Evaluation of Measurement Uncertainty in Waste Cadmium Analysis

This study used inductively coupled plasma optical emission spectrometry to evaluate the uncertainty associated with measuring the cadmium content in waste sample. In this study, the uncertainty factors were divided into acid digestion, standard solutions for calibration curve, calibration curve, and repeated measurement. The cadmium content was determined to be 109.12 ± 3.60 mg/kg. In addition, it had a significant impact on the uncertainty in the calibration curve and the standard solutions for constructing the calibration curve. The uncertainty in the calibration curve can be reduced by increasing the concentration of the standard solution, as proposed in previous studies. In addition, to reduce the uncertainty that arises from preparing standard solutions, an alternative would be to pipette the liquid as the weight corresponding to the target volume instead of the volume itself.