Emissions of particulate associated oxygenated and native polycyclic aromatic hydrocarbons from vehicles powered by ethanol/gasoline fuel blends

The results showed greatly increased emissions of both OPAHs and PAHs at cold engine start conditions (−7 °C in the NEDC) compared to warm engine start (+22 °C in the ADC). For the OPAHs, higher average total emission factors were obtained when running on E85 compared to E5 at both cold 2.72 µg/km vs 1.11 µg/km and warm 0.19 µg/km vs 0.11 µg/km starting conditions with the highest emissions when using E70 at −7 °C 4.12 µg/km. The same trend was found for the PAHs at cold engine start with higher average total emission factors when using ethanol fuel 71.5 µg/km and 60.0 µg/km for E70 and E85, respectively compared to gasoline E5 (20.2 µg/km). Slightly higher average total PAH emissions were obtained when operating at  +22 °C with E5 compared to with E85 1.23 µg/km vs 0.72 µg/km.