Distribution pattern of Sr-90 and Cs-137 in the Nile delta and the adjacent regions after Chernobyl accident

Strontium and cesium contents in surface soil samples across the Nile Delta and the north coast of Egypt after the Chernobyl accident have been invest igated. The concentration of Cs-137 and Sr-90 was determined using a high r esolution gamma spectrometer based on hyperpure germanium detector (HPGe) a nd a liquid scintillation counter (LSC) respectively. 90Sr was determined t hrough its decay product Y-90 using Cerenkov counting. The determination of 90Sr was based on tributylphosphate (TBP) extraction of yttrium from nitri c acid extract of ashed samples. The radioactivity of soils ranged between 18.5 and 2175 Bq/m(2) with a mean of 652 Bq/m(2) and 234 and 3129 Bq/m(2) w ith a mean of 760 Bq/m(2) for Cs-137 and 90Sr respectively. An estimated ab sorbed dose equivalent due to the measured deposit of Cs-137 was found to b e 0.062 mu rem/h. (C) 1999 Elsevier Science Ltd. All rights reserved.