Metals and metalloids analysis by GED-SP-ICP-MS in airborne particles

Metals and metalloids are commonly found in airborne particulate matter (PM) and originate from a wide range of sources, including vehicular emissions, mineral dusts, biomass burning, etc. Many of these metals and metalloids are toxic and carcinogenic, hence the importance of measuring their concentrations in the air. The composition of PM also provides information about emission sources. However, most studies focus on the total elemental composition in bulk samples, rather than the precise composition of the individual particles. This approach relying on digestion of collected PM results in the loss of information about individual particles. Single-particle inductively coupled plasma mass spectrometry (SP-ICP-MS) allows a quantitative measurement of individual nano-and microparticles. Typically, PM are collected and dispersed in water, allowing the elemental composition of individual particles to be determined.
One of the limitations that the water-dispersed environmental PM sampling encountered in typical SP-ICP-MS is that airborne particles are subjected to transformation in aqueous dispersion. As a result, some particles may be altered or lost during sample preparation. To overcome this limitation, a gas exchange device SP-ICP-MS (GED-SP-ICP-MS) method is under development, allowing the analysis of particles directly in aerosol. Only a limited number of studies have used SP-ICP-MS to study airborne samples. To enable the use of this technique for environmental analysis purposes, we are proceeding with the validation and exploration of different aerosol sampling methods combined with the GED-SP-ICP-MS. Using nanoparticles (cerium oxide 200 nm) aerosolized in a sampling bag, it has been shown that the typical transport efficiency normally applied to water-dispersed samples in SP-ICP-MS can be estimated for GED-SP-ICP-MS.