Abstract
Concentrations of uranium-238 and thorium-232 in soil, water, grass, moss and oil-palm fruit samples collected from an area of high background radiation were determined using neutron activation analysis (NAA). U-238 concentration in soil ranged from 4.9 mg kg (super -1) (58.8 Bq kg (super -1) ) to 40.4 mg kg (super -1) (484.8 Bq kg (super -1) ), Th-232 concentration ranged from 14.9 mg kg (super -1) (59.6 Bq kg (super -1) ) to 301.0 mg kg (super -1) (1204 Bq kg (super -1) ). The concentration of U-238 in grass samples ranged from below the detection limit to 0.076 mg kg (super -1) (912 mBq kg (super -1) ), and Th-232 ranged from 0.008 mg kg (super -1) (32 mBq kg (super -1) ) to 0.343 mg kg (super -1) (1.372 Bq kg (super -1) ). U-238 content in water samples ranged from 0.33 mg kg (super -1) (4.0 Bq L (super -1) ) to 1.40 mg kg (super -1) (16.8 Bq L (super -1) ), and Th-232 ranged from 0.19 mg kg (super -1) (0.76 Bq L (super -1) ) to 0.66 mg kg (super -1) (2.64 Bq L (super -1) ). It can be said that the concentrations of environmental U-238 and Th-232 in grass and water samples in the study area are insignificant. Mosses were found to be possible bio-radiological indicators due to their high absorption of the heavy radioelements from the environment. Abstract Copyright (2005) Elsevier, B.V.