The World Health Organisation highlights that 99 % of the global pollution breathe air that exceeds guidelines. Exposure to poor air quality is associated with an estimated 3 million deaths per year. Particulate matter (PM) or aerosol, is the most damaging air pollutant to human health. Organic aerosol, formed primarily from the oxidation of volatile organic compounds, dominates the mass of PM less than 2.5 micrometres (PM2.5).
Organic aerosol represents an extremely complex mixture of organic compounds, with more than 10,000 different species identified across different chemical functionalities. This complexity raises multiple issues, both in terms of organic aerosol analysis and understanding health implications of exposure. To overcome these challenges, my research focuses on improving our ability to identify and quantify individual constituents of organic aerosol and linking this to the health implications of different sources of organic aerosol.
To analyse organic aerosol, we use liquid chromatography coupled to electrospray ionisation high resolution mass spectrometry (LC-ESI-HRMS). This technique allows the separation and detection of many organic molecules, within complex samples. We have developed several methodologies to improve the quantification of organic molecules, including the measurement of matrix effects and the prediction of response factors.
We have developed an atmospheric flow reactor to generate large amounts of atmospherically relevant organic aerosol from different volatile organic compound precursors. The analysis of these samples allows for generated compounds to be used as fingerprints when analysing ambient samples collected around the world. This improves our ability to investigate the sources of different compounds within complex ambient samples.
My postdoctoral project is part of a large NERC funded project, HIPTox: Hazard Identification Platform to Assess the Health Impacts from Indoor and Outdoor Air Pollutant Exposures, through Mechanistic Toxicology. This project has the objective of investigating the toxicology of pollution sources with a focus on how common pollutants impact neurological disease and cognitive function. This is a collaborative, cross-disciplinary project between multiple UK institutions, including atmospheric chemists, epidemiologists, and molecular biologists/toxicologists.