Analyses of radioactivity concentrations in soil and assessment of effective doses in several districts of Banten and West Java, Indonesia

Radioactivity concentration in soil was analyzed around the capital city of Indonesia, Jakarta along with the adjoining provinces of West Java and Banten, representing one of the most densely populated in Indonesia. Nestled within this area is a nuclear research reactor. The analysis of natural and artificial radioactivity concentrations using a HPGe gamma spectrometry to measure 226Ra, 232Th, 40K, and 137Cs in surface soil samples. The results indicate that the average activity concentrations of 226Ra, 232Th, and 40K ranged from 18 to 49, 24 to 74, and 18 to 249 Bq/kg, respectively. The calculated value for the total average absorbed dose rate in the air in Banten and West Java is 38 ± 4 and 34 ± 4 nGy/h. Nonetheless, the calculated value of the external hazard index indicates that the soils in that region are deemed suitable for use in construction materials, and the area is safe for habitation. The activity concentrations of 137Cs in several districts of Banten and West Java ranged from <0.09 to 0.73 Bq/kg. Even a minor introduction of artificial radioactivity into the environment constitutes a form of pollution that must be closely monitored as a potential environmental threat.