Integrated natural radiation exposure studies in stable Yugoslav rural communities

The results of field investigations of natural radiation exposures of the general populations in twostable rural communities in Yugoslavia are presented. The principal emphasis was on exposures tocontemporary indoor radon but measurements of external penetrating radiation absorbed dose rates inair were carried out in the majority of cases. In addition in a limited number of dwellings,measurements of thoron gas concentrations were made. By means of making a series of sequentialthree month radon measurements, both seasonal variations and annual average radon levels in thedwellings were determined. Using passive alpha track detectors, individual radon and thoron indoorconcentrations as high as 9591 Bq/m3 and 709 Bq/m3 respectively were detected while absorbed doserates in air in the dwellings as high as 430 nGy/hr were recorded.On the basis of these different types of measurements, assessments could be made of the integratednatural radiation exposures being received by the populations. In addition to contemporary radonmeasurements, retrospective radon exposure assessments in most of the dwellings were made on thebasis of measurements of 210 Po concentrations in both surface (glass) traps and in volume (porousmaterials) traps.A description is given of the sampling strategies and protocols used in this field work. It is shown thatat least one stable rural community receiving high natural radiation exposures, has been clearlyidentified and plans for future health investigations of the population there are outlined.