Accession Number : ADA299025

Title :   Metabolism of 2,2-Dichloro-1,1,1 Trifluoroethane (HCFC-123) by Human Hepatic Microsomes.

Descriptive Note : Final rept. Aug 92-Apr 93,

Corporate Author : MANTECH ENVIRONMENTAL TECHNOLOGY INC DAYTON OH

Personal Author(s) : Godlin, C. S. ; Ketcha, M. M. ; Drerup, J. M. ; Vinegar, A.

PDF Url : ADA299025

Report Date : NOV 1994

Pagination or Media Count : 17

Abstract : As part of its safety evaluation, the in vitro metabolism of 2,2-dichloro-1,1,l-trifluoroethane (HCFC-123), a replacement candidate for Halon 1211, by human hepatic microsomes, was assessed. Microsomal incubations containing HCFC-123 ranging from 6 to 75% (v/v) in the headspace produced increasing amounts of trifluoroacetic acid (IFA); the kinetics suggested substrate- saturation although substrate inhibition was apparent above a concentration of 36%. The rate of ThA formation with respect to pH, time, and protein concentration permitted linear rates of formation to be determined. Rates of ThA formation from incubations conducted at physiological pH, and containing concentrations of HCFC-123 in solution representing estimated concentrations of the chemical in human liver at steady-state, were 67% of those obtained under optimal conditions.

Descriptors :   *METABOLISM, *MICROSOMES, TEST AND EVALUATION, STEADY STATE, OPTIMIZATION, HUMANS, SUBSTRATES, IN VITRO ANALYSIS, SAFETY, INCUBATION, PHYSIOLOGY, LIVER, INHIBITION, PH FACTOR.

Subject Categories : Anatomy and Physiology
      Biochemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE