External and internal irradiation of a Rural Bryansk (Russia) population from 1990 to 2000, following high deposition of radioactive caesium from the chernobyl accident |
| |
Authors: | C Thornberg R Vesanen E Wallström I Zvonova T Jesko M Balonov S Mattsson |
| |
Institution: | 1. Department of Radiation Physics, Lund University, Malm? University Hospital, 205 02, Malm?, Sweden 2. Department of Radiation Physics, G?teborg University, Sahlgrenska University Hospital, G?teborg, Sweden 3. Department of Radiology, N?L, Trollh?ttan, Sweden 4. Institute of Radiation Hygiene, St Petersburg, Russia
|
| |
Abstract: | In 1990, a joint Nordic-Russian project was initiated in order to make independent estimations of the effective dose to selected
groups of inhabitants in a highly contaminated area around the city of Novozybkov in the western Bryansk region of Russia.
The inhabitants were living in six villages with initial contamination levels of 137Cs between 0.9 and 2.7 MBq m−2. Some villages had been decontaminated, others not. Both school children and adults participated in the study. The external
irradiation of 100–130 inhabitants was determined during 1 month in September-October each year from 1990 to 2000 (except
1999), using individual thermoluminescent dosemeters. The body burden of 137,134Cs was determined by in vivo measurements in about 500 inhabitants annually from 1991 to 2000, and for a subgroup also with
analysis of the 137Cs concentration in urine. The mean effective dose (E) from external and internal irradiation due to 137,134Cs deposition varied between 2.5 and 1.2 mSv per year between 1990 and 2000. The total mean E decreased, on average, by 9% per year, while the mean external dose decreased by 16% per year. The dose rate from internal
radiation decreased more slowly than the dose rate from external radiation, and also showed an irregular time variation. The
contribution from the internal dose to the total E was 30–50%, depending on the village. Predictions for the long-term changes in the effective dose to people living in the
areas are presented. The cumulated E for the 70 years following the accident was estimated to be about 90 mSv with the assumption that both internal and external
dose decrease by 2% per year after year 2000. The highest E during a life-time received by single individuals living in the area may amount to around 500 mSv considering the individual
variations in E. |
| |
Keywords: | |
本文献已被 PubMed SpringerLink 等数据库收录! |
|