Determination of uranium concentrations and isotopic ratios in drinking water in Xilingol League of Inner Mongolia by ICP-MS

Objective To ascertain the uranium concentrations and uranium isotopic ratios in drinking water in Xilingol League,the Inner Mongolia Autonomous Region.Methods Drinking water samples were collected in Xilingol League,the Inner Mongolia Autonomous.Region inductively coupled plasma mass spectrometry (ICP-MS) was applied to determine the concentration of uranium and uranium isotope abundance.Results The uranium concentrations in all samples were in the range of 2.73-18.9μg/L,with an average of 8.20 μg/L.Tbe234U/238U isotope ratio varied from 7.513 × 10-5to 3.003 × 10-4 and235U/238U from 7.196 × 10-3 to 7.391 × 10-3.The relative standard deviation (RSD) was less than 0.5％ for234U/238U and 0.2％ for235 U/238U.Conclusions The uranium concentration in samples collected from Dongwuqi was high than 15 μg/L,whih is the limit given by World Health Organization (WHO).The uranium in drinking water originates from the natural environment.The234U is enriched in drinking water. Key words: Uranium;  Inductively coupled plasma mass spectrometry (ICP-MS);  Isotope ratios ;  Drinking water