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Uranium is a naturally occurring radioactive element which may cause toxicological or radiological hazards to the public if present in drinking water. This study reports the quantification of uranium in groundwater of major towns of the district Fatehabad, Haryana, India. Uranium concentrations ranged between 0.3 and 48 μg L?1. In 22% of the groundwater samples, uranium concentrations were higher than the World Health Organization maximum permissible limit of 30 µg L?1. The radiological dose for males was found to be in the range of 4.8?×?10?4–7.1?×?10?2 mSv y?1 and for females 3.5?×?10?4–5.2?×?10?2 mSv y?1. The results showed that due to the ingestion of groundwater in the study area, radiological cancer risk is in the range of 9.1?×?10?7–1.3?×?10?4, lower than the risk limit. Uranium ingestion from groundwater varied from 0.02 to 3.5 µg kg?1 day?1, which is within acceptable limit.  相似文献   
2.
The best groundwater resources in Finland are generally situated in glaciofluvial formations with thick sand and gravel deposits. The glaciofluvial formation of Jokkavaara, in northern Finland near the town of Rovaniemi, is important for both its groundwater reserves and its sand and gravel resources. The groundwater and mineral resources of Jokkavaara was studied to define their quantity and quality, and to develop a land-use plan which would help civil servants of the municipality to make the decisions necessary for exploiting sand and gravel. The land-use plan shows the areas where exploiting mineral resources is not allowed or recommended because of the risks of contamination of groundwater, or because of injurious effects on the environment caused by noise and dust from gravel pits, or by spoilt landscape. The size of Jokkavaara is 5 km2, and its mineral resources are about 53 million cubic metres. The sand and gravel deposits are at the most, 50 m thick. Risks of contamination by fallout are small, due to the thick sand and gravel deposits above groundwater level. Exploiting mineral resources have no effect on groundwater quality either. By the land-use plan and legislation, good groundwater can also be protected in the future. Legislation limits the exploitation of mineral resources especially in groundwater areas.  相似文献   
3.
The uptake of naturally occurring uranium, thorium, radium and potassium by wheat plant from two morphologically different soils of India was studied under natural field conditions. The soil to wheat grain transfer factors (TF) were calculated and observed to be in the range of 4.0 x 10(-4) to 2.1 x 10(-3) for 238U, 6.0 x 10(-3) to 2.4 x 10(-2) for 232Th, 9.0 x 10(-3) to 1.6 x 10(-2) for 226Ra and 0.14-3.1 for 40K. Observed ratios (OR) of radionuclides with respect to calcium have been calculated to explain nearly comparable TF values in spite of differences in soil concentration of the different fields. They also give an idea about the discrimination exhibited by the plant in uptake of essential and nonessential elements. The availability of calcium and potassium in soil for uptake affects the uranium, thorium and radium content of the plant. The other soil factors such as illite clays of alluvial soil which trap potassium in its crystal lattice and phosphates which form insoluble compounds with thorium are seen to reduce their availability to plants. A major percentage (54-75%) of total 238U, 232Th and 226Ra activity in the plant is concentrated in the roots and only about 1-2% was distributed in the grains, whereas about 57% of 40K activity accumulated in the shoots and 16% in the grains. The intake of radionuclides by consumption of wheat grains from the fields studied contributes a small fraction to the total annual ingestion dose received by man due to naturally existing radioactivity in the environment.  相似文献   
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