Thomas M. Gray

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Vapor condensates of baseline gasoline (BGVC), or gasoline-blended 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) were evaluated for reproductive toxicity in rats at target concentrations of 2000, 10,000, or 20,000mg/m(3), 6h/day,(More)
In response to the US EPA HPV Challenge Program, this study was conducted to: (1) evaluate the relationship between PAC content and the developmental toxicity of high-boiling petroleum substances (HBPS) and (2) develop mathematical models to predict the developmental toxicity of similar untested substances based on their aromatic ring class (ARC) profiles.(More)
The repeat-dose and developmental toxicities of certain petroleum refinery streams are related to their polycyclic aromatic compound (PAC) content (Feuston et al., 1994). Building on this foundation, and working within the context of the US EPA High Production Volume (HPV) Chemical Challenge Program, we: (1) characterized relationships between PAC content(More)
In 1998, the US EPA announced the HPV Challenge Program, a voluntary chemical data collection effort. The Petroleum HPV Testing Group (PHPVTG(1)) volunteered to provide data on approximately 110 high boiling petroleum substances (HBPS), i.e. substances with final boiling points ≥ approximately 650°F (343°C). These HBPS are substances of unknown and variable(More)
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(More)
A study was undertaken within the context of the U.S. EPA HPV Chemical Challenge Program to (1) characterize relationships between PAC content and repeat-dose toxicities of high-boiling petroleum substances (HBPS) and (2) develop statistical models that could be used to predict the repeat-dose toxicity of similar untested substances. The study evaluated 47(More)
Gasoline-vapor condensate (BGVC) or condensed vapors from gasoline blended with methyl t-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) were evaluated for developmental toxicity in Sprague-Dawley rats exposed via inhalation on gestation days (GD) 5-20(More)
CD-1 mice were exposed to baseline gasoline vapor condensate (BGVC) alone or to vapors of gasoline blended with methyl tertiary butyl ether (G/MTBE). Inhalation exposures were 6h/d on GD 5-17 at levels of 0, 2000, 10,000, and 20,000mg/m(3). Dams were evaluated for evidence of maternal toxicity, and fetuses were weighed, sexed, and evaluated for external,(More)
The oral absorption of flurbiprofen, an antiinflammatory nonsteroidal compound, was compared in the fasted vs the fed state. When ingested as an aqueous solution of the sodium salt, absorption kinetics followed a monoexponential pattern in half of the subjects and a bimodal pattern with a lag time before the onset of the second phase of absorption in the(More)
There are several specific types of high-boiling petroleum substances (HBPS) having final boiling points >343°C), in which genetic toxicity can be related to the content of polycyclic aromatic compounds (PACs), specifically crude oils, gas oils, heavy fuel oils, lubricant base oils, waxes and aromatic extracts. Evaluation of optimized Salmonella tests(More)