Man

In order to monitor changes in radioactivity levels in the Finnish population, whole-body counter measurements were made on three different control groups in 1984-1985. The groups were from the Helsinki area and from the areas around the Loviisa and Olkiluoto nuclear power stations. The Helsinki group was measured with a type, four-crystal whole-body counter in an iron room. The Loviisa and Olkiluoto groups were measured with a mobile, shadow-shield whole-body counter. Only 40K and small amounts of 137Cs activities were detected. The mean value of the 137Cs/K ratio of the Helsinki control group in December 1984 was 0.72 Bq/g of potassium and in December 1985 0.80 Bq/g of potassium. The corresponding values for the Loviisa and Olkiluoto groups were 0.53 Bq/g, 0.56 Bq/g, 0.66 Bq/g and 0.44 Bq/g of potassium, respectively