Atmospheric particulate pollution has been linked to a broad spectrum of adverse health effects including respiratory problems, cardiovascular diseases, cancer and dementia. These effects depend not only on physical, but also on chemical properties of airborne particulate matter (PM) though to date it has proven difficult to disentangle the relative contribution of PM constituents to the reported population-level health effects. To address this issue this project will use ‘tailored’ reference aerosols, combined with high-resolution optical imaging of exposed cells and state-of-the-art cell analysis methods to study the cytotoxic effects of airborne PM in vitro. This will be done in a systematic way to help inform which PM metrics are associated with the induction of toxic mechanisms so that they can then be linked to specific health effects.