North America

United States

United States Government Accountability Office (GAO). Report to Congressional Requesters: Biofuels. Challenges to the Transportation, Sale and Use of Intermediate Ethanol Blends | LINK

  • “Ethanol blended gasolines may cause older automobiles to experience higher emissions of some pollutants”.

Proceedings of the National Academy of Sciences (PNAS). Life cycle air quality impacts of conventional and alternative light-duty transportation in the United States | LINK

  • “Scenarios with substantially higher damages than gasoline include corn ethanol (80% increase)”

Proceedings of the National Academy of Sciences (PNAS). Renewable Fuel Standard: Potential Economic and Environmental Effects of U.S. Biofuel Policy | LINK

  • Air quality modeling suggests that production and use of ethanol as fuel to displace gasoline is likely to increase such air pollutants as particulate matter, ozone, and sulfur oxides.

Environmental Protection Agency (EPA). Evaporative Emissions from On-road Vehicles in MOVES2014 | LINK

  • “(In terms of permeation) ethanol was then seen to have a significant effect compared to E0 fuel”.

Coordinating Research Council (CRC) Studies:

  • CRC Project E-65. Fuel permeation from automotive systems | LINK

    • Permeation increase amounts to 65%–ozone formation potential increase amounts to as much as 55%.

  • CRC E-77-2b

  • CRC Project E-65.3

  • CRC E-77 Pilot Study

  • CRC E-77-2c

Stanford University. Examining the temperature dependence of ethanol (E85) versus gasoline emissions on air pollution with a largely-explicit chemical mechanism, Atmospheric Environment | LINK

  • The results suggest that E85’s effect on health through ozone formation becomes increasingly more significant relative to gasoline at colder temperatures due to the change in exhaust emission composition at lower temperatures. Acetaldehyde and formaldehyde concentrations are also much higher with E85 at cold temperatures, which is a concern because both are considered to be carcinogens. These could have implications for wintertime use of E85.

Eastern Research Group (ERG). Impact of new fuel specifications on vehicle emissions in Mexico | LINK

  • Results show an increase in total motor vehicle VOC emissions of 13-18 percent in metropolitan areas and a 23 percent increase in other areas of the country for NOM-016 compliant E10 fuel, relative to fuel sold in Mexico prior to the NOM-016 update.