Activity concentrations of ²²⁶Ra, ²³²Th, ⁴⁰K, and ¹³⁷Cs in soil samples collected at Mount Rainier National Park and Satsop Nuclear Power Plant zone in State of Washington (USA) and Curonian Spit National Park and Ignalina Nuclear Power Plant zone in Lithuania have been measured by gamma spectrometry. The results have been compared with the worldwide measured average values reported by the UNSCEAR. Higher activity concentrations of ¹³⁷Cs were found in Curonian Spit National Park due to Chernobyl accident fallout. The radium equivalent activity (Ra_eq), the external hazard index (H_ex), the internal hazard index (H_in), the absorbed dose rate (D), and the annual effective dose rate (AEDR) were also calculated and compared with the international recommended values. These calculated hazard indices used to estimate the potential radiological health risk in soil and the dose rate associated with it are below their permissible limit.

中文翻译：

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华盛顿州（美国）和立陶宛特定地区土壤中天然和人工放射性核素引起的辐射背景的比较评估

在美国华盛顿州的雷尼尔山国家公园和萨索普核电站区域以及立陶宛的库尔斯沙嘴国家公园和伊格纳利纳核电站区域收集的土壤样品中，土壤中的放射性活度浓度为²²⁶ Ra，²³² Th，⁴⁰ K和¹³⁷ Cs。已经通过γ光谱法测量。将结果与UNSCEAR报告的全球测量平均值进行了比较。由于切尔诺贝利事故的后果，库尔斯沙嘴国家公园发现了更高的¹³⁷ Cs活性浓度。镭当量活度（Ra _eq），外部危害指数（H _ex），内部危害指数（H_在）中，还计算了吸收剂量率（D）和年有效剂量率（AEDR）并与国际推荐值进行了比较。这些计算得出的危害指数用于估算土壤中的潜在放射健康风险以及与之相关的剂量率均低于其允许极限。