| Abstrakt: |
Comparative Inhalation Toxicity of Nickel Sulfate to F344/N Rats and B6C3F Mice Exposed for Twelve Days. BENSON, J. M., BURT, D. G., CARPENTER, R. L., EIDSON, A. F., HAHN, F. F., HALEY, P. J., HANSON, R. L., HOBBS, C. H., PICKRELL, J. A., AND DUNNICK, J. K. (1988). 10, 164-178. Groups of F344/N rats and B6C3F, mice were exposed to aerosols of nickel sulfate hexahydrate (NiSO-6HO) 6 hr/day for 12 days to determine the short-term inhalation toxicity of this compound. Target exposure concentrations were 60, 30, 15, 7, 3.5, and 0 mg NiSO.6HO/m. Endpoints evaluated included clinical signs, mortality, quantities of Ni in selected tissues, effect on mouse resistance to tumor cells, and pathological changes in tissues of both rats and mice. All mice exposed to 7 mg NiSO 6H2O/m or greater and 10 rats exposed to 15 mg NiSO 6H2O/m or greater died before the termination of exposures. Quantities of Ni remaining in lungs of rats at the end of the exposure were independent of exposure concentration. Lung burdens of Ni in mice were approximately one-half that in lungs of rats. Exposure of female mice to 3.5 mg NiSO 6H2O/mhad no effect on resistance to tumor cells as determined by spleen natural killer cell activity. Histopathological changes were seen in tissues of rats and mice exposed to as low as 3.5 mg NiSO 6H2O/m. Lesions related to NiSO 6H2O/mexposure occurred in lung, nose, and bronchial and mediastinal lymph nodes. Results indicated that exposure of rats and mice to amounts of NiSO 6H2O/maerosols resulting in Ni exposure concentrations only eight times greater than the current threshold limit value for soluble Ni (0.1 mg/m) for as little as 12 days can cause significant lesions of the. [ABSTRACT FROM PUBLISHER] |
