In the current study, Proton Transfer Reaction-Time of Flight-Mass Spectrometry (PTR-ToF-MS) was used to measure HCN emission factors from the exhaust of individual diesel, biodiesel and gasoline vehicles. Despite its potential health impacts, vehicular HCN emissions estimates and their contribution to regional budgets are highly uncertain. Hydrogen cyanide (HCN) is considered a marker for biomass burning emissions and is a component of vehicle exhaust.
