PERCEPTION OF NATURAL, MEDICAL, AND 'ARTIFICIAL' RADIATION EXPOSURES

摘要

For somebody who has been involved for 35 years in various continents and various responsibilities in radiation protection, it remains difficult to understand why such incredibly different weighting factors are attached by the media, and consequently by many politicians and non-technical organizations as well as by the general public, to the risks associated with the three main sources of population exposures, namely: 1. 'natural' radiation, amounting to about 75% of the total collective radiation dose during the past 50 years [1-3], with very large local fluctuations with or without modifications by human activities (e.g. up to 1:10~6 in ambient radon concentrations, apparently without detrimental health effects for anybody but very heavy smokers in very high radon environments); 2. diagnostic or therapeutic medical exposures amounting to about 24% of the collective radiation dose, which could easily be substantially reduced in many cases by simple means, without any loss of benefit; and 3. the very small additional 'artificial' component (mostly due to early nuclear weapons tests, the nuclear fuel cycle, the Chernobyl accident and industrial uses of radiation) amounting to a total of less than 1 % of the above.