Wildland–urban interface co-combustion of biomass, synthetic polymeric materials, and lithium-ion batteries generates a new class of ultrafine soot–metal–PAH hybrid particles

Wildland–urban interface (WUI) fires increasingly involve the co-combustion of biomass with synthetic polymers such as polystyrene (PS) and lithium-ion batteries (LIBs); yet the resulting particulate emissions, including ultrafine particles (≤0.1 μm), remain insufficiently quantified and mechanistically unresolved. Here, we present a size- and chemistry-resolved analysis of particulate matter (...