Natural Radioactivity Levels in Moradabad District of Western Uttar Pradesh, India

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1 INT J CURR SCI 2016, 19(4): E RESEARCH ARTICLE ISSN Natural Radioactivity Levels in Moradabad District of Western Uttar Pradesh, India Indu Singh and Nikhil Rastogi* Department of Physics, School of Sciences, IFTM University, Moradabad , UP, India *Corresponding author: nr.cetiftm@gmail.com Abstract Measurement of indoor radon and thoron has been carried out in the residential houses of district Moradabad Uttar Pradesh, India using solid state nuclear track detectors. Radon is an invisible radioactive gas that occurs naturally in the indoor atmosphere. Radon and thoron are the most important contribution of human exposure from natural sources. Radon exists in soil gas, building materials, Indoor atmosphere etc. Lung cancer risk depends upon the concentration of radon and thoron and their decay products in environment above recommended levels. The work presented here emphasizes the measurement of indoor radon and thoron concentration in 60 dosimeters using solid state nuclear track detector in different types of dwellings of Moradabad district, U P. The measurements were made in residential houses at a height of 2 meters from ground levels using a twin chamber radon dosimeter. In the present study, the value of concentration of radon range from 10.5 Bq/m 3 to 29.5 Bq/m 3 with an average19.8 Bq/m 3 and thoron concentration varies from5.6 Bq/m 3 to 24 Bq/m 3 with an average of 14.9 Bq/m 3 respectively. The result obtained with twin cup radon/thoron dosimeter show that the concentration of indoor radon and thoron were found within recommended levels. All the values in the above study have been found under the safe limit laid down by International commission on Radiological protection (ICRP) and United Nations Scientific Committee on the effect of Atomic Radiation (UNSCEAR). Keywords: Radon/Thoron; Residential houses; Dosimeter; Solid State Nuclear Track Detector Received: 15 th September 2016; Revised: 24 th September; Accepted: 02 nd October; IJCS New Liberty Group 2016 Introduction Studies of natural radioactivity and natural environmental radiation are of great importance as they are in interest of Health Physics, Radiation Physics and all allied branches of natural Sciences. The measurement of the concentration of radon and thoron in indoor atmosphere has been the interest of much research for Scientists all over the world. According to Ramachandran et al. (2003), in our daily life, we come across both natural as well as man-made sources of radiation. The natural sources are cosmic rays and the natural radioactivity present in the soil and rocks respectively. The behaviours of the radioactive gases have received considerable attention over the past few decades due to the radiological risks to humans in indoor atmosphere. High radon levels were measured in dwellings in a number of countries including United States, Sweden and United Kingdom UNSCEAR (2000) and there is a concern that levels of radon may contribute to an increased risk of lung cancer. These high indoor radon levels can exceed international guidelines and

2 are associated with a number of factors including soil porosity, uranium content of the soil, building materials mode of construction, ventilation and metrological parameters as suggested by Bajwa et al. (2008). The variability of these factors accounts for the large range of the radon levels measured in dwellings. Recent epidemiological evidence suggests, report WHO (2007, 2008) that inhalation of radon decay products in domestic environments could be a cause of lung cancer. The important factors that have got influence up on the indoor radon/thoron concentration are: (i) Properties of the building construction material and the ground. Here the radon exhalation rate from the building concentration materials or the ground is performed in order to estimate the indoor radon and thoron concentration levels of Moradabad district of western Uttar Pradesh. Measurements were made residential houses in bedroom as well as drawing rooms (Choubey et al., 2003). The residential houses in plane area are selected for installation of dosimeters which are mostly poor ventilated having small one window or without window. Measurement techniques Concentration of radon and thoron in environment were measured in 60 houses of the Moradabad district of Western Uttar Pradesh using alpha sensitive LR-115 type II plastic track detectors, fig. 1. Fig. 1. Twin Cup Radon - Thoron Dosimeter dependent on the uranium/thorium content, density and the porosity of the material. (ii) Indoor radon/thoron concentration are also influenced by the ventilation rate and metrological parameter (Sharma et al., 2014). The radon and thoron levels have been measured using solid state nuclear track detectors in various types of houses at 10 different locations around Bangalore city, India. 220 Rn levels were observed higher than the global average of 10 Bq/m 3. Ramola et al. (2000, 2005) surveyed in Dehradun and nearby towns of U.P. and suggest a little higher concentration of radon than the normal one; hence radon concentration survey was required for different regions of the state. So, Moradabad district of western Uttar Pradesh are chosen as study area. The aim of proposed investigation is to carry out the systematic study of radon and thoron concentration in indoor atmosphere in dwelling of Moradabad district. The study was It is a 12 micrometer thick film red dyed cellulose nitrate emulsion coated on inert polyester base of 100 micrometers thickness and has maximum sensitivity for alpha particles. Eappan et al. (2004), Zhuo et al. (2000, 2001), Duggal, et al. (2013) took small pieces of detector film of 2.5 cm x 2.5 cm. (will be fixed in a twin cup radon dosimeter having three different mode holders namely bare mode, filter mode and membrane mode. According to Eappan et al. (2001), Tokonami et al. (2003), Khan et al. (2014) bare mode detector registers track due to radon gas and their progeny concentrations, while the filter

3 mode detector records tracks due to the radon and gas, membrane made records tracks only by radon gas. The dosimeters fitted with LR-115 plastic track detector are suspended inside the selected houses in field area at a height of about two meters from the area are poorly ventilated. Buildings are constructed of concrete, cement, bricks and blocks. Some houses, having glass doors and glass windows are also included in study. Fig. 2. Map of Moradabad District ground floor. When alpha particles strike on LR-115 film, it creates narrow trails called tracks. The detectors were exposed for about three months and after retrieval, were etched and scanned in the laboratory for the track density using spark counter, Milic et al. (2013), Singh et al. (2015). The measured track densities for indoor radon and progeny were then converted into working levels (WL) and activity concentrations (Bq/m 3 ) using the following calibration factors used by Ramola et al. (1996, 1997, 2005). 125 tracks cm 2.d 1 =1 WL 3.12x10 2 tracks cm 2 d 1 = 1 Bq/m 3 Area for study Moradabad districts are situated in Western Uttar Pradesh, a state of India. According to Mishra, (2014) Moradabad district forms a part of genetic alluvial plain and lies between and 29 0 North latitudes and and 79 0 East longitude covering an area of about sq. km (Fig. 2). The area of the Moradabad can be divided into two broad geological unities namely Younger Alluvium and Older Alluvium. Moradabad district is having main two rivers Ram Ganga and Gagan Rivers respectively. The ground of the Moradabad is almost plane but some places are as ups and downs. The River water contains soil, silt and sand in varying proportion. The soil of the Moradabad is mainly three type-domat, matiyaan and bhud. The houses in study Results and Discussion The work presented here emphasizes the long term measurements of radon and thoron concentrations in 60 dwellings using solid state nuclear track detectors (Table 1). The residential houses were chosen for installing dosimeters; new as well as old one, Kumar et al. (2014). The dwellings in the study area are mainly made of bricks using cement and concrete. The selection of dwellings for installing dosimeters was done taking into account the degree of ventilation, type of floors, number of windows and doors as they all responsible for variation in indoor radon/thoron concentration. All the measurements were taken around noon in different seasons. However, the recorded values of radon, thoron progeny and resulting does are well below internationally recommended levels. This clearly indicates, Rawat et al. (2011), that the houses in area in Central Uttar Pradesh are quite safe from the radiation protection point of view. In present

4 study, it is observed that the minimum indoor radon concentration 10.5 Bq/m 3 was recorded in Jigar Colony in summer (reading taken around noon) while the highest concentration 29.5 Bq/m 3 is recorded in Chow ki Basti in winter season. The overall average value of indoor radon concentration was found 19.8 Bq/m 3 for the complete year. The minimum indoor colony in summer (reading taken around noon), While the highest thoron concentration 24 Bq/m 3 is recorded in Reti Muhhala in winter season (reading taken around noon). The overall average value of the indoor thoron concentration was found 14.9 Bq/m 3 for the complete year. The concentration was found least in summer while highest observed in winter. thoron concentration 5.6 Bq/m 3 was recorded in Jigar Table 1. Variation of Indoor Radon and Thoron concentration in different seasons Sample Locations in Moradabad District Environmental Indoor Radon Concentration (Bq /m 3 ) Environmental Indoor Thoron Concentration (Bq /m 3 ) Autumn Summer Rainy Winter Autumn Summer Rainy Winter Lodhipur Pakwara Mangupura RadhaKrishan Mandir Manjholi Mansrover Colony Budhi Vihar Prem Nagar Chow ki basti Gulab bari Petal Basti Sita puri Mandichawk Jigar colony Harthala colony Chandan nagar Ram Ganga Vihar Town Hall Gaytri Nagar Rati muhala Hanuman Nagar Vikas Nagar Minimum Concentration Maximum Concentration Average Concentration

5 Thoron Concentration (Bq/m3) Lodhipur Pakwara Mangupura RadhaKrish Manjholi Mansrover Budhi Vihar Prem Nagar Chow ki Gulab bari Petal Basti Sita puri Mandichawk Jigar colony Harthala Chandan Ram Ganga Town Hall Gaytri Nagar Rati muhala Hanuman Vikas Nagar Radon Concentration (Bq/M 3 ) Lodhipur Pakwara Mangupura RadhaKrishan Manjholi Mansrover Budhi Vihar Prem Nagar Chow ki basti Gulab bari Petal Basti Sita puri Mandichawk Jigar colony Harthala colony Chandan nagar Ram Ganga Vihar Town Hall Gaytri Nagar Rati muhala Hanuman Nagar Vikas Nagar Indu Singh and Nikhil Rastogi, 2016 Fig. 3. Graphical Variation of Radon Concentration Seasonal Variation of Radon Concentration in Moradabad Autumn Summer Rainy Winter Sample locations in Moradabad district Fig.4. Graphical Variation of Thoron Concentration SeasonalVariationofThoronConcentration in Moradabad Autumn Summer Rainy Winter Sample locations in Moradabad district This is because, in summer season, the houses remain open for long time which contributes in increasing air exchange rate while in winter; the rooms are remaining closed for long hours decreasing air exchange. This is the possible cause for radon/thoron variation, shown in figs. 3 and 4. The results of systematic study are obtained by considering the room as a space in which the radon and thoron levels are directly related to the dynamic and static parameters. Conclusion Based on the results obtained, from the houses of Moradabad district of Uttar Pradesh for all four seasons, it is concluded that the measurement values

6 are comparable to the recorded values of radon and thoron, BEIR (2006) and the measured results of the tables are well below internationally recommended levels Therefore the results clearly indicate that the houses in areas of Moradabad district of Western Uttar Pradesh are quit safe for the radiation protection point of view. The building materials can slightly influence the indoor radon concentrations. Brick and concrete houses show increased radon levels, while wood and adobe houses present low radon concentrations. Moreover, the floors have also an impact on radon concentrations as well as the existence of concrete floor capping, Armencea (Mutoiu) et al., Acknowledgement Authors express their sincere thanks to the Vice Chancellor of IFTM University, Moradabad for providing the necessary facilities and his constant encouragement to carry out the research work. The authors wish to acknowledge the residents of different places in the district Moradabad, where the readings were taken and also the research group of Physics Lab, IFTM University for their help during the installation of apparatus at different places. References Armencea (Mutoiu) ES, Armencea A, Burghele B, Cucos (Dinu) A, Malos C, Dicu T (2013). Indoor radon measurements in Bacau County. Rom J Phys 58: S Bajwa BS, Singh H, Singh S, Walia V (2008). A combination study of indoor radon and gamma radiation levels in Tusham ring complex, Radiation Measurements 43: S475- S478. BEIR VII Phase-II (2006). Health Risks from Exposure to Low Levels of Ionizing Radiation, The National Academies Press, Washington DC, USA, pp Choubey VM, Bartarya SK, Ramola RC (2003). Radon in ground water of eastern Doon valley, Outer Himalaya. Radiat. Meas 36: Duggal V, Rani A, Mehra R (2013). A study of seasonal variations of radon levels in different types of dwellings in Sri Ganga nagar district, Rajasthan. J Rad Res App Sci 7: Eappen KP, Ramachandran TV, Shaikh AN, Mayya YS (2001). Calibration factor for SSNTD Based radon /thoron dosimeter. J Radit Prot Envir 24: Eappen KP, Mayya YS (2004). Calibration factor for LR-115 type-ii based radon thoron discriminating dosimeter. Radia Mea 38: 5. Khan MSA, Tariq M, Rawat RBS (2014). Environmental Monitoring of radon-thoron Levels and Their Seasonal Variation in Some Selected Dwellings in and Around Rampur City Using Solid State Nuclear Track Detector (SSNTD). IJSR 4: Kumar, A, Saxena A, Rawat RBS, Sharma D (2014). Natural Radioactivity levels in some village in Shahjahanpur, Uttar Pradesh, India. Int J Engg Sci Inv 32: 1-3. Mishra P, Rawat RBS, Sharma VK, Saxena A (2014). Concentration of radon and its Progeny levels in air in the Dwelling of Moradabad of western UP, India. Int J Sci Eng Res 5:

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