Radioactivity levels in some sediment samples from Red Sea and Baltic Sea.

Levels of ²²⁶,²²⁸Ra, ²³²Th, ²¹⁰Pb, ²¹⁰Po and ⁴⁰K in sediments from four monitoring areas, El Hamraween and Ras El Behar (Red Sea, Egypt) and LL3A and JML (Baltic Sea, Finland), have been investigated using alpha and gamma spectrometry. The average activity concentrations were 238±4 Bq kg⁻¹ (²²⁶Ra), 215±11 Bq kg⁻¹ (²¹⁰Pb) and 311±18 Bq kg⁻¹ (²¹⁰Po) for El Hamraween area. In Ras El Behar area, the corresponding values were 16±0.4, 18±1 and 20±5 Bq kg⁻¹, respectively. The activity concentrations for ²²⁶Ra, ²¹⁰Pb and ²¹⁰Po (uranium series) in El Hamraween bottom sediment are much high compared with those in Ras El Behar area, which indicates the enhanced levels due to the activities of phosphate mining and shipment operations in El Hamraween area. Excluding the influence of phosphate mining activities, it can be concluded that the levels of radioactivity in Baltic Sea sediments are higher than those in Red Sea sediments.