In situ measurement of terrestrial gamma dose rates in eastern region of Peninsular Malaysia and its relation to geological formation and soil types (original) (raw)

This present study aims to obtain baseline data of environmental terrestrial radiation and to assess the corresponding health risk in the ambient environment in eastern region of Peninsular Malaysia. The measurements were taken 1 m above the soil surface using NaI [Ti] detector with a total of 2144 measured points which covered all geological formations and soil types. The measured gamma dose rates ranged from 26 nGy h−1 to 750 nGy h−1 with a mean value of 172±90 nGy h−1. The mean gamma dose rate is three times higher than world averages of 57 nGy h−1. The data of gamma dose rates show the reading of the gamma dose rates not fit to the normal distribution. The variations of gamma dose rates based on geological formation and soil types were investigated using the unbalanced one way ANOVA. The results indicated strong significant differences due to the different geological formations and soil types. The T-test of gamma dose rates for each pair of soil types or geological formations an...