摘要：In measuring lead isotope ratios by ICP-MS, measurement values will differ from true values due to mass distinction effect. In this study, methods of correcting measurement values obtained by ICP-MS were examined. In the case of measurement values corrected using a correction coefficient, the proportion of the measurement value of a standard solution to a reference value, the correction value was occasionally different from the true value due to random change of sensitivity. When the correction coefficient was calibrated with a standard solution at regular intervals, correction values were obtained at high levels of accuracy, but tended to show gradual separation from true values. On the other hand, calibration by linearization of temporal fluctuation of the correction coefficient resulted in correction values very close to true values, albeit with some variation.
