Strontium-90 concentrations in human teeth in south Ukraine, 5 years after the Chernobyl accident.

Approximately 1000 human teeth, collected in South Ukraine, in 1990-1991, were measured for 90Sr concentration. The teeth were grouped into 18 samples according to the age and sex of the donors. Measured levels of 90Sr concentrations were lower by a factor of 10 than measurements taken in the mid-1960s and mid-1970s. An interesting feature of the data is a 3-fold enhancement of contamination levels in the 25-45 year-old age group of the male population. A possible explanation for this anomaly is that this age group contains a significant number of men who were mobilized immediately after the Chernobyl accident for clean-up operations within the 30-km zone around the damaged nuclear power plant.