Estimation of Radiation at Thengaipattinam of Kanyakumari District, Tamilnadu
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IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 ESTIMATION OF RADIATION AT THENGAIPATTINAM OF KANYAKUMARI DISTRICT, TAMILNADU V.Sarojini1, A.Tamil Selvi2, T.Chithambarathanu3 1Assistant Professor, Lekshmipuram College of Arts and Science, Neyyoor-629802, Tamil Nadu, India 2Associate Professor, Lekshmipuram College of Arts and Science, Neyyoor-629802, Tamil Nadu, India 3Associate Professor, S.T.Hindu College , Nagercoil- 629001, Tamil Nadu, India Abstract Baseline activity concentration of the natural radioactive nuclides in soil, drinking water, vegetable and fish found at Thengaipattinam was determined. Measurements were carried out using a NaI based Gamma ray spectrometer, alpha counting system and beta counting system. Results of the gamma ray spectrometric measurements carried out for natural radioactivity 226 232 40 levels due to Ra. Th and K in soil, drinking water, vegetable and fish specimen collected from the Thengaipattinam coast of Kanyakumari district. These studies were carried out in the Health Physics unit of BARC located in the campus of Indian Rare Earths Limited, Manavalakurichy in Tamilnadu. Alpha activity was found to be higher in soil with 27546 Bq/Kg than in water 0.0065 Bq/l and 91.02 Bq/Kg, 115.72 Bq/Kg in vegetable and fish. The beta activity estimated was 94718.23 Bq/Kg, 0.032Bq/l,220Bq/Kg and 302.15Bq/Kg in soil water ,vegetable and fish respectively. Radioactive nuclides estimation reveals that 228Ac concentration was higher in soil 2893Bq/Kg and potassium activity was rich in fish .232Th activity was also high in soil. The results of these studies are presented and discussed in this paper in detail. Key words: Radioactive nuclide, Soil, Water, Vegetable. --------------------------------------------------------------------***---------------------------------------------------------------------- 1. INTRODUCTION balanced human diet. Since it is a naturally high background radiation area fish in Thengaipattinam coast Exposure to ionizing radiation from natural sources is a may be subjected to direct and indirect contamination of continuous and unavoidable feature of life on Earth. Uranium nuclides. Radium of Uranium and Thorium series Natural radioactive nuclides exist ubiquitously in the concentrate generally at a greater level than Uranium or environment and contribute significantly to external and Thorium by about two orders of magnitude [5]. internal dose to the population[1]. Ilmenite rich beach sand Radionuclides may enter the human body at a deposits occur in the coastal stretches of Kerala, Tamilnadu, considerable smaller dose from fish mainly by intake [6]. Andhrapradesh, Orissa and Maharashtra which contain 232 238 Reproductive stages and growing tissues are the most monazite bearing black sands[2]. Th and U are sensitive to radioactivity. Radioactive isotopes can be bio reported from these regions caused mainly due to the accumulated both in primary producers and by uptake monazite bearing black sands[3]. The major sources through the food chain. The lowest dose rate at which responsible for exposure are naturally occurring 232 238 40 effects of chronic radiant exposure on fertility of aquatic radionuclides in the earth’s crust such as Th, U, K invertebrates and fish were demonstrated was about 0.25 in which occur in minerals such as monazites and zircons. Gy/hr. In sense of lives health and environmental Radionuclides belonging to the uranium (226Ra) and thorium 228 pollution, determination of the radioactivity concentration series ( Ra) enter the human body at a considerable in fish is useful because it is used for eating. Knowledge smaller dose mainly by ingestion and inhalation[4]. The of the concentration of radioactivity levels obtained can most important terrestrial sources of natural back ground 40 238 232 serve as a reference baseline value and helps to calculate radiation are K, U and Th decay series. The radium of the effective dose to population. Therefore an attempt is the uranium and thorium series concentrate generally at a made in the present investigation to studies on the natural greater level than uranium or thorium by about two orders of radioactivity content in soil, water, vegetable and fish magnitude[5] and was generally expected to accumulate collected from Thengaipattinam coastal region of more and it will reveal the concentrations of their parent’s Kanyakumari district in Tamilnadu, India. uranium and thorium. Study Area Radioactivity present in water is mainly due to the presence of radioactive elements in the earth’s crust[6]. In the sense Study area is mainly the Thengaipattinam coastal region of lives, health and environmental pollution determination which is a Naturally High Background Radiation Area of the radioactivity concentration in water is a useful (NHBRA) in the Southwest coastal region of Kanyakumari because it is used for drinking. Fish is necessary for a district in Tamilnadu, India. _______________________________________________________________________________________ Volume: 04 Issue: 12 | Dec-2015, Available @ http://www.ijret.org 188 IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 Fig. 1. Map of the Sampling stations Materials and methods: Fish Soil sample: About one kilogram of soil sample from the About 2kg of Engraulis species collected from sampling site is taken and dried in an oven at a temperature Thengaipattinam coast was taken and washed thoroughly of 1500c for 4 hours. The sample is powdered with the help with distilled water repeatedly for two or three times. of agate mortar. The powdered sample is ready for The collected species were dried by placing it in hot air radioactive analysis. Alpha and beta present in the sample o oven at a temperature of 150 C for four hours. The was determined using alpha and beta counting system and sample was then cooled and powdered. The powdered the radioactive nuclides were estimated using gamma ray sample is ready for analysis. About 0.02gm to 0.04 gm spectrometer. of powdered sample was taken in a previously cleaned aluminium planchet and alpha and beta radiation Water sample: 10l of bore water from the sampling site is present in the sample was estimated by placing it in a taken and filtered using whattmann filter paper. To the drawer assembly of alpha and beta counting system. filtered water, 10ml of 10% potassium di hydrogen 226 232 40 phosphate, 2ml of CaCl2 and ammonia solution is added and Estimation of Ra, Th and K in the samples is left for a night. Decand the supernatant liquid and were carried out by using high resolution gamma ray dissolve the precipitate in concentrated Hcl. Reduce the spectrometry comprising a high purity NaI volume and add 1ml of concentrated H2SO4 and 1ml of detector.Estimation of natural radioactivity were carried barium carrier. BaSO4 precipitate is taken in a clean and dry out by measuring the following gamma energies namely planchet and it is ready for analysis. Radioactive nuclides 226 Ra directly through the 186.2 KeV and indirectly present in water were estimated using gamma ray 214 232 spectrometer and alpha and beta was determined by the by measuring the Bi (609.3 KeV) and Th is 228 40 respective counting system. estimated through Ac (911.2 KeV) and K through the 1460.8 KeV photopeaks. All the measurements were Vegetable sample: For vegetable about 500grams of carried out for 5000 seconds. banana was collected from the sampling area. It was washed thoroughly with water and cut into pieces and dried in hot air oven at a temperature of 1500c for four hours. The sample is taken in a silica crucible and ashed it in muffle 0 furnace at a temperature of 600 c for 4 hours and the sample is ready for analysis by using respective counting systems. _______________________________________________________________________________________ Volume: 04 Issue: 12 | Dec-2015, Available @ http://www.ijret.org 189 IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 Results and Discussions Sources of heavy minerals in the beach sands of Thengaipattinam coast are ilmenite and monazite present in Table 1: Gross Alpha activity in the samples it. The concentration of heavy minerals in the beach sands No. Sample Gross α activity is due to favourable geological conditions. Natural 1. Soil 27546 Bq/Kg radioactivity content reported from these regions is mainly 2. Water 0.0065 Bq/l due to the monazite bearing black sands. 3. Veg. (Banana) 91.02 Bq/Kg 4 fish 115.72 Bq/Kg REFERENCES [1] United Nations Scientific Committee on the effects of Atomic Radiation.1993., Dose assessment Table 2: Gross Beta activity in the samples methodologies , United Nations, Newyork. [2] Mir Azam Ali, Krishnan s. and No. Sample Gross β activity Banerjee,D.C.,2001.Beach and heavy mineral sand 1. Soil 94718.23 Bq/Kg investigations and deposits in India-An overview, 2. Water 0.032 Bq/l special issue on beach and inland heavy mineral sand 3. Veg. (Banana) 220 Bq/Kg deposits of India. Exploration and Research for 4 fish 302.15 Bq/Kg Atomic minerals, 13, pp.1-21. [3] Aswathanarayana.U, 1964. Origin of the heavy mineral beach sand deposits of the south west coast of India. In: Table 3: Gross Gamma activity in the samples Eds.A.P.Subramanian and S.Balakrishna-Advancing Gross Gamma Activity (Bq/Kg or Bq/l) Frontiers in Geology and Geophysics, Indian Geophysical union, Hyderabad, pp.481-489. No. Sample 228 40 232 Bismuth Actinium Potassium Thorium [4] Fisenne I.M.,Perry P.M.,Docher, K.M and Keller,H.W.,1987.The daily intake of 234, 235, 238U, 1. Soil 2896 77.51 19.71 10387.92 228, 230, 232Th, 226, 228Ra by Newyork city residents. Health Phys.53:pp.357-363. 2. Water 0.314 0.0029 0.031 5.08 [5] UNSCEAR, 2000. United Nations Scientific Committee on the effects of Atomic Radiation Veg. 3. 0.062 81.33 0.271 0.992 (UNSCEAR), Sources Effects and Risks of Ionizing (Banana) Radiation Report to the General Assembly, United 4 fish 0.047 111.78 0.386 1.573 Nations, New York, USA.