Human body radon exposure

The occupational, accidental, and wartime experiences have provided the basis for the estimation of risk to humans following radiation exposure. However, cosmic, cosmo-genic, inhaled, and in-body radiation deliver total body effective doses of 3 becquerel per year total effective dose. The average radon concentration indoors is 40 becquerel... 

The estimation of dose rates from the internal exposure to the series and Th series is more difficult. UNSCEAR (2000a) surveyed their contents in the human body and their dietary intake, and estimated aimual effective doses from ingestion of the radionuclides from uranium- and thorium- series are shown in Table 55.15. The exposure due to these radionuclides contained in the body (120 pSv a ) is almost the same as that from food intake, 110 pSv a . In the series of and Th (disregarding radon, thoron, and their shortlived daughters) Pb/ Po contributes most to the exposure (about 75%). 

When radioactive substances pass into the body by inhalation of radioactive vapors, gases (e.g., radon) or dusts, or by ingestion, such substances may accumulate and deposit in the bone. They incorporate in the bone matter the ionizing radiations damage cells and cause cancer. Cancer in lungs, bones, and lymphatic systems are known to occur in humans as a result of radiation exposures. 

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