Excess lifetime cancer risk due to natural background radiations of Soil in North Kashmir

Abstract

Background: Long term exposure to environmental radioactivity and the associated external exposure due to gamma emitting radionuclides have serious health effects particularly on cancer risk. Of course, the soil radioactivity depends on the underlying rocks and consequently, the soil type and the geographic conditions. Objectives: Evaluation of excess life time cancer risk due to natural radioactivity of the soil of surface layer of the Nichahoma lignite belt and the soil of villages surrounding the lignite belt. 226 232 40 Methods: In this particular study, stirring radionuclides of the Ra , Th , and K present in the soil samples of the lignite belt and soil of the villages surrounding the lignite belt were measured by using a low-background Pb-shielded gamma spectroscopic counting assembly utilizing NaI(Tl) detector for the measurement and to evaluation the radiation hazard indices and excess life time cancer risk. -3 -3 -3 -3 Results: The excess life time cancer ranged from 0.65×10 to 0.71× 10 (average ~0.68×10 ) for the soil of the lignite belt and from 1.15×10 to -3 -3 1.34×10 (average ~1.25×10 ) for the soil of the villages surrounding the belt. The correlation analyses, performed between the radium equivalent activity and excess life time cancer risk for the two types of the sample, showed very strong and linear dependence of excess life time cancer risk on radium equivalent activity and measured dose rate for the soil of the lignite belt compared to the soil of the villages surrounding the lignite belt. Conclusion: Compared to world average, the average value of computed excess life time cancer risk for both the categories of investigated samples in the study was found to be higher than 0.29. JMS 2018: 21 (2):101-108 Keyword: Excess life time cancer risk, measured dose rate, radium equivalent activity, correlation analysis, lignite belt.