@article {Tong711, author = {Zeen Tong and Mark J. Utell and Paul E. Morrow and George M. Rusch and M. W. Anders}, title = {Metabolism of 1,1-Dichloro-1-fluoroethane (HCFC-141b) in Human Volunteers}, volume = {26}, number = {7}, pages = {711--713}, year = {1998}, publisher = {American Society for Pharmacology and Experimental Therapeutics}, abstract = {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{\textendash}4, 4{\textendash}12, and 12{\textendash}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{\textendash}12 hr after exposure, but 2,2-dichloro-2-fluoroethanol was also detected in the samples collected 0{\textendash}4 and 12{\textendash}24 hr after exposure. Exposure concentration{\textendash}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{\textendash}dependent manner. The American Society for Pharmacology and Experimental Therapeutics}, issn = {0090-9556}, URL = {https://dmd.aspetjournals.org/content/26/7/711}, eprint = {https://dmd.aspetjournals.org/content/26/7/711.full.pdf}, journal = {Drug Metabolism and Disposition} }