Characterizing the Toxicity of Polycyclic Aromatic Hydrocarbons from Light-Duty On-Road Fuel Emissions in the United States

Abstract

Main Findings: • Health research has found consistent evidence for health impacts from polycyclic aromatic hydrocarbons (PAH), both in terms of ambient concentrations and contribution to the toxicity of particulate matter • Atmospheric chemistry research has identified PAHs as a potentially important contributor to secondary organic aerosol formation, a component of fine particulate matter (PM2.5) • Ethanol blend fuels have been shown to reduce PAH and PM emissions in some studies, but there remains uncertainty as to the overall impact of fuel blending on PAH emissions as a function of blend level • Ambient measurements of PAHs are limited, so computer models of emissions and air quality play an important role in public health assessment