Health risk assessment of natural uranium in ground water of Bangalore, India

Water is one of the universal substances, which is used alike by mankind to sustain life. Drinking water comes from surface and ground water sources which may become contaminated due to anthropogenic activities or due to the presence of chemical elements present in it. The concentration of uranium in ground water depends on the lithology, geomorphology and other geological conditions of the region. Uranium has both chemical and radiological toxicity with the two important organs being the kidneys and lungs. Uranium nuclides emit high energy alpha rays and therefore they are hazardous if inhaled or ingested in higher quantity. According to an estimate food contributes about 15% of ingested uranium while drinking water contributes 85%. About 26% of the samples showed values of effective dose, higher than the recommended level of 100μSv/y (WHO). The correlation between the measured concentration of uranium and the physicochemical parameters of the water samples were also studied. Attempts will also be made to understand the observed trend of variation in the concentration of uranium with the geology of the study area. The main objective of the present study is to measure the level of uranium in drinking water samples and to assess the annual effective dose due to the ingestion of uranium from the health hazard point of view. The physicochemical parameters of water samples were also measured to find the correlation if any with the measured U concentration