Consequences of the Chernobyl reactor accident for the Munich area

The radiological effects were detectable since April 30, 1986, measurements revealed a fallout of about 400 kBq/m2 of gamma-ray emitters, consisting a.o. of 70 kBq/m2 of I-131 and 30 kBq/m2 of Cs-134 and Cs-137. The gamma dose rate in open air increased to about 1 μSv/h (i.e. twelve times the natural background). Contamination of grass-lands and green-leaf vegetables in May was measured to be about 20.000 Bq/kg of I-131, and some 1000 Bq/kg of Cs-134 and Cs-137. I-131 nuclides in fresh milk accounted for a contamination of 100-1.000 Bq/l. In meat, some 100 Bq/kg of Cs-134 and Cs-137 were peak values. The reference value set for milk was 500 Bq/l of I-131, and for green-leaf vegetables 250 Bq/kg of I-131. This meant that sales of milk had to be restricted, and the harvest of contaminated vegetables completely dumped. Prognostic dose values calculated for the year 1986 are: Thyroid dose to infants, about 10 mSv (1 rem); effective dose to adults and children induced by all possible sources, about 0.5 mSv (50 mrem), but 1 mSv (100 mrem) as a maximum. Whole-body countings indicated a mean radiation dose to persons living in the Munich area of about 3 mSv (300 mrem) thyroid dose to children from I-131, and about 0.1 mSv (10 mrem) effective dose to children from I-131, and about 0.05 mSv (5 mrem) to children and adults from the incorporation of Cs-134 and Cs-137. There was no accute health hazard to the population, and all values measured were within the intensities and fluctuation margins of the natural radiation exposure. (orig./HP)