Health Effects of Airborne Contaminants
Despite decades of research on air pollution impacts, there is a critical gap in our understanding of how exposure to air pollution affects cellular responses and key biological pathways. Resolving this gap is not an esoteric exercise, as remediation requires focus on the components of pollution that are most influential in driving effects.
Effect of particle size on health impacts of aerosols
While PM2.5 mass concentration is undoubtedly important, there is emerging evidence that smaller particles are more toxic18 and that particle number concentration may be just as impactful as mass concentration. However, a mechanistic understanding linking particle size, composition and biological processes is lacking. For practical reasons, it has been impossible to isolate the effect of particle size alone on health impacts until now. We explore a range of combustion sources including gasoline direct injection (GDI) engines, diesel engines, wood fires and cannabis smoke. smoke. Parallel chemical and physical characterization of the size-selected aerosols (Aerodynamic Aerosol Classifier) and gases using a high-sensitivity Proton-Transfer-Reaction Time-of-Flight Mass Spectrometer (PTR-ToF-MS). particles changed. The effects of particle size on markers of health is investigated using cellular exposure experiments with the CULTEX Cell Culture Exposure System. The CULTEX deposits aerosol particles on commercially available bronchial epithelial cell lines for characterization of cellular responses.
Response of airway epithelium exposed to photochemically-aged air pollution
The emissions from distant sources, transported over days to weeks, undergo physical and chemical changes (or “aging”) due to photochemistry, cloud processing and partitioning. The question addressed in this program is whether the aged emissions are significantly more toxic than ‘fresh’ emissions. We use a Potential Aerosol Mass (PAM) Oxidation Reactor to artificially age traffic related air pollution (TRAP). PM from both standard and aged TRAP will be characterized using RAIN reference instruments and collected on Teflon filters to determine the oxidative potential and organic content of the PM. The PTR-ToF-MS will be used to quantify the volatile fraction of the organic aerosols.