Workers with silicosis are furthermore prone to develop other lung diseases due to the fibrotic
effect crystalline silica have on lung tissue. Other lung diseases associated with crystalline silica
exposure are increased mycobacterium infections i.e., tuberculosis, brochogenic carcinoma and
immune-mediated diseases i.e., scleroderma. A lifetime exposure to 0.1 mg.m3 increase the
likelihood to develop lung cancer by 30%. Recently there are indications that nephrotoxicity in
workers who are exposed to silica is linked with quartz exposure. There exist numerous case
reports linking acute glomerulonephritis with accelerated silicosis Ref.(11). Hotz et al. Ref.(16)
mentioned that sub clinical effects on kidney function may occur in workers who are exposed to
silica for short periods. Out of all diseases mentioned only silicosis, tuberculosis and
bronchogenic carcinoma are compensatable diseases.
A primary feature that develops in lungs of silica quartz exposed workers is nodule formation in
the upper zones of the lung Ref.(17). Nodule formation is usually the result of many years of
exposure to relatively low levels of dust that contain silica quartz Ref.(