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Immunotoxicity

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Limited information characterizing specific investigations associated with exposure to nickel oxide in laboratory animals were identified.

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Additional information

Limited information characterizing specific investigations associated with exposure to nickel oxide in laboratory animals were identified. Data were limited to two studies assessing immunotoxicity; no studies evaluating neurotoxicity or other investigations were identified. The two immunotoxicity studies both evaluated effects following inhalation of nickel oxide, one in rats and one in mice. Spiegelberg et al. (1984) examined the effects of NiO (unspecificed color) inhalation on alveolar macrophages and the humoral immune systems in Wistar rats following 4 weeks or 4 months of exposure. Based on effects of the size, number, and phagocytic activity of alveolar macrophages in lung lavage samples, or altered antibody titers to sheep red blood cells (e.g., assessment of humoral immunity), the authors concluded that animals may become more prone to infections caused by bacteria or viruses following inhalation of NiO. They further commented that alveolar macrophages and the humoral immune system are potentially sensitive markers of detecting effects of NiO inhalation. Haley et al (1990) reported that inhalation of nickel compounds at occupationally relevant concentrations can result in significant alterations of pulmonary and systemic immune defenses in mice. These findings were based on effects to thymic weights, number of lung-associated lymph nodes, the number of nucleated cells, antibody-forming cells, and spleen cells, as well as phagocytic activity following 65 days of exposure. Collectively, these studies suggest that inhalation to NiO has potential to adversely impact systemic immune function in laboratory species.

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