%0 Journal Article %A Zeen Tong %A Mark J. Utell %A Paul E. Morrow %A George M. Rusch %A M. W. Anders %T Metabolism of 1,1-Dichloro-1-fluoroethane (HCFC-141b) in Human Volunteers %D 1998 %J Drug Metabolism and Disposition %P 711-713 %V 26 %N 7 %X Human subjects were exposed by inhalation to 250, 500, and 1000 ppm 1,1-dichloro-1-fluoroethane (HCFC-141b) for 4 hr, and urine samples were collected from 0–4, 4–12, and 12–24 hr for metabolite analysis.19F nuclear magnetic resonance spectroscopic analysis of urine samples from exposed subjects showed that 2,2-dichloro-2-fluoroethyl glucuronide and dichlorofluoroacetic acid were the major and minor metabolites, respectively, of HCFC-141b. Urinary 2,2-dichloro-2-fluoroethyl glucuronide was hydrolyzed to 2,2-dichloro-2-fluoroethanol by incubation with β-glucuronidase, and the released 2,2-dichloro-2-fluoroethanol was quantified by gas chromatography/mass spectrometry. Concentrations of 2,2-dichloro-2-fluoroethanol were highest in the urine samples collected 4–12 hr after exposure, but 2,2-dichloro-2-fluoroethanol was also detected in the samples collected 0–4 and 12–24 hr after exposure. Exposure concentration–dependent excretion of 2,2-dichloro-2-fluoroethanol, obtained by hydrolysis of 2,2-dichloro-2-fluoroethyl glucuronide, was observed in seven of the eight subjects studied. In conclusion, HCFC-141b is metabolized in human subjects to 2,2-dichloro-2-fluoroethanol, which is conjugated with glucuronic acid and excreted as its glucuronide in urine in a time- and exposure concentration–dependent manner. The American Society for Pharmacology and Experimental Therapeutics %U https://dmd.aspetjournals.org/content/dmd/26/7/711.full.pdf