Levels of 226Ra in groundwater samples collected in Phu Yen province, Vietnam associated with health risks to local population and impacts on the maize (Zea mays L.) soil

Groundwater is a major source of drinking water and agricultural water in some regions of the world. However, it contains a high level of 226 Ra that is potentially hazardous to human health and the environment. Normally, the activity concentration of 226 Ra in groundwater is determined to assess the quality of groundwater that can be used as drinking water. There are few studies on the accumulation of 226 Ra in the agricultural soil due to irrigation with groundwater. In this study, levels of 226 Ra were determined on over 60 groundwater samples collected from the public water supply wells in Phu Yen province, Vietnam. Besides assessment of the health risks to population due to drinking groundwater samples, the impact of groundwater irrigation to the maize field in the study area was studied. For this purpose, two chemical fate models were applied and the comparison of their results was performed. Based on the model assessments, we predicted that the present agricultural practices increased the 226 Ra activity concentration in the maize soil, and the level of 226 Ra activity concentration in the topsoil can exceed the recommended level at 11.4 years of the present agricultural practices on the maize soil.