DYNAMIC STUDY OF THE PHAGOCYTIC-ACTIVITY OF RATS LEUKOCYTES AFTER EXPOSURE TO ASBESTOS AND BASALT FIBERS

The paper presents the results of the dynamic one-year follow-up of th e phagocytic activity of Wistar-rats peripheral blood leukocytes follo wing intraperitoneal administration of asbestos and basalt fibres (Man -Made Mineral Fibres - MMMF). We investigated the phagocytic activity of leukocytes in peripheral blood following intraperitoneal administra tion of asbestos and basalt fibres to rats 2, 24, 48 h as well as 1, 2 , 4, 8 weeks and 6 and 12 months after dosing. We investigated the tim e dependent of the changes of relative granulocytes count, percentage of phagocytizing cells from leukocytes, percentage of phagocytizing gr anulocytes and percentage of phagocytizing monocytes. The results of o ur experiment showed that asbestos and basalt fibres differed in their effects on the parameters studied. Granulocyte count as well as the p hagocytic activity of leukocytes during the one-year dynamic follow-up in both dust - exposed groups of animals were found to change in two phases, characterised by the initial stimulation of the acute phase (1 ), followed by the suppression of the parameters in the chronic phase (II). Exposure to asbestos and basalt fibres led, in phase II, to impa irment of the phagocytic activity of granulocytes. Asbestos fibres at the same time significantly decreased also the phagocytic activity of monocytes. Exposure to basalt fibres did not affect the phagocytic act ivity of monocytes in phase II. It follows from the results of the exp eriment, that the monocytic component of leukocytes probably plays an important role in the development of diseases caused by exposure to fi brous dusts and basalt fibres have smaller biological effects compared with asbestos fibres.