Assessment of radioactivity concentration in intertidal sediments from coastal provinces in Oman and estimation of hazard and radiation indices.

Abstract The natural radioactivity of intertidal sediment samples collected from the beaches of Oman was investigated. Using gamma ray spectrometry, the activity concentrations of 226Ra, 232Th and 40K in the sediment samples were measured to have average values of 20.49 ± 3.50, 2.26 ± 0.60 and 44.83 ± 4.60 Bq kg−1 respectively. The activity levels reported are considerably lower than the worldwide average. The annual effective dose rate was estimated to be 0.015 mSv yr−1 on average. Additionally, the mean radium equivalent, external and internal indices were 26.89, 0.07 and 0.13 Bq kg−1 respectively which were well below the risk limits. Gamma and alpha radiation indices were computed to be less than unity and show no exceedance beyond the recommended level. Our results provide baseline data for radioactivity in intertidal sediment samples of Oman and show that intertidal beach sand does not pose significant radiological risk to human health.