Chronic inflammatory reactions in the lungs lead to circulatory problems in the microvessels, causing increased permeability of endothelial cells, edema and interstitial tissue hypoxia and respiratory tracts of lungs. Inflammation is kept by constant secretion of cytokines from specific granules of mast cells and eosinophils. Protective immune response is implemented by blast transformation of lymphocytes into plasma cells secreting antibodies. With pneumoconioses incomplete phagocytosis of foreign particles, permanent destruction of macrophages and tissue saturation with decay products stimulate an autoimmune response and the intensity of fibrosis.