RADIONUCLIDES 134Cs AND 137Cs IN EEL (Anguilla anguilla L.) IN FINNISH FRESHWATERS AFTER THE ACCIDENT AT CHERNOBYL NUCLEAR POWER STATION IN 1986

Abstract

The concentrations of ¹³⁴Cs and ¹³⁷Cs in eel after the Chernobyl accident in 1986 were analysed from nine lakes and two rivers during 1986-1992 in different parts of the country. The ratio of ¹³⁴Cs to ¹³⁷Cs was in 1986 about 0.5 but decreased gradually to 0.09 in 1992. In the same area the concentrations of ¹³⁷Cs increased slower in the eel than in the other fish species. The highest concentrations of ¹³⁷Cs (3580-3760 Bq/kg fresh weight) in eel were detected in small oligotrophic lakes in the area of the highest deposition four to five years after the accident.