title: Health assessment of gasoline and fuel oxygenate vapors: immunotoxicity evaluation.
abstract: Female Sprague Dawley rats were exposed via inhalation to vapor condensates of either gasoline or gasoline combined with various fuel oxygenates to assess potential immunotoxicity of evaporative emissions. Test articles included vapor condensates prepared from "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/mg(3) administered for 6h/day, 5days/week for 4weeks. The antibody-forming cell (AFC) response to the T-dependent antigen, sheep erythrocyte (sRBC), was used to determine the effects of the gasoline vapor condensates on the humoral components of the immune system. Exposure to BGVC, G/MTBE, G/TAME, and G/TBA did not result in significant changes in the IgM AFC response to sRBC, when evaluated as either specific activity (AFC/10(6) spleen cells) or as total spleen activity (AFC/spleen). Exposure to G/EtOH and G/DIPE resulted in a dose-dependent decrease in the AFC response, reaching the level of statistical significance only at the high 20,000mg/m(3) level. Exposure to G/ETBE resulted in a statistically significant decrease in the AFC response at the middle (10,000mg/m(3)) and high (20,000mg/m(3)) exposure concentrations.
authors.affiliation: ImmunoTox®, Inc., 800 East Leigh Street, Richmond, VA 23298, United States. Electronic address: kwhite@immunotox.com.
authors.forename: Kimber L
authors.initials: KL
authors.lastname: White
authors.affiliation: ImmunoTox®, Inc., 800 East Leigh Street, Richmond, VA 23298, United States. Electronic address: vpeachee@immunotox.com.
authors.forename: Vanessa L
authors.initials: VL
authors.lastname: Peachee
authors.affiliation: Cambridge Environmental, Inc., United States. Electronic address: SarahAMarshall99@comcast.net.
authors.forename: Sarah R
authors.initials: SR
authors.lastname: Armstrong
authors.affiliation: Twerdok Consulting, LLC, 1613 Featherwood Street, Silver Spring, MD 20904, United States. Electronic address: letwerdok@verizon.net.
authors.forename: Lorraine E
authors.initials: LE
authors.lastname: Twerdok
authors.affiliation: Phillips 66 Co., 420 S. Keeler Ave, Bartlesville, OK 74006, 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
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D000921:Antibody-Producing Cells / Q000187:drug effects* / Q000276:immunology; D005260:Female; D005742:Gasoline / Q000633:toxicity*; D007075:Immunoglobulin M / Q000276:immunology; D001239:Inhalation; D051381:Rats; D017207:Rats, Sprague-Dawley; D018570:Risk Assessment
chemical_list: D000393:Air Pollutants; D005742:Gasoline; D007075:Immunoglobulin M
keywords: Diisopropyl ether; Ethanol; Ethyl t-butyl ether; Evaporative emissions; Gasoline vapor condensates; Immunotoxicity; Methyl tertiary butyl ether; Plaque assay; t-Amyl methyl ether; t-Butyl alcohol