Improved methods for elemental analysis of atmospheric aerosols for evaluating human health impacts of aerosols in East Asia

This paper provides improved elemental analysis methods for the characterization of atmospheric particulate matter (PM) samples. With the aim of developing an approach for comprehensive trace element analysis of small mass of PM samples, we coupled an enhanced microwave-assisted acid digestion method with high-resolution magnetic sector inductively coupled plasma-mass spectrometry (SF-ICP-MS). We also propose a rapid and simple method using energy dispersive X-ray fluorescence spectrometry (EDXRF) that has secondary targets and three-dimensional polarization optics for screening elemental composition of PM. We obtained the concentrations of 44 elements ranged from 10^-3 to 10⁵μg/g by SF-ICP-MS, and 16 elements ranged from 10¹ to 10⁵μg/g by EDXRF. The analytic results obtained by these two methods agreed well. Comprehensive analysis for a large set of elements was demonstrated by using the improved SF-ICP-MS method, while EDXRF coupled with fundamental parameter (FP) quantification method can analyze several selected elements as fast as 900s (15min) per sample with only minimal sample pretreatment. We provide two possible choices of analysis methods for elucidating elemental composition of PM according to the number of samples, target elements, sample amounts, time and cost for analysis required.