RAPID: Measuring Volatile Organic Compounds (VOC) Composition During and After the 2025 Los Angeles Wildland-Urban Interface Fires

This RAPID project will provide important information on the local air quality associated with recent fires in Los Angeles. The Eaton and Palisades fires that broke out in early January have been labeled the second and third most destructive fires on record in California. Residents in these areas continue to face uncertainty as to how air quality during and after these fires has impacted their health.

The work will provide timely information to the residents of these areas on their air quality during the fires and offer general insight into the potential health impacts of fires like these that occur at the wildland urban interface.

The objectives of this project are to: (1) Investigate the impact of the Palisades and Eaton Fires on the concentrations of volatile organic compounds (VOC) in the Los Angeles area, and (2) Develop a process-level understanding of VOC persistence in indoor spaces following a wildland urban interface fire. A suite of research-grade instrumentation was deployed on the roof of UCLA’s Young Hall from January 11-30, 2025, during an intense phase of the Eaton and Palisades fires.

The site is approximately 6 miles from the Palisades fire and 20 miles from the Eaton Fire. These data will be used to identify signatures of emissions from fires and burn areas, examine differences as compared to typical biomass burning emissions, assess correlations between VOC concentrations and more typical metrics of air quality, and use a photochemical box model to assess potential impacts on ozone production during and after the fires.

A set of follow-up measurements will be performed 1-year later in the same location with the same instrumentation to serve as a baseline for comparison of smoke-impacted measurements. Samples of common household materials will be collected from several smoke-impacted homes in the Pacific Palisades and Altadena neighborhoods of Los Angeles, as well as similar materials from homes in less-impacted areas of Los Angeles.

VOC off-gassing will be measured under controlled conditions to assess how individual materials and surfaces contribute to the lingering effects of VOC partitioning on indoor air after a fire. The project will provide full support for a graduate student.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.