ABSTRACT
Radon is an odourless, colourless and tasteless gas and it is the first cause of lung cancer among non- smokers. The assessment of the level of radium in building materials helps in understanding the radiological implications. It has been observed that everyone has some levels of exposure to them. Therefore measurement of radium and radon in the soil samples are important from public health point of view. In the present work, radon exhalation rate and radium from soil samples have been measured through "Sealed Can technique" using LR-115 type II plastic track detector. Twenty two samples were collected from industrial area of Bulandshahr, Hapur and Meerut districts of Uttar Pradesh [India]. The radium concentration ranges from 9.2 to 18.7 Bqkg[-1] with an average value of 14.1 Bqkg[-1]. The area exhalation rate for radon ranges from 394.1 to 798.3 mBqm[-2] h[- 1] with an average value of 600.7 mBqm[-2] h[-1] and mass exhalation rate ranges from 15.1 to 30.7 mBqkg[-1]h[-1] with an average value of 23.1 mBqkg[-1]h[-1]. A strong correlation coefficient has been observed between radium concentration and radon exhalation rate. The values of radium concentration in all the soil samples were found to be lower than the limit 370 Bqkg[-1] as recommended by OECD, 1979. Hence, there is no matter of concern to the population living in this region
ABSTRACT
More than 50% of the total dose received by human beings from all sources of radiation [both from natural and manmade] comes from radon and its progeny which is responsible for lung cancer in many cases. In the present study, the measurements have been carried out by using twin chamber dosimeter cups with LR-115 type-II detectors. The value of track density of detectors gives the concentration of radon, thoron and their progeny in different modes. The average value of radon and thoron concentration was found 59 and 28 Bq/m[3], respectively. The inhalation dose was found to vary from 1.6 to 2.9 mSv/y. The average value of PAEC for radon and thoron was found 6.4 mWL and 0.75 mWL, respectively. Total annual exposure and annual effective dose varies from 0.23 to 0.39 WLM and 0.87 to 1.51 mSv/y respectively. The values of life time fatality risk was found to vary from 0.68 x 10[-4] to 1.18 x 10[-4]. These measurements show that the radon/thoron concentrations and annual effective dose received by the population of the area are well below the action level recommended by the International Commission on Radiological Protection [ICRP]
ABSTRACT
Everyone is exposed to radon because it is present everywhere with varying concentrations. Radon and its progeny are well established as lung carcinogenic. Track etch technique using LR-115 plastic track detectors has been used to measure the effective radium content and radon exhalation rates in soil samples collected from urban area of Etah district of Uttar Pradesh province in Northern India. The values of effective radium content are found to vary from 27.87 to 45.14 Bq.kg-[1] with a mean value of 34.98 Bq.kg-[1]. The mass exhalation rates of radon vary from 2.38 _ 10[-6] to 3.86 _ 10[-6] Bq.kg[-1].d[-1] with a mean value of 2.99 _ 10-6 Bq.kg[-1].d[-1]. The surface exhalation rates of radon have been found to vary from 6.19 _ 10[-5] to 10.03 _ 10[-5] Bq.m [-2].d[-1] with a mean value of 7.77 _ 10[-5] Bq.m [-2].d[-1]. Radon exhalation study is important for understanding the relative contribution of the material to the total radon concentration found inside the dwellings. The values of radium and radon exhalation rates are found to be below the safe limit recommended by OECD, 1979