Determination of Ra-226, Th-232, K-40 and Cs-137 activities in soils and beach sands and related external gamma doses in Arikli mineralization area (Ayvacik/Turkey)

Uranium mineralization areas may jeopardize public health and surrounding natural life. In the current study for radioactivity and geochemical analyses, 43 soil, 5 rock and 10 beach sand samples were collected in and around Arikli (Ayvacik, Turkey) uranium mineralization area. Radioactivity levels in the soils (up to Ra-226: 629, Th-232: 240, K-40: 3669 Bq/kg) were found higher than the that of beach sands. Besides, radioactivity of the beach sand samples is found at normal levels (avg: Ra-226: 31, Th-232: 31, K-40: 542 Bq/kg) when compared to worldwide average soil. Dose values indicate that the region have ∼three times higher average gamma radioactivity than the corresponding world average although measured gamma doses ranged up to 687 nGy/h. The high measured values are related to uranium mineralization, alteration zones, faults and Arikli tuff. (authors)