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Technetium-99 was determined in samples from the 30-km zone around the Chernobyl reactor. Concentrations of 99Tc in soil samples taken from three forest sites ranged from 1.1 to 14.1 Bq kg-1 dry weight for the organic soil layers, and from 0.13 to 0.83 Bq kg-1 dry weight for the mineral soil layers. In particular, for the organic layers, the measured 99Tc concentrations were one or two orders of magnitude higher than those due to global fallout 99Tc. The 99Tc depositions (Bq m-2), based on the sum of the depositions measured in organic and mineral layers, ranged from 130 Bq m-2 within the 10-km zone to about 20 Bq m-2 close to the border of the 30-km zone. Taking the corresponding measured 137Cs depositions into account, it was found that the activity ratio of 99Tc/137Cs ranged from 6 x 10(-5) to 1.2 x 10(-4). It was estimated that about 970 GBq of 99Tc had been released by the Chernobyl accident. This figure corresponded to 2%-3% of the total 99Tc inventory in the core.

Total diet samples were collected to estimate dietary intakes of several radionuclides for Ukrainian males by duplicate portion studies. The samples were collected in the Kiev, Rovno and Volynsky regions in autumn of 1994. Some foodstuffs, including milk and potato, were also collected in the same regions. Daily intakes of 232Th and 238U were estimated to be 2.0 mBq and 7.5 mBq per person, respectively. The estimated daily intake of 40K, 85 Bq per person, was equivalent to that of Reference Man (the intake of a West European and a North American). Daily intakes of 137Cs were found to be quite different between some regions. Daily intakes were 1.8 Bq per person in the Kiev region and 12 Bq per person in the Rovno and Volynsky regions. Daily intake of 134Cs was below 1 Bq per person.