Abstract
Abstract: The activity concentrations of 238U, 232Th and 40K have been determined for solid, liquid and product (urea) samples collected from the Chittagong Urea Fertilizer Limited (CUFL), Chittagong, Bangladesh. A total of 15 samples of different kinds were analyzed by using a calibrated high purity germanium (HpGe) detector of relative efficiency of 38%. For solid samples, the mean activity concentrations of 238U, 232Th and 40K have been found 78.67±2.87, 59.74±2.27 and 463.71±9.16 Bq/Kg, respectively. The mean activity concentrations of product samples for the corresponding radionuclide were 73.12±2.83, 74.59±2.32 and 391.58±9.38 Bq/Kg, respectively. For the case of liquid samples, the mean activity concentrations for the same nuclides were 25.09±1.71, 11.34±1.55 and 39.59±1.49 Bq/Kg, respectively. The artificial radionuclide 137Cs was not detected in any of the samples. The mean radiological hazard parameter values of outdoor absorbed dose rate, indoor absorbed dose rate, external radiation hazard, internal radiation hazard, annual effective dose equivalent, radium equivalent activity and representative level index were 95.72±9.04, 114.32±9.11 nGyh-1, 0.530±.05, 0.7±50.05, 113.59±11.41μSvy-1, 199.80±17.41 and 1.390±.14 Bq/Kg respectively, in solid samples. For the product samples, the mean values of the corresponding radiological indices were 97.10+9.71, 117.56+10.32 nGyh-1, 0.57±0.05 , 0.76±0.06, 119.50 ±11.72μSvy-1 , 209.50±17.72 and 1.50±0.14 Bq/Kg, respectively. Also in the liquid samples, the mean values for the corresponding radiological parameters were 18.43±2.69, 22.13±2.77 nGy.h−1, 0.12±0.03 , 0.19±0.05, 23.59± 2.36 μSvy1, 43.65±3.54 and 0.32±0.03 Bq/Kg, respectively. The obtained results of this study show that for some samples the values are lower and for the remaining are higher than the World average values. The mean representative index value is less than unity which confirms that the area is safe for the factory workers and the public nearby. The results can be used as a baseline data for further researchers.References
Tzortzis M, Svoukis E and Tsertos H. A comprehensive study of natural gamma radioactivity levels and associated dose rates from surface soils in Cyprus. J Radiant Prot Dosim 2001; 109: 217-224. https://doi.org/10.1093/rpd/nch300
Bozkurt A, Yorulmaz N, Kam E, Karahan G and Osmanlioglu AE. Assessment of environmental radioactivity for Sanliurfa region of southeastern Turkey. Rodiat Meas 2007.
Kannan V, Rajan MP, Lyengar MA and Ramesh R. Distribution of natural and anthropogenic rodionuelides in soil and beachsand Samples of Kalpakkam (India). Appl Rodiat Isot 2002; 57: 109-119. https://doi.org/10.1016/S0969-8043(01)00262-7
Rani A and Singh S. Natural radioactivity levels in soil samples from some areas of Himachal Pradesh India using γ-ray spectrometry. Atoms Environ 2005; 39: 6306-6314. https://doi.org/10.1016/j.atmosenv.2005.07.050
Beretka J and Mathew PJ. Natural radioactivity of Australian buildings, materials, industrial wastes and byproducts. J of Health Phys 1985; 48: 87-95. https://doi.org/10.1097/00004032-198501000-00007
Samad MA. Investigation on radioactivity concentrations of the wastes generated from the fertilizer factories and study of the radiological impact of fertilizers on the soil in Bangladesh, Ph.D. thesis, Department of Physics, Jahangirnagar University, Savar, Dhaka 2007.
Alam MN, Chowdhury MI, Kamal M, Ghose S, Banu H and Chakraborty D. Radioactivity in chemical fertilizers used in Bangladesh. Appl Radiat and Isot 1997; 48: 1165-1168. https://doi.org/10.1016/S0969-8043(97)00019-5
FEMA (European Forum of Medical Association). Production of Urea and Urea Ammonium Nitrate, Booklet 2000; 5.
IAEA Technical Report. Measurement of Radionuclides in Food and the Environment, Vienna, Austria 1989; No. 295.
Fraunfelder H and Steffen RM. Alpha, Beta and Gamma-ray Spectroscopy, ed. By K. Siegbahan) 1968; 2: 997-1198.
Debertin K and Helmer RG. Gamma nand x-ray speetrometry detectiors, North Holland 1988.
Islam MN, Alam MN, Mustafa MN, Siddiqua N, Miah MMH, Shaha SL, et al. Characteristics of a shielding arrangement for a HPGe detector designed and fabricated locally. Chittagong University Studies, Part II, Sci 1990; 14(2): 105-111.
United Nations Scientific Committee of the effect of Atomic Radiation (UNSCEAR) 2000: Sources and Effects of Ionizing Radiation. Report on General assembly, United Nations, New York.
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
Copyright (c) 2016 M.M. Haque; M.M.H. Miah, Masud Kamal, A.K.M. Saiful Islam