Record Display for the EPA National Library Catalog


Main Title Mid-Frequency Hearing Loss in Rats Following Inhalation Exposure to Trichloroethylene: Evidence from Reflex Modification Audiometry.
Author Crofton, K. M. ; Zhao, X. ;
CORP Author Health Effects Research Lab., Research Triangle Park, NC. Neurotoxicology Div. ;ManTech Environmental Technology, Inc., Research Triangle Park, NC.
Publisher 1993
Year Published 1993
Report Number EPA/600/J-94/078;
Stock Number PB94-141504
Additional Subjects Hearing disorders ; Toxicity ; Trichloroethylene ; Acoustic reflex ; Graphs(Charts) ; Audiometry ; Spectrum analysis ; Sensory thresholds ; Reprints ;
Library Call Number Additional Info Location Last
NTIS  PB94-141504 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 13p
The present experiments were undertaken to characterize the hearing loss associated with 1,1,2-trichloroethylene (TCE) exposure. Adult male Long-Evans (LE) rats were exposed to TCE via inhalation (whole body) for 6 h/day for 5 days. The concentration-effect function (0-4000 ppm) was determined 3 weeks post-exposure. Animals were tested for auditory thresholds to 4, 8, 16, 24, 32, and 40-kHz tones using reflex modification audiometry. In a separate experiment, the time course of effects was determined by monitoring 16-kHz thresholds prior to, 1 h following each of the 5 exposure days, and 5 days, 1, 2, 4, 8, and 12 weeks post-exposure. At 14 weeks, these same animals were tested for thresholds to 0.5, 1, 2, 4, 8, 16, 24, 32, and 40-kHz tones. Results indicate elevated thresholds (hearing loss) for the 4000 ppm group at 8 and 16 kHz of approximately 18 and 30 dB, respectively. Time-course data demonstrated a rapid onset, a 20-dB loss at 16 kHz after the fifth exposure day, and a 40-dB loss by 2 weeks that persisted up to 14 weeks post-exposure. These data demonstrate an atypical and persistent, mid-frequency hearing loss in rats following inhalation exposure to TCE. (Copyright (c) 1993 Pergamon Press Ltd.)