title: Comparison of emission of dioxins and furans from gasohol- and ethanol-powered vehicles.
abstract: The exhaust emissions of 17 polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) were investigated in two spark-ignition light-duty vehicles, one gasohol-fueled and a flexible-fuel one fueled with hydrated ethanol. Gasohol is a mixture of gasoline and 22% ethanol. The influence of fuel type and quality, lubricant oil type, and use of fuel additives on the formation of these compounds was tested using standardized U.S. Federal Test Procedure (FTP)-75 cycle tests. The sampling of the PCDD/Fs followed the recommendations of a modified U.S. Environmental Protection Agency (EPA) Method 23 ( http://www.epa.gov/ttn/emc/promgate/m-23.pdf ) and the analysis basically followed the U.S. EPA Method 8290 ( http://www.epa.gov/osw/hazard/testmethods/sw846/pdfs/8290a.pdf ). Results showed that emission factors of PCDD/Fs for the gasohol vehicle varied from undetected to 0.068 pg international toxic equivalency (I-TEQ) km-1(average of 0.0294 pg I-TEQ km-1), whereas in the ethanol vehicle they varied from 0.004 to 0.157 pg (I-TEQ) km-1(average of 0.031 pg I-TEQ km-1). In the gasohol-powered vehicle, the use of fuel additive diminished the emission of Octachlorodibenzo-p-dioxin (OCDD) significantly, whereas in the ethanol vehicle no significant associations were observed between the investigated variables and the emissions. [Box: see text].
authors.affiliation: Vehicular Emission Laboratory, Cetesb, São Paulo, Brazil. ruia@cetesbnet.sp.gov.br
authors.forename: Rui
authors.initials: R
authors.lastname: de Abrantes
authors.forename: João V
authors.initials: JV
authors.lastname: de Assunção
authors.forename: Célia R
authors.initials: CR
authors.lastname: Pesquero
authors.forename: Raimundo P
authors.initials: RP
authors.lastname: da Nóbrega
authors.forename: Roy E
authors.initials: RE
authors.lastname: Bruns
mesh_terms: D000397:Air Pollution; D004147:Dioxins / Q000032:analysis*; D004784:Environmental Monitoring; D000431:Ethanol / Q000032:analysis; D005663:Furans / Q000032:analysis*; D005742:Gasoline / Q000032:analysis; D006801:Humans; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D004147:Dioxins; D005663:Furans; D005742:Gasoline; D001335:Vehicle Emissions; D000431:Ethanol