生产性粉尘是尘肺发生的物质基础,其致病作用一方面取决于粉尘的性质,另一方面取决于呼吸系统的防御功能及粉尘沉着的部位。鼻、咽、气管和支气管能阻留吸入粉尘总量的95％以上,绝大部分比较粗大的尘粒(直径大于10微米)被阻留在上呼吸道内,通过纤毛运动,咳嗽反射随痰排出体外或被咽下。少量进入呼吸性细支气 Productive dust is the material basis for the occurrence of pneumoconiosis. Its pathogenic role depends on the one hand on the nature of the dust and on the other hand on the respiratory defenses and dusty areas. Nasal, pharynx, trachea and bronchi can hold more than 95% of inhaled dust, the vast majority of the larger dust particles (diameter greater than 10 microns) were blocked in the upper respiratory tract, through the ciliary movement, cough reflex with the sputum In vitro or ingested. A small amount of access to respiratory bronchioles