RADIOACTIVE DISEQUILIBRIUM AND DYNAMIC OF NATURAL RADIONUCLIDES IN SOILS IN THE STATE OF PERNAMBUCO-BRAZIL

Environmental radioactivity studies have been allowed establishing radiometric patterns in several area of the earth's crust. The work was conducted through radiometric analyses of regions with high levels of radionuclides and others with no history of anomalies. The research allowed establishing the radiometric profile of soils in the state of Pernambuco, Brazil, using a gamma spectrometry system. The specific activities ranged from 16.5 to 287.5 Bq kg(-1) for U-238, 2.0 to 191.7 Bq kg(-1) for Ra-226, 1.3 to 281.4 Bq kg(-1) for Th-232 and from 5.0 to 2600.9 Bq kg(-1) for K-40. The results showed areas with low levels of ionizing radiation. However, for K-40 some points presented high values, although non-representative of the number of samples investigated. The Ra-226/U-238 and Th-232/U-238 ratios allowed to determine the radioactive imbalance condition and to obtain information about aspects of soil availability providing an assessment of the dynamics of these radionuclides.