title: Health assessment of gasoline and fuel oxygenate vapors: subchronic inhalation toxicity.
abstract: Sprague Dawley rats were exposed via inhalation to vapor condensates of either gasoline or gasoline combined with various fuel oxygenates to assess whether their use in gasoline influences the hazard of evaporative emissions. Test substances included vapor condensates prepared from an EPA described "baseline gasoline" (BGVC), or gasoline combined with methyl tertiary butyl ether (G/MTBE), ethyl t-butyl ether (G/ETBE), t-amyl methyl ether (G/TAME), diisopropyl ether (G/DIPE), ethanol (G/EtOH), or t-butyl alcohol (G/TBA). Target concentrations were 0, 2000, 10,000 or 20,000mg/m(3) and exposures were for 6h/day, 5days/week for 13weeks. A portion of the animals were maintained for a four week recovery period to determine the reversibility of potential adverse effects. Increased kidney weight and light hydrocarbon nephropathy (LHN) were observed in treated male rats in all studies which were reversible or nearly reversible after 4weeks recovery. LHN is unique to male rats and is not relevant to human toxicity. The no observed effect level (NOAEL) in all studies was 10,000mg/m(3), except for G/MTBE (<2000) and G/TBA (2000). The results provide evidence that use of the studied oxygenates are unlikely to increase the hazard of evaporative emissions during refueling, compared to those from gasoline alone.
authors.affiliation: Phillips 66 Co., 420 S. Keeler Avenue, Bartlesville, OK, United States. Electronic address: okietox@gmail.com.
authors.forename: Charles R
authors.initials: CR
authors.lastname: Clark
authors.affiliation: C&C Consulting in Toxicology, 1950 Briarcliff Ave, Meadowbrook, PA 19046, United States. Electronic address: castox@comcast.net.
authors.forename: Ceinwen A
authors.initials: CA
authors.lastname: Schreiner
authors.affiliation: Marathon Petroleum, United States. Electronic address: cmjkparker@gmail.com.
authors.forename: Craig M
authors.initials: CM
authors.lastname: Parker
authors.affiliation: American Petroleum Institute, 1220 L Street NW, Washington, DC 20005, United States. Electronic address: tmgray@reagan.com.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Gray
authors.affiliation: Huntingdon Life Sciences, Princeton Research Center, 100 Mettlers Road, East Millstone, NJ 08873, United States. Electronic address: hoffmang@princeton.huntingdon.com.
authors.forename: Gary M
authors.initials: GM
authors.lastname: Hoffman
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D005742:Gasoline / Q000633:toxicity*; D001239:Inhalation; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D018570:Risk Assessment
chemical_list: D000393:Air Pollutants; D005742:Gasoline
keywords: Diisopropyl ether; Ethanol; Ethyl t-butyl ether; Evaporative emissions; Fuel oxygenates; Gasoline vapor condensates; Methyl tertiary butyl ether; Subchronic toxicity; T-amyl methyl ether; T-butyl alcohol