Contribution from natural and man-made background radiations to Indian population

Living organisms are exposed to ionizing radiation existed naturally. Sources of ionizing radiation are cosmic ray, which comes from outer space, terrestrial radionuclides which occurs in the earth's crust, in building materials and in air, water and food and in human body itself. The annual effective dose at sea level from cosmic rays is 240 μSv. It can also vary as a result of human activities and practices. Component of the sources of exposures to Indian population has been assessed based on the data generated. Total contribution to the natural sources to the Indian population works out to be 2.3 mSv/y as against the global value of 2.4 mSv/y. Estimated contribution to the background radiation from actual practices such as mining of heavy metals (U and Th), coal fired power plants, mining of phosphate rocks and its use as fertilizers, production of natural gas, production of gas mantles and luminescent dial and air travel works out be 1.24 x 10-3mSv/y. Nuclear weapon tests contributes about 0.008 mSv/y and the exposure due to nuclear power production contributes about 5.0 x 10-5 mSv/y to the background radiation. Brief review and comparison of the dose rates arising from natural and man-made sources to the Indian population is given. (author)