Agenda

Speakers:
Chiara Giorio - Department of Chemistry, University of Cambridge (UK)
Yusuf Hamied - Department of Chemistry, University of Cambridge (UK)

Abstract:
About 0.2% of the Earth’s water is in the atmosphere. Rain, fog, clouds, and deliquescent aerosols create a water phase that can shift the reactivity of volatile and non-volatile species, forming new products that would not otherwise form in gas-phase reactions. A notable example of processes promoted by aqueous environments is coordination chemistry. Such a process leads to the formation of metal-ligand complexes between different species in the aerosols, thereby increasing the solubility of particle-bound metals, their bioavailability, and altering their capacity to generate reactive oxygen species. We investigated metals' reactivity, including the formation of metal-organic ligand complexes, in urban aerosol collected in the city centre of Padua, in the Po Valley (Italy), in marine aerosol from a remote coastal environment in Henties Bay (Namibia), in volcanic aerosol collected from the summit of Mt Etna (Italy), and in non-exhaust emissions from passenger cars. We assessed the effects of metal-ligand complexes formation on the solubility and solubilisation kinetics of metals from the particles to both fog waters and a surrogate lung fluid. We observed contrasting solubilities and dissolution kinetics in the two aqueous environments studied, as well as different aqueous-phase reactivities across the locations. We exposed pulmonary cells to metals in different chemical forms to assess their toxicity, determine their oxidative potential, and assess their ability to promote protein aggregation linked to the development of neurodegenerative diseases.

Bio sketch:
Professor of Atmospheric Chemistry Yusuf Hamied Department of Chemistry, University of Cambridge (UK); Group leader of an interdisciplinary research team of 17 people of which 5 Postdoctoral Research Associates, 1 Research Assistant, and 11 Postgraduate students - Visiting Scholar presso il Dipartimento di Scienze Ambientali, Informatica e Statistica Università Ca' Foscari Venezia