Mathews Gladys, Nagaiah N, Karthik Kumar M B, Ambika M R
Department of Physics, Bangalore University, Bangalore-560056 Karnataka State, India.
J Radiol Prot. 2015 Jun;35(2):447-55. doi: 10.1088/0952-4746/35/2/447. Epub 2015 May 15.
Groundwater samples collected from 96 bore wells in the study area (city of Bangalore) were analysed for concentration of natural uranium using laser-induced fluorimetry. The risk to the population of the region associated with radiological and chemical toxicity of uranium due to its ingestion through drinking water over a lifetime was estimated. The concentration of uranium was found to be in the range 0.136 to 2027.5 μg L(-1) with an average value of 92.42 μg L(-1). In the present study, about 61% of the samples show concentrations of uranium within the safe limit of 30 μg L(-1) as set by the world health organisation. The radiological risk estimated as lifetime cancer risk is in the range 4.3 × 10(-7) to 6.4 × 10(-3) with an average of 2.9 × 10(-4). The chemical toxicity risk measured as lifetime average daily dose is found to range from 0.005 to 75.42 μg kg(-1) d(-1). The reference dose estimated as 1.12 μg kg(-1) d(-1) was used to assess the chemical toxicity. The results indicate that the chemical toxicity due to ingestion of uranium through drinking water is of more concern than the radiological toxicity. The present study, being the first of its kind in this region, will augment the database of uranium in groundwater.
从研究区域（班加罗尔市）的96口水井采集的地下水样本，使用激光诱导荧光法分析了天然铀的浓度。估算了该地区人口因终生通过饮用水摄入铀而面临的放射性和化学毒性风险。发现铀浓度范围为0.136至2027.5μg L⁻¹，平均值为92.42μg L⁻¹。在本研究中，约61%的样本显示铀浓度在世界卫生组织设定的30μg L⁻¹安全限值内。估算的终生癌症风险形式的放射性风险范围为4.3×10⁻⁷至6.4×10⁻³，平均为2.9×10⁻⁴。以终生平均每日剂量衡量的化学毒性风险范围为0.005至75.42μg kg⁻¹ d⁻¹。用作评估化学毒性的参考剂量估算为1.12μg kg⁻¹ d⁻¹。结果表明，通过饮用水摄入铀造成的化学毒性比放射性毒性更令人担忧。本研究作为该地区此类研究中的首例，将扩充地下水中铀的数据库。
