Jpn. J. Health Phys., 40 (2), 191-201 (2005)

Report

Radioactivity in Drinking Water of

Shymal Ranjan CHAKRABORTY, *1 Abdus Sattar MOLLAH, *2, *3 Aleya BEGUM*2 and Gias Uddin AHMAD*4

(Received on August 17, 2004) (Accepted on February 21, 2005)

The activity concentration levels of 232Th, 238U,40K and 137Csin drinking water of different locations of Bangladesh were measured by using a high purity germanium (HPGe) detector. The average activity levels with one standard deviation (lcr) of 232Th, 238Uand 40K were found to be 250+ 52 mBq/L-1, 157+30 mBq/L-1 and 9 + 3 Bq/L-1, respectively. The 137Cswas detected only in 32% samples with an average 4 +0.8 Bq/L-1. A good correlation between the activities of 232Thand 238Uwas found. The radium equivalent activity (Raeq) and the representative level index (Iyr) due to natural radionuclides were also calculated. The average Raeq was found to be 1,212+303 mBq/L-1 and the average Iyrwas found to be 10+3 mBq/L-1. The annual individual committed effective dose (HE) due to intake of radionuclides in water was also evaluated and the average value was found to be 74+21,iSv. The distribution of radionuclides was found to be normal except 137Cs.The radioactivity levels of these radionuclides were comparable to the corresponding reported values of drinking water of different countries. The results presented in this study may helpful in establishing a regulatory limit on radioactivity in drinking water in Bangladesh.

KEY WORDS : drinking water, radioactivity of 232Th, 238U,40K and 137Cs,radium equivalent activity (Raeq), representative level index (Iyr), intake, committed effective dose, Bangladesh.

such as 137Cs,90Sr, etc. if introduced into the environment, will I INTRODUCTION eventually reach humans via the food chain. Thus, artificial ra- Man is always exposed to natural radiation as well as artifi- dionuclide like 137Cs(T1/2 = 30.2 years) may contribute to the cial radiation sources. The radiation dose may be imparted to radiation dose that human receive from all sources. Caesi- body both internally and externally. The internal exposure is due um-137, which has chemical properties similar to potassium, to the intake of radionuclides through ingestion of contaminated distributes itself within the living cells in the same way as po- food and drinks, which are inextricably associated with food- tassium and is found mostly in the muscle. stuffs and drinks;and inhalation of contaminated air.The average Bangladesh is located at 880l' E - 9241' E longitude and at annual effective dose to adults from natural sources of ionizing latitude 2034' N - 2638' N having comparatively high popula- radiation is 2.4 mSv.1) tion density. Its geographical situation is downward to . The terrestrial natural radiations are emitted due to the pres- Most of the rivers of Bangladesh have been originated from the ence of four radioactive decay series namely: uranium, thorium, hill tracts of India, Nepal, and Bhutan ; and flown through the actinium, and neptunium and some other non-series single ra- land of India. Therefore, its land (and consequently the ground dioisotopes, such as: 87Rb, 40K, 14Cand 3H in nature. Of these, water) might be contaminated by radioactive sources from up- the major contributions are from 232Th,238U and 40K. Soil, sand stream. and rock ; and consequently, the ground water contain a small As an aftermath of Chernobyl accident, the radioactivity lev- quantity of these elements. The internal dose from worldwide els in drinking water have been measured in different countries fallout is due to fission products that enter the human body of the world. In Bangladesh, no systematic countrywide data through drinks and other foodstuffs. Man-made radionuclides are available on radioactivity in water. Studies and surveys of environmental radioactivity are of great importance and interest * 1 Department of Physics , University of Chittagong, Chittagong-4331, in health physics not only for many practical reasons but also for Bangladesh. more fundamental scientific reasons. It is therefore necessary to *2 Bangladesh Atomic Energy Commission, 4 Kazi Nazrul Islam Av- enue, P. 0. Box 158, Ramna, Dhaka-1000, Bangladesh. know the present level of radioactivity in drinking water of Ban- *3 Correspondence author ; E-mail : asmollah@dhaka. agni. corn gladesh. In this context, a study was undertaken to measure the *4 Department of Physics, Bangladesh University of Engineering & radioactivity levels due to natural occurring and man-made ra- Technology, Dhaka-1000, Bangladesh. dionuclides in drinking water of 56 different locations of Ban- 192 Shymal Ranjan CHAKRABORTY, Abdus Sattar MoLLAH, Aleya BEGUM and Gias Uddin AHMAD gladesh. The results presented in this study may helpful in es- The crow-flight distance between two adjacent locations was tablishing a regulatory limit on radioactivity in drinking water in below 80 km. These 56 locations covered the entire geographical Bangladesh. area of Bangladesh. In each of the spot, community-based drinking water samples were collected for radioactivity assess- II MATERIALS AND METHODS ment. All of the field works were performed during the period In order to assess the radioactivity levels in drinking water January 1998-June 1998. The climate of Bangladesh is tropi- and consequent radiation dose level in Bangladesh, 56 sample cal, warm and wet, with rainy (approximately May- September) collecting spot as shown in Fig. 1, was selected by considering and dry (approximately October-April) seasons. The maximum the population density, area, and the communication system (s). rainfall is about 450 mm.

Location 01. Akhaura (Brahminbaria) 02. Srimangal (Maulavibazar) 03. Sunamgonj 04. (Goainghat, ) 05. Comilla 06. Chandpur 07. Feni 08. Noakhali 09. Hatiya (Noal hali) 10. Sandweep (Chittagong) 11. Dinajpur 12. Syedpur (Nilphamari) 13. Panchagarh 14. Rangpur 15. Gaibandha 16. Kurigram 17. Bogra 18. Ullapara (Sirajgonj) 19. Natore 20. Rajshahi 21. Nachole (Chapai Nawabgonj) 22. Kushtia 23. Faridpur 24. Gopalgonj 25. Jessore 26. Shyamnagar (Satkhira) 27. Khulna 28. Borguna 29. Shariatpur 30. Chorfashion (Bhola) 31. Barisal 32. Mymensingh 33. Kishoregonj 34. Jhenaigati (Sherpur) 35. Barhatta (Netrakona) 36. Kalihati (Tangail) 37. Aricha (Shibalaya, Manikgonj) 38. Munsiganj 39. Narsingdi 40. Teknaf (fox's Bazar) 41. Cox's Bazar 42. Roangchheri (Bandarban) 43. Chittagong 44. Khagrachheri 45. Rangamati 46. Roop Pur (Ishwardi, Pabna) 47. Chuadanga 48. Kuakata (Khepupara, Potuakhali) 49. Pirojpur 50. Badalgachhi (Naogaon) 51. Laksbmipur 52. Nabigonj (Habigonj) 53. Sripur (Gazipur) 54. Ashulia (Savar, Dhaka) 55. Sonargaon(Narayangonj) 56. BUET (Dhaka)

Fig. 1 Map of Bangladesh showing different locations of sample collection. Radioactivity in Drinking Water of Bangladesh 193

1. Sample Collection per second corresponding to the energy of 1,460.75 keV emitted From each of the pre-selected 56 sampling stations, drinking from 40K (10.70%) ; and counts per second corresponding to the water samples were collected. In every spot, a community- energy 661.66 keV emitted from 137Cs (85.21%) were consid- tubewell or any other community based water supply system ered. After determination of the integral counts under the gam- like municipality water supply was selected from where most of ma energy peaks of interest the specific gamma activities of the the people collected their drinking water. In Jaflong (Sylhet) individual samples for specific radionuclide were then calcu- where many people use the water of Jaflong-river (Piyain river), lated by employing the formula3 two samples were collected; one from a tubewell and the other A= from Piyain-river. The water sample from the lake nearby Ran- s(E)clXV (1) gamati town was collected as it represents the drinking water of Y where, A is the activity of the sample in Bq/L-1, C is the peak Rangamati's people. In all cases, 1.2 L of water was collected area counts in CPS, e (E) is the efficiency of the detector at and packed within air-tight plastic bottles to avoid any leakage energy E (keV), I is the photon emission probability at energy and spillage. An individual identification mark was given on E (keV), and Vis the volume of water samples in litre (L). Then each of the water sample bottle by non-erasable markers. by different calculations, the activities of the radionuclides 2. Sample Preparation 212Pb, 208T1, 228Ac, 214Pb, 214Bi, 40K and 137Cs; and ultimately, Water samples were measured by measuring flask and 1 L of the activities of 232Th, 238U, 40K and 137Cs in each of the water water from each of the collected sample was poured into the Ma- sample were calculated. The 232Thactivity was found by aver- rinelli beakers and sealeddair-tightly. The sealed water samples aging the activity of 212Pb, 3 times activity of 208T1,and the ac- were allowed to attain the radioactive secular equilibrium be- tivity of 228Ac. The activity of 238Uin each sample was found tween the gaseous (222Rnand 22oRn) and non-gaseous radioac- out by averaging the activities of 214Pb, calculated from 609.31 tive decay products (of the natural radioactive serieses) with keV and 214Bicalculated from 1,120.29 keV photo peak. The their respective parents and daughters by preserving them in an activities of 40Kand 137Cswere obtained by direct measurement airtight condition for 28 days. 2) All sample preparation and from single energy photopeak 1,460.75 keV and 661.66 keV re- measurements were carried out at the Radiation Control and spectively. Waste Management Division, Institute of Nuclear Science and The statistical fluctuations in the readings were considered by Technology, Atomic Energy Research Establishment, Gana- using standard formulas and method. 4-6) In the present study, kbari, Savar, Dhaka. +16 of all the measurements were considered as it covers 68% 3. Equipment Setup of most probable values. The radioactivity measurement was carried out by employing The effective dose due to intake of radionuclides through an HPGe detector of relative efficiency 22% and energy reso- water for each of the sampling location were calculated by using lution (FWHM) 2.12 keV for the 1,332 keV of 60Co (supplied the conversion factors. 1) by SILENA Detektor System GmbH, Germany) with necessary 4. Statistical Analysis electronic accessories interfaced. The HPGe detector was cali- 4.1 Frequency distribution brated at different 7-ray energy to find out the efficiencies at any Frequency distribution of the concentrations of the radionu- required energy by employing standard procedure. 3) clides 232Th, 238U,40K and 137Cswere also done. The distribu- After establishment of the secular equilibrium and after com- tions were plotted by classes of the concentrations of a radionu- pletion of necessary measurements and quality assurance of the clide as abscissa and the corresponding frequencies as ordinate. HPGe detector, the samples were read out. The reading out pe- 4.2 Cumulative percent plot riod for each of the water samples was 30,000 sec. Before and The tool "the cumulative percent plot" or simply "the prob- after a set of readout of samples, background reading of the de- ability plot" helped to determine the geometric mean (GM) and tector was taken by placing an empty Marinelli beaker on the the geometric standard deviation (GSD) of the concentration of detector head. The mean background reading from a set of mea- individual radionuclides. To draw the cumulative frequency plot surement was subtracted from each of the sample reading. (probability plot) for a data containing a number of entries, the The gamma energy peaks at 238.63 keV, 351.92 keV, 583.19 entries were ranked at first by arranging them in ascending order keV, 609.31 keV, 911.07 keV, 1,120.29 keV, and 1,460.75 keV and then the cumulative percents were calculated by using the were clearly identified in samples spectra. For few of the sam- formulas) : ples a 7-ray energy peak at 661.66 keV was also identified. Cumulative Percent =100(i-0.5) (2) These energy peaks were used for the estimation of activity con- centration levels for the corresponding radionuclides. n where,i' is the serial position and n' is the total number of In the present study, the counts per second corresponding to entries. In the present study, cumulative frequency plots were the energies ofthe emitted photons 238.63 keV, 583.19 keV and drawn for average concentrations of 232Th, 238U,40K and 137Cs 911.07 keV of the radionuclides 212Pb (44.60%), 208T1(85.77%), found in water collected from different locations of Bangladesh. and 228Ac (27.70%) respectively within the decay chain of From each of the plot, corresponding GM and GSD were deter- 232Th; the counts per second corresponding to the energies of mined and noted, and finally compared with their respective AM the emitted photons 351.92 keV, 609.31 keV and 1,120.29 keV (arithmetic mean) and SD (standard deviation). of the radionuclides 214Pb(38.90%), 214Bi (43.30%) and 214Bi (15.70%) respectively within the decay chain of 238U; counts 194 Shymal Ranjan CHAKRABORTY, Abdus Sattar MoLLAH, Aleya BEGUM and Gias Uddin AHMAD

Table 1 Results of radioactivity, radium equivalent activity and level index in water samples.

* ND=Not Detected. Radioactivity in Drinking Water of Bangladesh 195

and the GSD of 137Cs in water samples were found to be 3.6 III RESULTS AND DISCUSSION Bq/L-1 and 1.3 Bq/L-1 respectively. The activity concentration levels of the 232Th, 238U,40K and The correlation coefficients between the concentrations of 137Csin water samples were determined by following the stand- radionuclides 232Th,238U, 40K and 137Csfound in water samples ard procedure. The detailed results are given in the Table 1. were calculated by MS Excel sheet. The details of the results are The average concentration of 232Thin water samples collected shown in Table 3. A good correlation was found between 232Th from 56 different locations was found to be 250+52 mBq/L-1 and 238U (r = 0.83) concentration levels and very poor cone- ranging between 109+30 and 365+45 mBq/L-1. The lowest and lation between all other combinations having the poorest cone- highest concentrations were found in water samples of Nabigonj lation (r = 0.01) between 232Thand 137Csconcentration levels. (in Habigonj district) and Kurigram respectively as shown in The frequency distributions of the activity concentrations of Table 2. The GM and GSD were found to be 250 mBq/L-1 and 232Th, 238U, 40K and 137Csare shown in Figs. 2 (a), 3 (a), 1.2 respectively. The range of the concentration of 238U was 4 (a), 5 (a). Figures 2 (a), 3 (a), 4 (a), 5 (a) also show the found to be 83+28 to 230+33 mBq/L-1 with an average 157+ fits made to the empirical frequency distributions, taking into 30 mBq/L-1. The highest and the lowest concentrations of 238U account the values obtained for skewness and kurtosis coeffi- were found in the samples of Dinajpur and Jhenaigati (Sherpur cient. Thus, the activities corresponding to 232Th238U, 40K and district) respectively as shown in Table 2. The GM and GSD of 137Csare fitted to a normal distribution. The evaluation of these 238Uwere found tobe 157mBq/L-1 and 1.1 respectively.The average fits is carried out using the x2 test at a 0.05 significance level. activity concentration of 40Kwas found to be 9+3 Bq/L-1. This As a result of this test, the hypothesis of normal distribution for average concentration was ranged between 3+1.1 and 17+1.2 232Th, 238U, 40K and 137Cs cannot be rejected. Moreover,very the Bq/L-1. The highest concentration of 40Kwas found in the water close similarity of the arithmetic and geometric average specific sample of Khulna and the lowest concentration of the same ra- activities of these radionuclides in water samples indicates dionuclide was found in the water sample of Nabigonj (shown statistical normal distribution. in Table 2). The GM and the GSD of the concentrations of the Figures 2(b), 3(b), 4(b), 5(b) show the observed cumulative mentioned radionuclide in the assessed water samples were frequency distributions for 238U,232Th, 40Kand 137Csconcen- found to be 9 Bq/L-1 and 1.4 Bq/L-1 respectively. Out of the 57 trations in water, obtained with surface-weighted cumulative water samples collected from 56 different locations of Ban- percentages from individual measurements made in the different gladesh, the 137Csradionuclide was detected only in 18 samples locations of the country. Solid lines represent the cumulative (32%). The range of the activity of the mentioned radionuclide frequencies expected under the assumption of lognormal dis- in the said number of samples was found to be from 2.2+1.4 to tribution. The parameters GNM and GSD used to construct these 5.4+1.6 Bq/L-1. The lowest and the highest activities of 137Cs lines are the respective nationwide GM and GSD estimates were found in the water samples of Rangamati and Jaflong (in given in Table 2. These figures show that the observed distribu- ) respectively. The highest concentration of 137Cs tions of concentrations of 238U, 232Th, 40K and 137Cs in water found in water sample collected from a tubewell of Jaflong is can be adequately approximated by a normal distribution. consistent with the highest activity level of 137Csfound in the The results summarized in Table 4 show that, in general, the soil sample measured by Chakraborty. 6) By considering the concentrations of 238U, 232Th and 40K in water are higher than zero concentration of 137Csin 39 samples, the average activity the world figures reported by UNSCEAR. Table 4 shows in de- concentration level was found to be 3.7+0.8 Bq/L-1. The GM tail the concentration of different radionuclides in some of the

Table 2 The range and average activities of radionuclides in water samples.

*1 These minimum activities are the corresponding minimum activities detected above the MDC (ignoring all ND activities). In calculating the average values, all ND values were assumed to zero.

Table 3 The correlation coefficients between the concentrations of radionuclides. 196 Shymal Ranjan CHAKRABORTY, Abdus Sattar MoLLAH, Aleya BEGUM and Gias Uddin AHMAD

Concentration (mBq/L) Concentration (mBq/L) (a) (b) Fig. 2 (a) Frequency distribution of 232Thconcentrations in water. (b) Probability plot (cumulative frequency plot) for 232Thcon- centrations in water.

Concentration (mBq/L) Concentration (mBq/L) (a) (b) Fig. 3 (a) Frequency distribution of 238Uconcentrations in water. (b) Probability plot (cumulative frequency plot) for 238Ucon- centrations in water. Radioactivity in Drinking Water of Bangladesh 197

Concentration (mBq/L) Concentration (mBq/L) (a) (b) Fig. 4 (a) Frequency distribution of 40K concentrations in water. (b) Probability plot (cumulative frequency plot) for 40K con- centrations in water.

Concentration (mBq/L) Concentration (mBq/L) (a) (b) Fig. 5 (a) Frequency distribution of 137Csconcentrations in water. (b) Probability plot (cumulative frequency plot) for 137Cscon- centrations in water. 198 Shymal Ranjan CnAKRABORTY, Abdus Sattar MOLLAH, Aleya BEGUM and Gias Uddin AHMAD

Table 4 Comparison of data on average radioactivity in drinking water in different countries of the world.

* 1 Name of radioisotope given in parenthesis indicates the isotope on/for which measurement had been done in the corresponding decay chain. *2 NA = Not Available. *3 Data given in parenthesis indicates range. countries of the world9-21). YU and MAo21)observed 232Thin calculated according to7) as the drinking water of Hong Kong. The concentration was 7. 1 Raeq-CRa + (10/7) CTh+ (10/130) CK (3) mBq/L. In the present findings 232Thactivity in the drinking where CRa, CTh, and CKare the activity concentrations of 226Ra, water is comparatively higher than the results from other 232Th and 40Kin mBq/L-1, respectively. Since 226Raand 238U workers. The observed 40K in drinking water of Hong Kong were in secular equilibrium during reading out period, the were 0. 11 Bq/L, but concentrations found in this study are activity of 238U was assumed to be equal to the activity of slightly higher. The results of this study are comparable to the 226Ra. Another radiation hazard index called the representa- corresponding level found in the water sample of India; higher tive level index (In) which, is defined as follows than those of Finland, North Carolina, and Taiwan; and lower Iyr= (1/150) CRa+ (1/100) CTh+ (1/1500) CK (4) than those of Iowa and Saudi Arabia; as shown in Table 4. The where, CRa, Cm and CKare the same as defined earlier; Iyrwere various geological characteristics of these areas are the main calculated for each of the samples using Equation (4). cause for such a wide range of concentration found in the under- The radium equivalent activity and representative index level ground water. This also may be due to the type of soil, sand- were only due to natural radionuclides 232Th,238U and 40K. The stone, gravel and clay and it is dependent on the depth of the concentration of anthropogenic radionuclide 137Cs found in well. The differences between our results and those of others)) many samples was not taken into account in these regards. The may also indicate the significant role of the ecosystems in the ra- Raeq was found to be ranged between 1,859 mBq/L-1 and 481 dionuclides resuspension. mBq/L-1 having an average 1,212 + 303 mBq/L-1 (Table 1). 1. Radium Equivalent Activities and the Representative The highest Raeq is found in the water sample of Rangpur and Level Indexes the lowest Raeq concentration being found in the sample of Levels of hazards due to the natural radioisotopes (232Th,238U Nabigonj. The highest Representative Level Index (Iyr) 15.9 and 40K) found in water samples were calculated. Two indices mBq/L 1 was found in the water sample of Rangpur, while the were employed in this regard. These are radium equivalent act- lowest Iyr 3. 7 mBq/L-1 found in the water of Nabigonj. The ivity (Raeq), and representative level index (Iyr). These two Representative Level Index varied having an average 9.6 + 2. 5 indices simply denote the levels of hazard due to natural radio- mBq/L-1. active nuclei and help to compare the hazard levels of different 2. Radiation Dose Due to Intake of Water samples. The most widely used radiation hazard index Raeqwas Radiation doses received due to the intake of water through- Radioactivity in Drinking Water of Bangladesh 199

Table 5 Average committed effective dose (HE) based on ingestion of 232Th, 238U,40K and 137Cs in 1 L drinking water and it)s consequent annual effective dose equivalent to individual.

* Annual Committed Effective Dose is estimated on the assumption that an adult person of Bangladesh intake 2 L water per day in an average (730 L/y). out Bangladesh were calculated by employing the conversion total contribution of these radionuclides does not exceed the coefficients given in ICRP Publ. 68. 8) The average value of the worldwide average effective dose due to ingestion and inhala- annual radiation dose received by an adult in Bangladesh tion of terrestrial radionuclides of 230, uSv. 1) The mean annual through water intake was found to be 74 + 21pSv by consider- dose equivalent to the Bangladeshi population from the intake ing an adult intake of 730 L water per year, the range of which of water is 74pSv, and the average annual collective dose equiva- was found to vary from 24 + 6 to 134 + 16 pSv/y-1 (shown in lent is N9100 person/Sv. The results reported here for the na- Table 5). The lowest dose was found for the people of Nabigonj tional survey of natural radioactivity in water in Bangladesh, the (covering the district Habigonj)while the highest dose was foun- only current data referring to the whole country, represent a basic d for the people of Sunamgonj. This dose level is slightly higher data set for the assessment of dose to the Bangladeshi popula- than the dose level estimated in US (range 2- 50,uSv/y-1). 9) The tion due to intake of water. They also provide a valuable and GM and the GSD values of the radiation dose received due to in- useful reference for the design and development of specific re- take of drinking water by the people throughout Bangladesh gional surveys related to the measurement of radon in those were found to be 74pSv/yyl and 1.3, uSv/y-1 respectively. These areas showing enhanced levels of natural radioactivity. were estimated from the corresponding cumulative frequency IV CONCLUSION plots as shown in Fig. 6. The proximity of the arithmetic and GM dose levels indicates the normal distribution of dose levels High resolution HPGe gamma-ray detector was used to deter- and the distribution of radionuclides in a broad sense. mine activity concentration and the resulting ingestion doses From the present results, it can be assumed that the effective due to 232Th, 238U, 40K and 137Cs. The concentration levels of dose (for ingestion) due to intake of drinking water from the radionuclides in water samples were found to be somewhat 200 Shymal Ranjan CHAKRABORTY, Abdus Sattar MoLLAH, Aleya BEGUM and Gias Uddin AHMAD

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surement of radioactivity in Arizona ground water using Abdus Sattar MOLLAH improved analytical techniques for samples with high Dr. Abdus Sattar MOLLAHwas born in Mun- dissolved solids, Health Phys., 68 (2), 185-194 (1995). shigonj, Bangladesh in 1954. He completed 20) Y. Kuo, S. C. C. L u and V. LIN;Activity concentrations the M. Se. in Physics from Dhaka University. and population dose from Radium-226 in food and drinking He received his M. Phil. and Ph. D. degrees water in Taiwan, Int. J. Appl. Radiat. Isot., 48 (9), 1245- in Physics from BUET. He joined as a Scien- 1249 (1997). tific Officer in the Health Physics and Radia- 21) K. N. Yu and S. Y. MAO; Application of high resolution tion Protection Division of Institute of Nu- gamma ray spectrometry in measuring radioactivities in clear Science and Technology, Bangladesh Atomic Energy drinks in Hong Kong, Appl. Radiat. Isot., 45 (10), 1031- Commission (BAEC) in 1980. He has authored or co-authored 1034 (1994). more than 110 peer reviewed international and national journals in the field of health physics, radiation protection, medical phys- ics, radioactive waste management and regulatory control. At present, he is working as a Director ofNuclear Safety and Radia- tion Control Division of BAEC. His areas of research are Health Shyamal Ranjan CHAKRABORTY Physics, Medical Physics, Radioactive Waste Management and Mr. Shyamal Ranjan CHAKRABORTYwas born Regulatory Control. in Bangladesh on November 14, 1969. He re- ceived his B. Sc. and M. Se. in Physics from Aleya BEGUns Chittagong University. He also received his Dr. Aleya BEGUM was born in Dhaka, Ban- M. Phil. degree in Physics from Bangladesh gladesh in 1959. She received her B. Sc. and University of Engineering and Technology. M. Sc. in Physics from Dhaka University. He joined Bangladesh Atomic Energy Com- She also received her M. Phil. and Ph. D. de- mission as a Scientific Officer in 1998. He is teaching physics grees in Physics from Bangladesh University in the Department of Physics, Chittagong University since 1999. of Engineering and Technology. She joined His area of research is Medical Physics. Bangladesh Atomic Energy Commission as a Scientific Officer in 1983. She is working as Principal Scientific Officer in the Health Physics Division, Atomic Energy Centre of BAEC. She is also working as a Radiation Control Officer for the Atomic Energy Centre, Dhaka. Her area of research is Health Physics and Radiation Protection.