title: Effects of Cold Temperature and Ethanol Content on VOC Emissions from Light-Duty Gasoline Vehicles.
abstract: Emissions of speciated volatile organic compounds (VOCs), including mobile source air toxics (MSATs), were measured in vehicle exhaust from three light-duty spark ignition vehicles operating on summer and winter grade gasoline (E0) and ethanol blended (E10 and E85) fuels. Vehicle testing was conducted using a three-phase LA92 driving cycle in a temperature-controlled chassis dynamometer at two ambient temperatures (-7 and 24 °C). The cold start driving phase and cold ambient temperature increased VOC and MSAT emissions up to several orders of magnitude compared to emissions during other vehicle operation phases and warm ambient temperature testing, respectively. As a result, calculated ozone formation potentials (OFPs) were 7 to 21 times greater for the cold starts during cold temperature tests than comparable warm temperature tests. The use of E85 fuel generally led to substantial reductions in hydrocarbons and increases in oxygenates such as ethanol and acetaldehyde compared to E0 and E10 fuels. However, at the same ambient temperature, the VOC emissions from the E0 and E10 fuels and OFPs from all fuels were not significantly different. Cold temperature effects on cold start MSAT emissions varied by individual MSAT compound, but were consistent over a range of modern spark ignition vehicles.
authors.affiliation: Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency , Research Triangle Park, North Carolina 27711, United States.
authors.forename: Ingrid J
authors.initials: IJ
authors.lastname: George
authors.affiliation: Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency , Research Triangle Park, North Carolina 27711, United States.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Hays
authors.affiliation: Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency , Research Triangle Park, North Carolina 27711, United States.
authors.forename: Jason S
authors.initials: JS
authors.lastname: Herrington
authors.affiliation: ARCADIS U.S., Inc. , Research Triangle Park, North Carolina 27711, United States.
authors.forename: William
authors.initials: W
authors.lastname: Preston
authors.affiliation: Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency , Research Triangle Park, North Carolina 27711, United States.
authors.forename: Richard
authors.initials: R
authors.lastname: Snow
authors.affiliation: Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency , Research Triangle Park, North Carolina 27711, United States.
authors.forename: James
authors.initials: J
authors.lastname: Faircloth
authors.affiliation: Office of Research and Development, National Health and Environmental Effects Research Laboratory, United States Environmental Protection Agency , Research Triangle Park, North Carolina 27711, United States.
authors.forename: Barbara Jane
authors.initials: BJ
authors.lastname: George
authors.affiliation: Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency , Research Triangle Park, North Carolina 27711, United States.
authors.forename: Thomas
authors.initials: T
authors.lastname: Long
authors.affiliation: Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency , Research Triangle Park, North Carolina 27711, United States.
authors.forename: Richard W
authors.initials: RW
authors.lastname: Baldauf
mesh_terms: D001334:Automobile Driving; D003080:Cold Temperature; D000431:Ethanol / Q000032:analysis*; D005742:Gasoline / Q000032:analysis*; D018986:Motor Vehicles; D010126:Ozone / Q000032:analysis; D013696:Temperature; D001335:Vehicle Emissions / Q000032:analysis*; D055549:Volatile Organic Compounds / Q000032:analysis*
chemical_list: D005742:Gasoline; D001335:Vehicle Emissions; D055549:Volatile Organic Compounds; D000431:Ethanol; D010126:Ozone