ABSTRACT

Natural radioactivity in soil, rock, building materials, and water is very important for the radiological protection point of view. Radon is one of the carcinogenic radioactive gases. Radon causes radiological risk to the public via ingestion and inhalation. The ²²²Rn activity concentrations were estimated in potable water of Uttara Kannada district (Coastal region) using the Emanometry technique. Radon activity levels were found to vary from 2.37 ± 0.19 Bql⁻¹ to 171.35 ± 1.96 Bql⁻¹ with a mean value of 22.62 ± 0.82 Bql⁻¹. The majority of the radon levels are within the reference level of 100 Bql⁻¹ proposed by WHO and EU Commission. Nearly 55% of the potable water had radon activity levels exceeds the MCL of 11.1 Bql⁻¹ proposed by USEPA. The annual average ingestion dose values are lower than the action level of 100 µSvy⁻¹ as proposed by WHO and EU Commission. The activity concentration of ²²⁶Ra, ²³²Th, and ⁴⁰K in soil were estimated by using NaI(Tl) detector-based gamma-ray spectrometry. The average activity of ²²⁶Ra, ²³²Th, and ⁴⁰K in soil samples is 36.12, 50.45, and 315.35 Bq kg⁻¹, respectively, and the activity concentration of ²²⁶Ra and ²³²Th is slightly higher than the world average. The calculated radiological hazards are well within the world average value.

摘要

在土壤，岩石，建筑材料和水中的自然放射性对于放射防护的观点非常重要。on是致癌的放射性气体之一。on通过摄入和吸入对公众造成放射风险。在^222种Rn中的活性浓度使用Emanometry技术在郁多埃纳德语区（海岸区域）的饮用水估计。发现活度水平从2.37±0.19 Bql ^-1变化至171.35±1.96 Bql ^-1，平均值为22.62±0.82 Bql ^-1。大部分the水平在100 Bql ^-1的参考水平内由世界卫生组织和欧盟委员会提出。饮用水中近55％的ra活度超过了USEPA提出的11.1 Bql ^-1的MCL 。年平均摄入剂量值低于WHO和EU委员会建议的100 µSvy ^-1的作用水平。通过使用基于NaI（Tl）探测器的伽马射线光谱法估算土壤中²²⁶ Ra，²³² Th和⁴⁰ K的活性浓度。土壤样品中²²⁶ Ra，²³² Th和⁴⁰ K的平均活性分别为36.12、50.45和315.35 Bq kg ^-1，并且²²⁶ Ra和²³²的活性浓度Th略高于世界平均水平。计算得出的放射危害完全在世界平均值范围内。