Distribution of natural radionuclide concentrations in sediment samples in Didim and Izmir Bay (Aegean Sea-Turkey)

Natural and artificial radionuclide pollutants of the marine environment have been recognized as a serious environmental concern. The natural radioactivity activity concentrations of 226Ra, 238U, 232Th and 40K were measured by gamma spectrometry in sediment samples collected from two different areas in Aegean Sea Turkish Coast. There is no information about radioactivity level in the study areas sediments so far. The results showed that the concentrations of activity in the sediment samples are 9 ± 0.6 Bq kg−1–12 ± 0.7 Bq kg−1, 7 ± 0.4 Bq kg−1–16 ± 1.0 Bq kg−1, 6 ± 0.3 Bq kg−1–16 ± 1.0 Bq kg−1 and 250 ± 13 Bq kg−1–665 ± 33 Bq kg−1 for 226Ra, 238U, 232Th and 40K, respectively. In general, the distribution of activity concentrations along the coast of the Aegean Sea area were in the same order as international levels.

► Levels of 226Ra, 238U, 232Th and 40K in marine sediments at the Aegean Sea.
► The highest activity concentrations of 232Th and 238U were observed in Izmir Bay.
► The highest activity concentrations of 40K in Didim.
► There is not much difference between the concentrations of radionuclides in sediment.