Characterisation of atmospheric semi-volatile organic compounds

Atmospheric semi-volatile organic compounds (SVOCs), including polycyclic aromatic hydrocarbons (PAHs), are ubiquitous environmental pollutants, which may be present in the gaseous phase and adsorbed onto the surface of aerosol particles. A novel portable miniature denuder consisting of two multi-channel silicone rubber traps separated by a quartz fibre filter has been developed for such applications. It allows for the concentration of SVOCs in each phase to be determined, which is important for human health risk assessments. The overall particle transmission efficiency through thedenuder was found to be 92 ± 4% for particles between 16 and 320 nm. SVOCs in the traps (gas phase) or on the filter (particle phase) are analysed by GC-MS, or by GCxGC-MS for enhanced separation capability. This enhances detection limits and allows for lower sampling flow rates and shorter sampling times. These denuders have been applied in studies involving the monitoring of emissions from domestic fires, vehicles and underground mine diesel engines