Prevention of internal exposure to Cesium-137 ((137)Cs) radiation in inhabitants of an area contaminated by the chernobyl accident.

On April 26th 1986, an accidental explosion occurred at Chernobyl nuclear power station #4, located in the Ukraine, in the former Soviet Union. From May 1991, in order to prevent internal exposure to cesium-137 ((137)Cs) in the inhabitants of the Chechersk district of the Gomel region in the Republic of Belarus, which was an area highly contaminated by the Chernobyl accident, the author continuously measured internal(137)Cs accumulations within inhabitants of the district with a whole-body counter, and the levels of(137)Cs in milk, beef, pork, mushrooms, potatoes and flour with a GM-semiconductor detector.Then the author analyzed the relationships between the inhabitants' daily habits and their measured cesium levels. The author measured(137)Cs accumulation within 528 inhabitants and in agricultural produce in the Chechersk disrict.There was no correlation between the internal(137)Cs levels within inhabitants and the surface contamination by(137)Cs within the residential area. However, a comparison of internal exposure levels by age and sex revealed a significant variation between adult males and both male and female children, and between adult males and females (p < 0.001).Food supplied in school was the cause of lower levels in children because it was strictly controlled by the local health authority. The difference between adult males and adult females was thought to be due to the difference in the length of working time in the fields, or in the amount of food from pastures, lakes and forests.Some of the measurement values of agricultural produce with the GM-semiconduc-tor detector exceeded the provisional standards of the Ministry of Health of the Republic of Belarus, where milk, beef, pork and mushrooms had been measured while potatoes and flour had not.Results for milk (r = 0.829), beef (r = 0.916), pork (R= 0.896) and mushrooms (r = 0.670) all showed a strong correlation with the concentration of(137)Cs on the surface for fields and pastures, while those for potatoes and flour showed no correlation.According to this survey, the internal levels of(137)Cs of inhabitants living within the contaminated areas were not related to the concentration of(137)Cs in the residential areas, but to the foodstuffs they consumed. Thehefore, by avoiding contaminated foodstuffs, the inhabitants could reduce internal exposure and their risk.