The effect of metal particles from a nickel refinery dump on alveolar macrophages. Part 1—Chamber exposure of Wistar rats

The effect of long-term respiratory chamber exposure to aerosol containing metal particles derived from a nickel refinery dump on the alveolar macrophage (AM) phagocytic and enzymatic activities of Wistar rats was investigated. The number of AM lavaged from the lungs of the exposed group was significantly higher than in the controls (P < 0·001). The lung lavage exhibited some pleomorphic cells. The high number (93%) of AM with phagocytised metal particles was detected. In vitro the lavaged cells showed a significant increase in ⁵¹Cr incorporation compared to the control group. A statistically significant enhancement of AM lysosomal (acid phosphatase and β-glucuronidase) enzyme activities (P < 0·05, P < 0·01) was found in the exposed animals, whereas both the plasma membrane (ATPase and 5′-nucleotidase) enzyme activities were clearly reduced (P < 0·001). Serum cytotoxicity in the exposed animals was slightly elevated.