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世界上生产的石棉大约有2/3用于水泥石棉工业,以15～20%石棉和硅酸盐水泥(主要由硅酸钙、铝酸三钙和铁酸三钙组成,亦含1～5%游离二氧化硅及少量钙、铝,铁和镁的氧化物)相混合而成水泥石棉。接触水泥石棉粉尘的工人所得的混合尘肺在中下肺野的纤维化病变主要由石棉尘所致,圆形病灶与肺门病变为二氧化硅作用。水泥石棉尘肺发病率在不同国家接触工人中差异很大,印度达27%,埃及接触水泥石棉20年以上的工人发病率为81%,而西德仅为0.5%
Approximately two-thirds of the asbestos produced in the world is used in the cement asbestos industry, consisting of 15-20% asbestos and Portland cement (mainly composed of calcium silicate, tricalcium aluminate and ferrite, also containing 1-5 % Free silica and a small amount of calcium, aluminum, iron and magnesium oxide) into a mixture of asbestos. The mixed pneumoconiosis obtained by workers exposed to cement asbestos dust is mainly caused by asbestos dust in the fibrosis of the middle and lower lung fields, and the circular lesions and hilar lesions are caused by silica. The incidence of cement asbestos pneumoconiosis varies widely among workers exposed to different countries, with 27% in India, 81% in Egypt exposed to cement asbestos over 20 years, and only 0.5% in West Germany