Determination of radioactivity levels and hazards of soil and sediment samples in Firtma Valley (Rize, Turkey)

The natural radioactivity levels in soil and sediment samples of Firtina Valley have been determined. To our knowledge, there seems to be no information about radioactivity level in the Firtma Valley soils and sediments so far. For this reason, soil and sediment samples were collected along the Firtma Valley and analysis on the collected samples were carried out to determine super(238)U, super(232)Th, super(40)K and super(137)Cs radioisotopes using high purity germanium detector. The activity concentrations obtained for super(226)Ra, super(214)Pb, super(214)Bi, super(228)Ac, super(208)Tl, super(40)K and super(137)Cs are given in the unit of Bq/kg. The results have been compared with other radioactivity measurements in different country's soils and sediments. The radium equivalent activity (Ra sub(eq)), the absorbed dose rate (D), the external hazard index (H sub(ex)), the annual gonadal dose equivalent (AGDE) and the annual effective dose equivalent (AEDE) were also calculated and compared with the international recommended values.