Disposition, metabolism, and toxicity of methyl tertiary butyl ether, an oxygenate for reformulated gasoline.
Studies of the toxicology of methyl tertiary butyl ether (MTBE) were reviewed as a possible information base for evaluating the health effects of evaporative emissions from reformulated gasoline (RFG).
The major metabolites of the oxidative demethylation of MTBE in vivo were methanol and tertiary butyl alcohol (TBA), whereas formaldehyde and TBA were the principal products of hepatic microsomal oxidation by cytochrome P-450.
Pharmacokinetic studies in rats treated with intragastric MTBE in corn oil gave an initial disposition T1/2 for MTBE of 0.32 h. The decline in the serum drug versus time curve for MTBE in rats was accompanied by a progressive increase in serum methanol concentrations to levels more than 50-200 times those of the parent compound.
Repeated exposure of MTBE vapor by inhalation in rats resulted in dose-dependent increases in MTBE in the blood, brain, and adipose tissue compartments.
Blood concentrations of TBA were also dose dependent and provided an estimate of the total amount of MTBE distributed to peripheral drug metabolizing compartments.
Perirenal fat/blood MTBE concentration ratios ranged from 9.7 to 11.6 after 15 wk of intermittent exposure.
During an oxyfuels program in Fairbanks, AK, blood levels of occupationally exposed workers were 0.2-31.5 mug/L MTBE and 1.6 to 72.2 mug/L TBA with a mean TBA : MTBE blood concentration ratio of 4.2. In patients who received MTBE by percutaneous, transhepatic puncture for the dissolution of cho...
Mots-clés Pascal : Additif, Essence, Métabolisme, Toxicocinétique, Cinétique, Toxicité, Rat, Rodentia, Mammalia, Vertebrata, Animal, Voie intragastrique, Homme, Volontaire, Exposition professionnelle, Médecine travail, Lithiase, Vésicule biliaire, Ether(t-butyl méthyl)
Mots-clés Pascal anglais : Additive, Gasoline, Metabolism, Toxicokinetics, Kinetics, Toxicity, Rat, Rodentia, Mammalia, Vertebrata, Animal, Intragastric administration, Human, Volunteer, Occupational exposure, Occupational medicine, Lithiasis, Gallbladder
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Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 96-0231266
Code Inist : 002B03L06. Création : 199608.