Radioactivity measurements of chemical and organic fertilizers applied to farms in the Kurdistan Region, Iraq

The use of chemical and organic fertilizers in the farms of the Kurdistan region has increased because of land reclamation and agricultural activities. The ores used in some chemical fertilizers contain various amounts of radioisotopes such as ²³⁸U, ²³²Th, ⁴⁰K and ¹³⁷Cs. For this reason, chemical fertilizers are considered one of many sources of radionuclides and radioactivity in the environment. In this work, the specific activities of ²³⁸U, ²³²Th, ⁴⁰K and ¹³⁷Cs in samples of twenty common chemical fertilizers and of five organic fertilizers were estimated by using a gamma ray spectrometer based on the NaI(Tl) detector<i>.</i> The total average activity concentrations of ²³⁸U, ²³²Th, ⁴⁰K and ¹³⁷Cs were 8.81, 8.31, 2360.36 and 0.07 Bq kg^-1, respectively. In general, chemical fertilizers revealed higher radioactivity than organic fertilizers, and the agricultural application of these fertilizers may cause health risks unless their usage has been controlled scientifically.