Occupational and environmental lung disease: mainly of the respiratory units

Pneumoconiosis

Pneumoconiosis is the non-neoplastic (i.e. excludes cancer) reaction of the lungs to inhaled mineral or organic dust and the resultant alteration in their structure. It also excludes diseases mainly of the airways like asthma, bronchitis and emphysema (although destruction of alveoli as in emphysema can be caused by dusts). Two important pneumoconioses are coal workers pneumoconiosis and silicosis.

Coalworkers' pneumoconiosis (cwp) is a pneumoconiosis caused by inhalation of coal dust and is more prevalent in underground workers exposed to higher concentrations of dust than in surface workers. The lung is destroyed by fibrosis and emphysema.

Silicosis is a pneumoconiosis caused by inhalation of quartz (or some other crystalline forms of silicon dioxide) which is lethal to macrophages that ingest it and releases their enzymes. In its early stages it is similar to cwp but the nodules in the lung tend to be denser. It is a serious and progressive disease. The term mixed dust fibrosis describes the pulmonary disorder caused by the inhalation of silica dust simultaneously with another non-fibrogenic dust. Other mineral pneumoconiosis may be caused by beryllium, talc, kaolin and mica.