Abstract
Translocations are an indicator of the effects of all kinds of clastogens such as chemicals and metabolic factors as well as radiation. We reported the frequencies of chromosome translocations in the peripheral lymphocytes of people in the normal living circumstance. Average genomic frequencies of translocations in 1,000 cells in 20 residents (61.2 year-old on average) in a large city and in 16 residents (64.4 year-old on average) in a remote village and in 8 children (12.3 year-old on average) in the remote village were 9.6, 8.4, and 3.2, respectively. Their standard deviations were 5.0, 3.1 and 2.0. As it is possible to calculate the dose with the frequency of chromosome aberrations, frequencies of translocations were converted to radiation dose according to the dose response formula of chromosome aberrations, assuming that all the translocations had been induced by radiation. Standard deviations of the calculated doses for non-smokers in a large city, non-smokers in a remote village and children in a remote village were 200 mSv, 124 mSv and 80 mSv, respectively in chronic exposures, and 153 mSv, 104 mSv and 72 mSv, respectively in acute exposures. Statistically it is not possible to distinguish the cohort if the difference is within the standard deviation of the control. Therefore, our findings suggest that it may not be possible to detect any effects of radiation to be caused in the human body at least up to124 mSv in adult and up to 80 mSv in child in chronic exposures, and up to 104 mSv in adult and up to 72 mSv in child in acute exposures.
