Evaluation of combustion products in air from electric and internal combustion engine vehicles during full-scale fire experiments

The combustion of vehicles generates fire effluent that may contain compounds that pose unique health hazards. This study evaluated the composition of products of combustion that may present chronic health concerns from electric vehicles (EVs) and internal combustion engine vehicles (ICEVs). Six EVs and three ICEVs were ignited with a 30 kW burner and allowed to burn until all combustible components of the entire vehicle were consumed. Active and passive air samplers were deployed 3.0 m in front of and 4.5 m behind the vehicle’s bumpers, and in the smoke plume 8.7 m above the vehicle. Combustion gases were sampled for volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), heavy metals, acid gases, per- and polyfluoroalkyl substances (PFAS), and inhalable particulates. EVs and ICEVs burned for similar durations, though EVs took longer to initially catch fire with this particular ignition method. Acid gases, VOCs, PFAS, PAHs, and inhalable particulates in the smoke showed minor differences between the vehicle types, though fluoride particulate was notably greater in the EV fires. Greater amounts of heavy metals (specifically nickel, manganese, cobalt, and lithium) were detected in the EV fire effluent relative to the ICEVs. Both EV and ICEV fires produce combustion products that could present health hazards to responders or bystanders. • Fires in both types of vehicles produce inhalation and dermal exposure health hazards. • Greater concentrations of some heavy metals produced during electric vehicle fires. • Fluoride particulate was detected in higher concentrations than HF in EV fires. • Fluoride particulate was greater in EV fires than internal combustion vehicle fires.