ABSTRACT
Objective To establish an evaluation method of uncertainty for the determination of lead in ambient air PM2.5 by inductively coupled plasma mass spectrometry (ICP-MS). Methods According to HJ657-2013 “Determination of Lead and Other Metal Elements in Air and Exhaust Particulates by Inductively Coupled Plasma Mass Spectrometry”, the concentration of lead in ambient air PM2.5 was determined. A mathematical model was established to analyze the source of uncertainty and to calculate each component of uncertainty. The components were combined into the standard uncertainty, and the relative expanded uncertainty was finally obtained. Results The expanded uncertainty of lead in ambient air PM2.5 was 0.16 ng/m3, and the measurement result of lead was (1.75±0.16)ng/m3. Conclusion The main source of uncertainty of this method comes from the relative standard uncertainty introduced by sample pretreatment.