Abstract: Twenty-five surface (0-20 cm) soil samples were collected from
different locations in Egypt representing non-polluted,moderately and highly
polluted soils. The aim of this study was to evaluate total Co content in
alluvial soils of Delta in Egypt using the delayed Neturen activation analysis
technique (DNAA). The two prominent gamma ray lines at 1173.2 and 1332.5 keV
was efficiently used for ^60Co determination. Co content in non-polluted soil
samples ranged between 13.12 to 23.20 ppm Co with an average of
18.16±4.38 ppm. Cobalt content in moderately polluted soils ranged
between 26.5 to 30.00 ppm with an average of 28.3±1.3 ppm. The highest
Co levels (ranged from 36 to 64.69 ppm with an average of 51.9±9.5);
were observed in soil samples collected from, either highly polluted
agricultural soils due to prolonged irrigation with industrial wastewater or
surface soil samples from industrial sites.