Multi-element analysis of airborne particulate matter by various spectrometric methods after microwave digestion

A microwave digestion procedure in combination of the measurement of various spectrometric methods including atomic absorption spectrometry, inductively coupled plasma atomic emission spectrometry and inductively coupled plasma mass spectrometry was developed for the multi-element analysis of airborne particulate matter collected on PTFE filters by a dichotomous sampler. In order to achieve more sensitive and rapid multi-element analyses, special PTFE-lined digestion vessels were used. It was found that complete digestion of airborne particulates with an acid mixture of HNO₃-HClO₄-HF (3:7:1, v/v) can be achieved in the microwave-irradiated closed vessel system and direct spectroscopic measurement of the digested sample after appropriate dilution. A recovery study was conducted using a multi-element standard and NIST Standard Reference Material 1648 Urban Particulate. Sixteen major, minor, and trace elements in airborne particulate matter were determined.