Health assessment of gasoline and fuel oxygenate vapors: micronucleus and sister chromatid exchange evaluations.
Micronucleus and sister chromatid exchange (SCE) tests were performed for vapor condensate of baseline gasoline (BGVC), or gasoline with oxygenates, methyl tert-butyl ether (G/MTBE), ethyl tert butyl ether (G/ETBE), t-amyl methyl ether (G/TAME), diisopropyl ether (G/DIPE), t-butyl alcohol (TBA), or ethanol (G/EtOH). Sprague Dawley rats (the same 5/sex/group for both endpoints) were exposed to 0, 2000, 10,000, or 20,000mg/m(3) of each condensate, 6h/day, 5days/week over 4weeks. Positive controls (5/sex/test) were given cyclophosphamide IP, 24h prior to sacrifice at 5mg/kg (SCE test) and 40mg/kg (micronucleus test). Blood was collected from the abdominal aorta for the SCE test and femurs removed for the micronucleus test. Blood cell cultures were treated with 5μg/ml bromodeoxyuridine (BrdU) for SCE evaluation. No significant increases in micronucleated immature erythrocytes were observed for any test material. Statistically significant increases in SCE were observed in rats given BGVC alone or in female rats given G/MTBE. G/TAME induced increased SCE in both sexes at the highest dose only. Although DNA perturbation was observed for several samples, DNA damage was not expressed as increased micronuclei in bone marrow cells. Inclusion of oxygenates in gasoline did not increase the effects of gasoline alone or produce a cytogenetic hazard.
C&C Consulting in Toxicology, 1950 Briarcliff Ave, Meadowbrook, PA 19046, United States. Electronic address: castox@comcast.net.
Ceinwen A
CA
Schreiner
Huntingdon Life Sciences Inc, 100 Mettlers Road, East Millstone, NJ 08875, United States. Electronic address: hoffmang@princeton.huntingdon.com.
Gary M
GM
Hoffman
U.S. Food and Drug Administration (FDA), Center for Drug Evaluation and Research, 10903 New Hampshire Ave, Silver Spring, MD 20993, United States. Electronic address: ramadevi.gudi@fda.hhs.gov.
Ramadevi
R
Gudi
Phillips 66 Co (retired), 420 S. Keeler Ave, Bartlesville, OK 74004, United States. Electronic address: okietox@gmail.com.
Charles R
CR
Clark
D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D005260:Female; D005742:Gasoline / Q000633:toxicity*; D015162:Micronucleus Tests; D051381:Rats; D017207:Rats, Sprague-Dawley; D018570:Risk Assessment; D012854:Sister Chromatid Exchange / Q000187:drug effects*
D000393:Air Pollutants; D005742:Gasoline
Bromodeoxyuridine (BrdU); Diisopropyl ether (DIPE); Ethanol (EtOH); Ethyl tert butyl ether (ETBE); Methyl tert-butyl ether (MTBE); Micronucleated immature erythrocytes (MIE); Micronucleus; Sister chromatid exchange (SCE); t-Amyl methyl ether (TAME); t-Butyl alcohol (TBA)