Comparison of the pulmonary responses to chrysotile and amosite asbestos administered intratracheally. I) Early phase of cellular reactions.

To clarify whether serpentine and amphibole asbestos have different effects on the lung, UICC chrysotile and amosite asbestos were injected intratracheally into hamster lung, and the lungs were examined at 30 min, 1, 4, 8, and 24 h, and 2 and 4 days after asbestos application by light and scanning electron microscopy. A leukocyte and macrophage reaction appeared at 4 h and increased up to 2 days, and the cell reaction was stronger and more prolonged after application of chrysotile than after application of amosite asbestos. Furthermore, chrysotile induced more prominent cell (leukocytes or/and macrophages) necrosis and alveolar wall thickening. These findings indicate that chrysotile asbestos induces more stronger cell reactions in the alveolar wall, and is more noxious than amosite.