Sediment distribution of Ra-226 and Ra-228 in the East Coast of Peninsular Malaysia

Sediment samples were collected at 17 sampling points in the east coast of Peninsular Malaysia within 2017 until 2018. The purposes of this study were mainly to quantify availability and distribution of Ra-226 and Ra-228 and its ratio in marine surface sediment around the east coast of Peninsular Malaysia. All samples were counted using high- purity germanium (HPGe) spectrometer after 30 days of secular equilibrium to quantify the activity concentrations of those radionuclides. The activity concentrations of Ra-226 and Ra-228 and its ratios were varied with the ranges of 5.6 Bq/kg dw. to 64.9 Bq/kg dw., 8.3 Bq/kg dw. to 42.2 Bq/kg dw., and 0.61 to 2.39, respectively. However, there were found to be comparable to previous studies and even lower than other regions. Thus, it can be confirmed that these radionuclides were mainly supplied and transported from terrestrial sources. It also can be concluded that the factors affected the availability and distribution of these radionuclides and its ratio were strictly related to their half-life, other potential input sources, geological formation of the study area, environment origin and behaviour.