Distribution of primordial radionuclides in phosphate fertilizers and rock deposits of Pakistan
Abstract
Gamma emitting radionuclides due to 40K, 226Ra and 232Th in different domestic as well as imported phosphate containing fertilizers used in Pakistan, have been determined. For measurement, analysis and data acquisition a high purity germanium detector and PC based MCA was used. The measured values of the specific activity due to 226Ra were found to be very high and varied from 307.7 to 617.5 Bq.kg-l. The minimum and maximum values of the radium equivalent activities for different brands of phosphatic fertilizers resulting from all the three detected gamma emitting radionuclides were estimated to be 338.8 Bq.kg-1 and 929.8 Bq.kg-1 respectively. This enhanced level of radioactivity can cause a significant radiation exposure if these fertilizers are handled in places with poor ventilation system and consequently can lead to radon accumulation. Moreover, this data can also be utilized to assess hazards of radioactivity being spread along with phosphate containing fertilizers in soil during various agricultural processes.
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