Radioactivity in chemical fertilizers used in Bangladesh

The radioactivity concentrations of 226Ra, 228Th and 40K in different chemical fertilizers, triple superphosphate (TSP), single superphosphate (SSP), diammonium phosphate (DAP), phosphogypsum, muriate of potash (MOP), urea, zinc sulfate and zinc oxysulfate used in the agricultural soil of Bangladesh have been analyzed by gamma spectrometry using a high purity germanium (HPGe) detector. In the fertilizer samples, 226Ra ranged from 4.8 ± 0.8 to 323.8 ± 24.4 Bq kg−1, 228Th ranged from 3.4 ± 1.7 to 22.0 ± 2.8 Bq kg−1, and 40K ranged from 7.9 ± 2.4 to 12628.5 ± 169.0 Bq kg−1. The ratio of radium to thorium was determined, the 226Ra/228Th ratio ranged from 0.237 to 18.69. This study could be useful as baseline data for radiation exposure to fertilizers, and their impact on human health.