Post-Wildfire Indoor Pollution in WUI Areas following the 2025 Los Angeles Fires. Part I. Establishing Baseline Contaminant Levels Prior to Home Reoccupation.

ABSTRACT: Wildland-urban interface (WUI) fires pose unique environmental pollution challenges due to the combustion of both natural vegetation and synthetic building materials. Following the 2025 Palisades and Eaton wildfires in Los Angeles, we conducted a field study to characterize indoor air quality and surface contamination in 19 homes before reoccupancy. Indoor PM_2.5 and PM₁₀ concentrations averaged 3.45 and 31.66 μg/m³, respectively, with several homes showing indoor-to-outdoor (I/O) ratios of >1 (particularly for PM₁₀) compared to typical I/O values of 0.45-0.8 in residences, indicating persistent indoor particle reservoirs. Depending on the air-exchange rate, elevated indoor PM levels in noncleaned homes may arise from two contrasting mechanisms: l

SUBMITTER: Goftari E 

PROVIDER: S-EPMC12797226 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature