Uranium isotopes in groundwater in Ho Chi Minh City and related issues: Health risks, environmental effects, and mitigation methods

Abstract

Groundwater is regularly used for many purposes, such as drinking and agricultural irrigation systems. Still, it contains high levels of radionuclides (e.g., ²³⁸U, ²³²Th, and ²²⁶Ra) that are potentially hazardous to humans and the environment. In this study, activity concentrations of uranium isotopes were analyzed in 15 groundwater samples taken from 15 bored wells in Thu Duc district, Ho Chi Minh City, Vietnam. Environmental effects of the irrigation system with groundwater on agricultural soil in the study area were assessed by models. It was found that the activity concentrations of ²³⁸U and ²³⁴U in groundwater samples were in the ranges of (13.5-268.7) mBq l^-1 and (20.2-438.3) mBq l^-1, respectively. The ratio ²³⁴U/²³⁸U values were ranged from 1.12 to 2, with an average value of 1.44. Based on the model prediction, 25 years irrigation with the groundwater can inject 94.8 Bq both uranium isotopes in 1 kg topsoil. For investigated groundwater samples, the proposed removal method using K₂FeO₄ removed 74.28% and 81.04% for ²³⁴U and ²³⁸U, respectively.

Keywords: CEMC soil model; HYDRUS-1D model; P100 purolite resin; Potassium ferrate (K(2)FeO(4)).