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Background radiation, people and the environment
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| T.V. Ramachandran |
| , tvrradfon2@gmail.com |
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Abstract: (17539 Views) |
| All living organisms are exposed to ionizing
radiation comprising cosmic rays coming from outer
space, terrestrial nuclides occurring in the earth’s
crust, building materials, air, water and foods and in
the human body itself. The exposures are constant
and uniform for all individuals everywhere including
the dose from ingestion of 40K in food. Cosmic rays
are, more intense at higher altitudes, and the levels
of uranium and thorium in soils are elevated in
localized areas. Exposures also vary as a result of
human activities and practices. In particular, building
materials of houses and the design and ventilation
systems strongly influences the indoor levels of the
radioactive gas radon and its decay products, which
contributes the doses through inhalation. Component
of the sources of exposures to Indian population has
been assessed based on the data generated. Total
contribution from the natural sources to the Indian
population works out to 2.3 mSv/y as against the
global value of 2.4 mSv/y. Estimated modified source
including mining of heavy metals, coal fired power
plants, mining of phosphate rocks and its use as fertilizers,
production of natural gas, gas mantles and
luminescent dial and air travel contribution to the
background radiation to the Indian population works
out to be 1.2 x 10-3 mSv/y atmospheric weapon tests
contributes about 0.045 mSv/y, medical exposure
contributes about 0.048 mSv/y and 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. Iran. J. Radiat. Res., 2011 9(2): 63-76 |
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| Keywords: Background radiation, radon, cosmic rays, external exposure, internal exposure. |
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Full-Text [PDF 299 kb]
(8893 Downloads)
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Type of Study: Short Report |
Subject:
Radiation Biology
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