Comparative Inhalation Toxicology of Selected Materials. Phase 3 Studies
Abstract
A subchronic inhalation study of powdered Cu-Zn alloy (Cu-Zn) was conducted with F344/N rats. Exposures were 1.5 hours/day, 4 days/week to 0, 0. 32, 1.0, 3.2, or 10 mg Cu-Zn/m3 for 13 weeks, followed by a 4-Week recovery period. Rats were exposed nose-only to aerosols with average mass median aerodynamic diameters of 1.1 um (geometric standard deviation 2.7). The Cu-Zu alloy did not accumulate in lungs, indicating that it cleared rapidly and reached equilibrium concentrations in tissues of the respiratory tract after a few days of exposure. Exposures to 3.2 or 10 mg Cu-Zn/m3, 1.5 hours/day, 4 days/ week for 13 weeks produced significant lesions and functional changes in the respiratory tracts of F344/N rats. The only lesion produced by exposure to 1.0 mg Cu-Zn/m3 was a mild focal atrophy of olfactory epithelium in 14 percent of the rats; this lesion resolved within 4 weeks after exposure to Cu-Zn ended. No effects were detected after exposure to 0.32 mg Cu-Zn/m3. Considering the cumulative results of this study, the no observable adverse effects level (NOAEL) for exposures of F344/N rats is defined as exposures equivalent to inhalation of 0.32 mg Cu-Zn/m3, 1.5 hours/day, 4 days/week. Keywords: Rats; Inhalation; Subchronic exposure; Copper; Zinc; Alloy; Toxicity; Exposure physiology; Toxicity.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1988
- Accession Number
- ADA206484
Entities
People
- A. F. Eidson
- D. E. Bice
- D. G. Burt
- E. G. Damon
- F. A. Seiler
- F. F. Hahn
- H. C. Yeh
- J. A. Pickrell
- J. L. Mauderly
- J. R. Harkema
- M. B. Snipes
- R. F. Henderson
Organizations
- Lovelace Foundation