Abstract An extensive pioneer study was conducted to determine the activity concentration of 238U and 232Th in 94 groundwater samples to examine the influence of geological formations on the activity concentrations of 238U and 232Th and to investigate a relationship with the major chemical elements in groundwater. The study also aims to estimate the annual effective dose and health impact due to the intake of these radionuclides in the groundwater of Jordan. The mean activity concentrations of 238U and 232Th in groundwater were found to be 33 ± 5 mBq L−1 and 0.017 ± 0.002 mBq L−1, respectively. The highest mean of 238U and 232Th activity concentrations were found for lower Cretaceous geological formation, while Tertiary and Quaternary geological formations have the lowest mean 238U and 232Th activity concentration, respectively. The output of (ANOVA) and post hoc tests revealed the existence of significant influence of geological formations on 238U activity concentrations, while insignificant influence on 232Th activity concentrations was found in the groundwater of Jordan. The groundwater of Jordan was dominated by HCO3−1, Cl−1, Ca+2, and Na+1. The mean annual effective dose due to the ingestion of radionuclides 238U and 232Th in groundwater were found 1.143 μSv lower than recommended by WHO. The ingestion dose deduced is dominated by 238U of 99% where the average contribution from 232Th amounted to 1%. The results of the study will serve as a baseline data of 238U and 232Th activity concentrations in groundwater based on geological formations of Jordan.

中文翻译：

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约旦地下水中的 238U 和 232Th 同位素：地质影响、水化学和健康影响

摘要 开展了一项广泛的先驱研究，测定了94个地下水样品中238U和232Th的活度浓度，以检验地质构造对238U和232Th活度浓度的影响，并研究与地下水中主要化学元素的关系。该研究还旨在估计由于在约旦地下水中摄入这些放射性核素而造成的年有效剂量和健康影响。发现地下水中 238U 和 232Th 的平均活性浓度分别为 33 ± 5 mBq L-1 和 0.017 ± 0.002 mBq L-1。238U 和 232Th 活动浓度平均值最高的是下白垩统地质地层，而第三纪和第四纪地质地层的 238U 和 232Th 活动浓度平均值分别最低。(ANOVA)和事后检验的结果表明，地质构造对238U活动浓度存在显着影响，而在约旦地下水中发现对232Th活动浓度影响不显着。约旦地下水以 HCO3-1、Cl-1、Ca+2 和 Na+1 为主。发现由于摄入地下水中放射性核素 238U 和 232Th 引起的平均年有效剂量比 WHO 推荐的低 1.143 μSv。推断的摄入剂量以 238U 为主，占 99%，其中 232Th 的平均贡献达 1%。研究结果将作为基于约旦地质构造的地下水中 238U 和 232Th 活动浓度的基线数据。