PhD Thesis Defence by Jordina Gili

The predoctoral researcher Jordina Gili, from the EGAR group, will defend her thesis on 2nd December at 11:00h in Aula Eduard Fontserè, Facultat de Física, Universitat de Barcelona.

Directors: Mar Viana and Barend L. van Drooge

Thesis Committee: Brigite Botequim, Amalia Muñoz and Jordi Dachs.

Abstract:
Wildland fires—both wildfires and prescribed burns—are becoming increasingly frequent and intense across Southern Europe due to climate and land-use changes, posing growing threats to air quality and human health. This thesis aims to assess the impacts of smoke emissions on ambient air and firefighters’ personal exposure to fine particulate matter (PM2.5), black carbon (BC), and polycyclic aromatic hydrocarbons (PAHs). Between 2022 and 2024, field monitoring campaigns were conducted in two of Spain’s most fire-prone areas: Galicia (NW Spain) and Catalonia (NE Spain), using a combination of fixed monitors and portable sampling devices. Calibrated monitors revealed substantial PM2.5 increases in ambient air and, combined with source-apportionment tools, enabled high-resolution characterization of wildfire smoke. Firefighters showed high and comparable exposures during wildfires and prescribed burns, supporting the use of prescribed burns as practical proxies for wildfire exposure assessments. Task-based characterization revealed different profiles: mop-up tasks were identified as a relevant contributor to PM2.5 exposures, while torchers were more influenced by fossil-fuel emissions and specific carcinogenic PAHs. BC–PAH correlations indicated that BC may be used as an effective proxy for PAH exposure. Estimated cancer risks exceeded safety thresholds for ignition tasks, supporting the classification of occupational exposure as a firefighter as carcinogenic to humans, highlighting the need for task-specific exposure mitigation strategies.