i o n R e s e a r c h a n d A p p l i e d S c i e n c e s x x x ( 2 0 1 5 ) 1 e6
Jebur, J. H., & Subber, A. H. (2014). Natural radon. Exhalation rate from fertilizer used in Basra Governorate, Iraq. International of Physics and Research, 4(6), 1e10. Kakati, R. K. (2014). Radon exhalation rate of soil and indoor radon concentration of various places of Karbi Anglonge District of Assam. Journal of Applied Physics, 6(4), 13e16. Korkmaz, B., & Turgut, S. A. (2005). Research on the urea hydrolysis rate in the soil of Thrace region. Journal of Central European Agriculture, 6(2), 107e114. Maged, A. F., & Saad, E. A. (1998). Radon exhalation rate from some fertilizers, clay and potatoes in Egypt. Environmental Management and Health, 9(3), 130e135. Mansur, H. H., Per Khdar, S., Abdulla, Y. H., Muhamad, Q. N., Othman, M. N., & Qader, S. (2005). Measurement of indoor radon levels in Erbil capital by using solid state nuclear track detector. Journal of Radiation Measurement, 40, 544e547. Mohamed, A. E. (2012). An overview on studying 222Rn exhalation rate using passive technique solid state nuclear track detector. American Journal of Applied Sciences, 9(10), 1653e1659. Ramadan, M. R. (2012). Measurement of radon concentration in Iraqi and imported cement. Journal of Thi-Qar Science, 3(2), 63e69.
Rehman, S., Imtiaz, N., Faheem, M., & Matiullah. (2006). Determination of 238U contents in ore samples using CR-39 based radon dosimeter disequilibrium case. Journal of Radiation Measurements, 41, 471e476. Saad, A. F. (2008). Radium activity and radon exhalation rate from phosphate ores using CR-39 online with on electronic radon analyzer Alpha GUARD. Journal of Radiation Measurements, 43, 463e466. Saad, A. F., Abdllah, R. M., & Husseein, N. A. (2013). Radon exhalation from Libyan soil samples measured with the SSNTD technique. Journal of Applied Radiation and Isotopes, 72, 163e168. UNSCEAR. (1993). Sources and effects of ionizing radiation. United Nations Scientific Committee on the Effects of Atomic Radiation. Report to the General Assembly. WHO. (2009). Handbook on indoor Radon, A public health perspective. World Health Organization. Zarrag, A., El-Araby, E. H., & Elhaes, H. (2012). Monitoring of radon concentration in Jazan beach soil. Journal of Applied Sciences Research, 8(2), 823e827. Q3
Please cite this article in press as: Yousef, H. A., et al., Radon exhalation rate for phosphate rocks samples using alpha track detectors, Journal of Radiation Research and Applied Sciences (2015), http://dx.doi.org/10.1016/j.jrras.2015.09.002
22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42
Available online at www.sciencedirect.com
H O S T E D BY
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
ScienceDirect
Journal of Radiation Research and Applied Sciences journal homepage: http://www.elsevier.com/locate/jrras
Radon exhalation rate for phosphate rocks samples using alpha track detectors Q5
Hesham A. Yousef a,*, Gehad M. Saleh b, A.H. El-Farrash c, A. Hamza c a
Physics Department, Faculty of Science, Suez University, Suez, Egypt Nuclear Materials Authority, P.O. Box: 530 El-Maadi, Cairo, Egypt c Physics Department, Faculty of Science, Mansoura University, Mansoura, Egypt b
article info
abstract
Article history:
Solid state nuclear track detectors are used in very broad fields of technical applications
Received 10 June 2015
and successfully applied in different areas of environmental physics and geophysics.
Received in revised form
Radon concentration and surface exhalation rate for phosphate samples from El-Sebaeya
23 August 2015
and Abu-Tartur, Egypt, were measured using nuclear tracks detectors from types CR-39
Accepted 1 September 2015
and LR-115. The average values of radon concentration are 12711.03 and 10925.02 Bqm3
Available online xxx
in El-Sebaeya area using CR-39 and LR-115 detectors, respectively. Also the average values of radon concentration are 15824.16 and13601.48 Bqm3 in Abu-Tartur area using CR-39
Keywords:
and LR-115 detectors, respectively. From the obtained results we can conclude that the
Radon
average values of radon concentration in Abu-Tartur are higher than El-Sebaeya. The
Phosphate
present study is important to detect any harmful radiation which, can be used as reference
Exhalation rate
information to assess any changes in the radioactive background level in the surrounding
SSNTDs
environment.
Passive technique
Copyright © 2015, The Egyptian Society of Radiation Sciences and Applications. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
1.
Introduction
There are three natural isotopes of the radioactive element radon 222Rn originate in the 238U decay series with a half-life of 3.82 days, thoron (220Rn) is in the 232Th chain with a half-life of 55.6 s, actinon (219Rn) is in the 235U series with a half-life of 4 s (IAEA, 2003). Radon can be considered to be of the most dangerous radioactive elements in the environment (Mansur et al., 2005). The most important mechanism of exposure is the inhalation of the short lived decay products of the principal isotope, 222Rn with indoor air. Concentrations of 222Rn and its progeny are usually higher in indoor air than in
outdoor air, exceptions are in tropical regions, where 222Rn concentrations in well ventilated dwellings are essentially the same as in outdoor air (UNSCEAR, 1993). When radon gas is inhaled, densely ionizing alpha particles emitted by deposited short-lived decay products of radon (218Po and 214Po) can interact with biological tissue in the lungs leading to DNA damage (WHO, 2009). The exposure to high level of radon gas through breathing of air increases the risk of lung cancer (Ramadan, 2012). Fertilizers are used for reclaiming the land and improving the properties of crops. Super phosphate is the fertilizer most commonly used in Egypt and it is manufactured from the reaction between sulfuric acid, phosphate rock and water (El-Zakla, Abdel-Ghany, & Hassan, 2007; Rehman,
* Corresponding author. E-mail addresses: [email protected], [email protected] (H.A. Yousef). Peer review under responsibility of The Egyptian Society of Radiation Sciences and Applications. http://dx.doi.org/10.1016/j.jrras.2015.09.002 1687-8507/Copyright © 2015, The Egyptian Society of Radiation Sciences and Applications. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Please cite this article in press as: Yousef, H. A., et al., Radon exhalation rate for phosphate rocks samples using alpha track detectors, Journal of Radiation Research and Applied Sciences (2015), http://dx.doi.org/10.1016/j.jrras.2015.09.002
65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129
JRRAS190_proof ■ 11 September 2015 ■ 2/6
2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Q1
J o u r n a l o f R a d i a t i o n R e s e a r c h a n d A p p l i e d S c i e n c e s x x x ( 2 0 1 5 ) 1 e6
Imtiaz, Faheem, & Matiullah, 2006). Using phosphate fertilizers over a period of decades could eventually increase the radium and uranium content of the soil, which would result in corresponding increasing of the dose from this source (Ashraf, Higgy, & Pimpl, 2004). Phosphate deposit of sedimentary origin contains higher concentration of 238U and its decay products than phosphate from volcanic or biological origin (Korkmaz & Turgut, 2005). The Egyptian phosphate is widely distributed in many localities on the Red Sea, Nile Valley (El-Sebaeya) and Western Desert. The deposits in the first two districts are relatively rich in phosphate and are exploited at several mines, but those of the Western Desert are of low grade except at Abu-Tartur mine (Ahmed, Abbady, El-Kamal, Steinhausler, & El-Arabi, 2001). Abu-Tartur phosphate project is the largest phosphate mines in the Middle East. The mining area is located in the heart of the Western desert of Egypt (60 km from El-Kharga City, and 10 km from the main road between the two Oases El-Kharga and El-Dakhlah) (Ahmed, 2003; Ashraf, 2012), but ElSebaeya area found in the south of Esna city (Luxor), Western Nile Valley. The present work aimed to determine the values of radon concentration and surface exhalation rate for phosphate rocks samples from El-Sebaeya and Abu-Tartur areas, Egypt. The present study is important to detect any harmful radiation which, can be used as reference information to assess any changes in the radioactive background level.
2.
Materials and methods
Radon concentration and surface exhalation rate for phosphate rocks samples collected from El-Sebaeya and AbuTartur areas, Egypt were measured using solid state nuclear track detectors from types CR-39 and LR-115. Ten samples were collected from each region. The samples were crushed, dried in oven at 110 C for 3 h, minced, sieved by 1 mm mesh, weight carefully and sealed for one month in cylindrical containers with dimensions of 6 cm in diameter and 12 cm in height. Each sample container was capped tightly to an inverted cylindrical plastic cover as shown in Fig. 1 in order to get equilibrium. CR-39 (American Technical Plastic, Inc.) and LR-115 (Kodak Pathe, France) detectors of area 1.5 cm 1.5 cm fixed at the bottom center of the inverted plastic cover. During the exposure time of a-particles from the decay of radon and their daughters bombard the detectors in the air volume of the cylindrical containers. After the exposure period CR-39 and LR-115 detectors were removed carefully from the Can. CR-39 detector etched in NaOH solution with condition 6.25 N at 70 ± 1 C for 7 h. After etching CR-39 detectors were washed in distilled water and then dipped for few minutes in a 3% acetic acid solution, washed again with distilled water and finally dried (Zarrag, El-Araby, & Elhaes, 2012). In the case of LR-115 detector etched in 2.5 N of NaOH in water bath at 60 ± 1 C for about one hour. After the chemical etching LR-115 detectors were washed in distilled water and then placed in a solution of (50 ml water þ 50 ml ethyl alcohol) again washed using water and dried in air (Belafrites, 2008). After etching CR-
Fig. 1 e Plastic cylindrical container of the samples.
39 and LR-115 detectors, the tracks were counted using an optical microscope with a magnification of 640. The value of radon concentration in (Bqm3) at secular equilibrium given by the following equation: CRn ¼
r hT
(1)
Where, CRn is radon concentration (Bqm3), r is the track density (track cm2), T is the exposure time (day) and h is the calibration coefficient of CR-39 and LR-115detectors in (tracks cm2 day1/Bqm3) (Hafez, El-Farrash, & Yousef, 2011). Radon surface exhalation rate given by the relation: EA ¼
CVl A T þ 1l ðelT 1Þ
(2)
Where, EA is the surface exhalation rate in (Bqm2 h1), CRn is the radon concentration in (Bqm3 h1), l is the decay constant of radon (h1), V is the effective volume of the Can (m3), A is the area covered by the can (m2) and T is the irradiation time (Rehman et al., 2006; Barooah, Phukan, & Baruah, 2011).
3.
Results and discussion
The values of radon concentration and surface exhalation rate for phosphate samples are listed in Table 1, which represents a comparison between the values of radon concentration and surface exhalation rate which were measured using CR-39 and LR-115 detectors. In El-Sebaeya area the values of radon
Please cite this article in press as: Yousef, H. A., et al., Radon exhalation rate for phosphate rocks samples using alpha track detectors, Journal of Radiation Research and Applied Sciences (2015), http://dx.doi.org/10.1016/j.jrras.2015.09.002
66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130
JRRAS190_proof ■ 11 September 2015 ■ 3/6
3
J o u r n a l o f R a d i a t i o n R e s e a r c h a n d A p p l i e d S c i e n c e s x x x ( 2 0 1 5 ) 1 e6
Table 1 e Comparison between radon concentration and surface exhalation rate using CR-39 and LR-115 detectors. Area
No.
CR-39
LR-115
CRn (Bq m3) El-Sebaeya
EA (Bq m2 h1)
2358.03 ± 50.87 1422.51 ± 39.554 14519.82 ± 126.07 680.66 ± 27.44 34311.30 ± 193.78 17527.71 ± 138.51 12184.84 ± 115.50 4708.32 ± 71.83 29502.39 ± 179.69 9894.73 ± 104.09 12711.03 13109.42 ± 119.80 13811.88 ± 122.96 16240.96 ± 133.33 10164.99 ± 105.50 18679.88 ± 142.99 21699.81 ± 154.11 24595.00 ± 104.11 19198.94 ± 188.09 12738.94 ± 188.09 8001.80 ± 93,61 15824.16
1 2 3 4 5 6 7 8 9 10
Average Abu-Tartur
1 2 3 4 5 6 7 8 9 10
Average
2.12 1.28 13.09 0.61 30.94 15.80 10.99 4.24 26.61 8.92 11.46 11.82 12.45 14.64 9.16 16.84 19.57 22.18 17.31 11.49 7.21 14.26
concentration and surface exhalation rate using CR-39 detector ranged between (680.66 ± 27.44 to 34311.30 ± 198.78) Bqm3 and (0.61 ± 0.02 to 30.94 ± 0.17) Bqm2 h1, respectively. In the case of LR-115, the values of radon concentration and surface exhalation rate ranged between (584.60 ± 54.88 to 29496.68 ± 356.08) Bqm3 and (0.52 ± 0.04 to 26.16 ± 0.22) Bqm2 h1, respectively. In Abu-Tartur area, the values of radon concentration and surface exhalation rate using CR-39 ranged from (8001.80 ± 39.61 to 24595.00 ± 304.11) Bqm3 and (7.21 ± 0.08 to 29.18 ± 0.09) Bqm2h1, respectively. In case of LR-115 detector, the values of radon concentration and surface exhalation rate ranged from (6877.68 ± 171.94 to 21144.59 ± 302.15) Bqm3 and (6.20 ± 0.15 to 19.07 ± 0.27) Bqm2 h1, respectively. The average values of radon concentration equal 12711.03 and 10925.02 Bqm3 in El-Sebaeya area using CR-39 and LR115 detectors, respectively. Also the average values of radon
CRn (Bq m3)
± 0.04 ± 0.03 ± 0.11 ± 0.02 ± 0.17 ± 0.12 ± 0.10 ± 0.06 ± 0.61 ± 0.09
EA (Bq m2 h1)
2024.61 ± 93.28 1220.79 ± 72.44 12478.70 ± 231 584.60 ± 54.88 29496.68 ± 356.08 15066.44 ± 254.48 10471.28 ± 212.15 4044.94 ± 131.86 25361.47 ± 330.17 8502.54 ± 191.17 10925.20 11266.51 ± 220.06 11872.61 ± 225.90 13961.71 ± 325.53 8734.66 ± 193.76 16055.10 ± 262.72 18651.43 ± 283.15 21144.59 ± 302.15 16502.15 ± 266.33 10948.42 ± 216 6877.68 ± 171.94 13601.48
± 0.10 ± 0.11 ± 0.12 ± 0.09 ± 0.12 ± 0.13 ± 0.09 ± 0.13 ± 0.16 ± 0.08
1.82 ± 1.10 ± 11.25 ± 0.52 ± 26.60 ± 13.58 ± 9.44 ± 3.64 ± 22.87 ± 7.66 ± 9.84 10.16 ± 10.70 ± 12.59 ± 7.87 ± 14.48 ± 16.82 ± 19.07 ± 14.88 ± 9.87 ± 6.20 ± 12.26
0.08 0.06 0.20 0.04 0.32 0.22 0.19 0.11 0.29 0.17 0.19 0.20 0.29 0.17 0.23 0.25 0.27 0.24 0.19 0.15
concentration equal 15824.16 and 13601.48 Bqm3 for AbuTartur area using CR-39 and LR-115 detectors, respectively. From the obtained results we can conclude that the average values of radon concentration in Abu-Tartur are higher than El-Sebaeya. Fig. 2 shows the comparison between the values of radon concentration for El-Sebaeya and Abu-Tartur areas using CR-39 detectors. Sample number 5 has a high value of radon concentration, using CR-39 and LR-115 detectors. This means that the values of radon concentration high in this position due to increasing the values of uranium concentration, so that we can save costs and the dig time and concern the dig in this position because, its rich by phosphate ore. A high-grade phosphate product suitable for fertilizers and other phosphate compounds. But sample number 4 has a low value of radon concentration due to this point has a low value uranium concentration and the phosphate ore.
35000
40000
sebaiua
35000
Abu
30000
30000 C (Bqm )
CRn (Bqm-3)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
25000 20000
Sebaiua
Abu Tartur
25000 20000 15000
15000 10000
10000
5000
5000
0
0
1
2
3
4
5
6
7
8
9
Sample number
Fig. 2 e The comparison between the values of radon concentration for El-Sebaeya and Abu-Tartur areas using CR-39 detector.
1
2
3
4
5
6
7
8
9
10
Sample number
Fig. 3 e The comparison between the values of radon concentration for El-Sebaeya and Abu-Tartur areas using LR-115detector.
Please cite this article in press as: Yousef, H. A., et al., Radon exhalation rate for phosphate rocks samples using alpha track detectors, Journal of Radiation Research and Applied Sciences (2015), http://dx.doi.org/10.1016/j.jrras.2015.09.002
66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130
JRRAS190_proof ■ 11 September 2015 ■ 4/6
4
35000
E (Bqm h )
Abu Tartur
25000 20000
EA (Bqm-2h-1)
30
Sebaiua
30000
R² = 1
25 20 15
15000
10
10000
5
5000
0 0
0 2
3
4
5 6 Samples number
7
8
9
Fig. 4 e The comparison between the values of surface exhalation rate for El-Sebaeya and Abu-Tartur areas using CR-39 detector.
Also Fig. 3 shows the comparison between the values of surface exhalation rate using CR-39 detectors for El-Sebaeya and Abu-Tartur areas. From the obtained experimental results of Abu-Tartur area, sample number 7 has a high value of radon concentration, this means that the values of radon concentration high in this position due to increasing the values of uranium concentration and indicate that, it is rich by phosphate ore. But sample number 10 has a low value of radon concentration due to this point has a low value of phosphate ore. Phosphate ores are of two major geological origins, igneous and sedimentary. The composition of phosphate ores varies from one deposit to another. Therefore, phosphate rocks from different sources are expected to behave differently in acidification processes (Adel, Mohsen, Ahmed, Magdy, & Ahmed, 2013). From the results we find that the average values of radon concentration in Abu-Tartur are higher than El-Sebaeya. Fig. 4 gives the comparison between the values of radon concentration for El-Sebaeya and Abu-Tartur using LR-115 detectors. Fig. 5 shows the comparison between the values of surface exhalation rate for El-Sebaeya and Abu-Tartur areas using LR115 detectors. The correlation relation between radon concentration and surface exhalation rate using LR-115 detectors for El-Sebaeya given by Fig. 6 which equal (R2 ¼ 1). Also the correlation relation between radon concentration and surface
30
Sebaiua
5000
10000
15000
20000
25000
Abu Tartur
25 20
30000
35000
CRn (Bqm-3)
10
Fig. 6 e The correlation relation between radon concentration and surface exhalation rate for El-Sebaeya area by using LR-115 detector.
exhalation rate using LR-115 detectors for Abu-Tartur given by Fig. 7 and equal (R2 ¼ 1). It a good agreement between both measurements of radon concentration and surface exhalation rate. The correlation coefficient is linear because the values of exhalation rate depend on radon concentration since the volume of the cup, the area of the sample and decay constant of radon are the same for all samples. A positive correlation has been observed between radon concentration and the exhalation rate in phosphate samples. The radon exhalation study is important for understanding the relative contribution of the material to the total radon concentration found in the phosphate samples and helpful to study radon health hazard. The comparison between the obtained experimental results and the published data in different countries is given by Table 2. The values of radon concentrations in the phosphate are higher than the worldwide limit and the obtained results agreement with Mohamed (2012).
4.
Conclusion
This work is important to detect any harmful radiation in the surrounding environment, which, can be used as reference information to assess any changes in the radioactive
E (Bqm h )
1
EA (Bqm-2h-1)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
J o u r n a l o f R a d i a t i o n R e s e a r c h a n d A p p l i e d S c i e n c e s x x x ( 2 0 1 5 ) 1 e6
25
R² = 1 20
15
15 10
10 5
5 0
0
1
2
3
4
5 6 Sample number
7
8
9
10
Fig. 5 e The comparison between the values of surface exhalation rate for El-Sebaeya and Abu-Tartur areas using LR-115 detector.
0
5000
10000
15000
20000
2500
C
(Bqm )
Fig. 7 e The correlation relation between radon concentration and surface exhalation rate for Abu-Tartur area by using LR-115 detector.
Please cite this article in press as: Yousef, H. A., et al., Radon exhalation rate for phosphate rocks samples using alpha track detectors, Journal of Radiation Research and Applied Sciences (2015), http://dx.doi.org/10.1016/j.jrras.2015.09.002
66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130
JRRAS190_proof ■ 11 September 2015 ■ 5/6
5
J o u r n a l o f R a d i a t i o n R e s e a r c h a n d A p p l i e d S c i e n c e s x x x ( 2 0 1 5 ) 1 e6
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65
Table 2 e The comparison between the obtained results and the published data for phosphate samples in different countries. Countries Egypt Egypt Egypt (fert.) Libyan Morocco KSU India Iraq Egypt (El-Sebaeya) Egypt (Abu-Tartur)
CRn (Bqm3)
EA (Bqm2h1)
References
2440e29,000 8.90e1675.40 10.00e1244.00 59.3e949.0 66.01e70.23 58.53e145.34 277.78e13.89 13.00e1197.00 584.60e29496.68 6877.68e21144.59
4.16e26.24 0.02e4.12 0.05e2.35 0.061e0.441
Mohamed, 2012 Saad, 2008 Maged & Saad, 1998 Saad, Abdllah, & Husseein, 2013 Fahad, 2001 Zarrag et al., 2012 Kakati, 2014 Jebur et al., 2014 The present work
background level. The search for phosphate rock deposits became a global effort in the 20th century as demand for phosphate rock increased. Phosphate ores used to manufacture super phosphate fertilizer which, most commonly used in Egypt. It is manufactured from the reaction between sulfuric acid, phosphate rock and water. The values of radon concentrations ranged from 680.66 to 34311.30 Bqm3, 8001.80e24595 Bqm3 using CR-39 detector for El-Sebaeya and Abu-Tartur areas, respectively. But using LR-115 detectors were ranged from 584.60 to 29496.68 Bqm3, 6877.68e21144.59 Bqm3 for El-Sebaeya and Abu-Tartur areas, respectively. From the obtained results we find that the average values of radon concentration for Abu-Tartur area are higher than the values of radon concentration for El-Sebaeya area. The variation in the values of radon concentrations is due to the difference in the chemical composition and the geological form of the samples. The obtained results with each other of the activity concentrations of radon using CR-39 and LR-115 detectors are consistent, while the percentage of errors in CR-39 are lower than LR-115. The percentage of error is referring to the partial sensitivity of the detectors, detector material, track density, the etching and counting techniques. CR-39 detector is widely used for radon and considered as the best option to measure the outdoor radon concentration. The results of the present study shall help to determine the positions which have the highest value of radon and phosphate ores. The values of radon concentrations are higher than the range of action levels from 200 to 600 Bqm3 recommended by ICRP (1994). We conclude that the values of radon concentrations in the phosphate are higher than the worldwide limit and not safe for human, so that we must use personal protective masks to protect ourselves from inhalation radon and live far from the studied areas to minimize the exposure time of radiation. Also we must repeat the measurements to detect the variation in the concentration of radioactive radionuclides that affect the surrounding environment.
Uncited reference Q4
Bhardwaj and Gebregergs, 2013.
0.011e0.0311 0.348e0.0174 0.26e2.40 0.52e26.16 6.20e19.07
references
Adel, A. El-Z., Mohsen, M. A., Ahmed, M. A., Magdy, I. K., & Ahmed, A. El-A. (2013). Production of calcium monohydrogenphosphate from Sebaiya phosphate ore leached by nitric acid. Journal of European Chemical Bulletin, 2(10), 752e757. Ahmed, S. S. (2003). Environmental issues in the extraction of phosphate ore from Abu-Tartur mine, Egypt. The International Mining Congress and Exhibition of Turkey e IMCET. Q2 Ahmed, N. K., Abbady, A., El-Kamal, A. H., Steinhausler, F., & ElArabi, A. M. (2001). Studies of natural radioactivity of some Egyptian rock phosphates. Journal of Pure and Applied Physics, 39, 553e560. Ashraf, El M. (2012). Phosphate mining wastes at Abu-Tartur mine area, Western desert of Egypt. Australian Journal of basic and Applied Sciences, 6(10), 231e248. Ashraf, E. M. K., Higgy, R. H., & Pimpl, M. (2004). Radiological impacts of natural radioactivity in Abu-Tartur phosphate deposits, Egypt. Journal of Environmental Radioactivity, 55, 255e267. Barooah, D., Phukan, S., & Baruah, R. (2011). Study of radon exhalation rates using LR-115 (II) nuclear track detectors in coal mining area of the foothills of Mokokchung District, Nagaland. Indian Journal of Pure and Applied Physics, 49, 665e668. Belafrites A.., Natural radioactivity in geological samples from Algeria by SSNTD and gamma-ray spectrometry. IX Radiation Physics & Protection Conference, 15e19 November 2008, Nasr City, Cairo, Egypt. Bhardwaj, M. K., & Gebregergs, H. G. (2013). Measurement of radium content and radon exhalation rate in soil samples of Mekelle city, Ethiopia. International Journal of Science and Nature, 4(1), 182e184. El-Zakla, T., Abdel-Ghany, H. A., & Hassan, A. M. (2007). Natural radioactivity of some local fertilizers. Roman Journal of Physics, 52(5), 731e739. Fahad, M. (2001). Calibration LR-115 for uranium estimation and radon measurement from phosphate and coal. Physics and Chemistry News, 2, 63e65. Hafez, A. F., El-Farrash, A. H., & Yousef, H. A. (2011). Determination of radon concentration in some environmental samples using cup technique. Journal of Environmental Sciences, 40(4), 535e548. IAEA. (2003). Radiation protection against radon in workplaces other than mines. Vienna: Safety Reports Series No. 33, IAEA. ICRP. (1994). Publication (65) protection against radon-222 at home and work. Barking, Essex: UK. Elsevier Science, Ltd.
Please cite this article in press as: Yousef, H. A., et al., Radon exhalation rate for phosphate rocks samples using alpha track detectors, Journal of Radiation Research and Applied Sciences (2015), http://dx.doi.org/10.1016/j.jrras.2015.09.002
66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130
JRRAS190_proof ■ 11 September 2015 ■ 6/6
6 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
J o u r n a l o f R a d i a t i o n R e s e a r c h a n d A p p l i e d S c i e n c e s x x x ( 2 0 1 5 ) 1 e6
Jebur, J. H., & Subber, A. H. (2014). Natural radon. Exhalation rate from fertilizer used in Basra Governorate, Iraq. International of Physics and Research, 4(6), 1e10. Kakati, R. K. (2014). Radon exhalation rate of soil and indoor radon concentration of various places of Karbi Anglonge District of Assam. Journal of Applied Physics, 6(4), 13e16. Korkmaz, B., & Turgut, S. A. (2005). Research on the urea hydrolysis rate in the soil of Thrace region. Journal of Central European Agriculture, 6(2), 107e114. Maged, A. F., & Saad, E. A. (1998). Radon exhalation rate from some fertilizers, clay and potatoes in Egypt. Environmental Management and Health, 9(3), 130e135. Mansur, H. H., Per Khdar, S., Abdulla, Y. H., Muhamad, Q. N., Othman, M. N., & Qader, S. (2005). Measurement of indoor radon levels in Erbil capital by using solid state nuclear track detector. Journal of Radiation Measurement, 40, 544e547. Mohamed, A. E. (2012). An overview on studying 222Rn exhalation rate using passive technique solid state nuclear track detector. American Journal of Applied Sciences, 9(10), 1653e1659. Ramadan, M. R. (2012). Measurement of radon concentration in Iraqi and imported cement. Journal of Thi-Qar Science, 3(2), 63e69.
Rehman, S., Imtiaz, N., Faheem, M., & Matiullah. (2006). Determination of 238U contents in ore samples using CR-39 based radon dosimeter disequilibrium case. Journal of Radiation Measurements, 41, 471e476. Saad, A. F. (2008). Radium activity and radon exhalation rate from phosphate ores using CR-39 online with on electronic radon analyzer Alpha GUARD. Journal of Radiation Measurements, 43, 463e466. Saad, A. F., Abdllah, R. M., & Husseein, N. A. (2013). Radon exhalation from Libyan soil samples measured with the SSNTD technique. Journal of Applied Radiation and Isotopes, 72, 163e168. UNSCEAR. (1993). Sources and effects of ionizing radiation. United Nations Scientific Committee on the Effects of Atomic Radiation. Report to the General Assembly. WHO. (2009). Handbook on indoor Radon, A public health perspective. World Health Organization. Zarrag, A., El-Araby, E. H., & Elhaes, H. (2012). Monitoring of radon concentration in Jazan beach soil. Journal of Applied Sciences Research, 8(2), 823e827. Q3
Please cite this article in press as: Yousef, H. A., et al., Radon exhalation rate for phosphate rocks samples using alpha track detectors, Journal of Radiation Research and Applied Sciences (2015), http://dx.doi.org/10.1016/j.jrras.2015.09.002
22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42