Asbestosis

Asbestosis is pneumoconiosis caused by long-term inhalation of large amounts of asbestos dust, with the main pathological changes being extensive interstitial fibrosis of the lungs and pleural thickening, significantly affecting pulmonary function. It is a disease caused by long-term inhalation of asbestos dust, with pulmonary interstitial fibrosis and pleural thickening as the main pathological changes. Asbestos is a natural mineral crystal whose chemical composition is a silicate complex containing iron, magnesium, aluminum, calcium, nickel, and other elements. Asbestos fibers have properties such as resistance to acids and alkalis, heat insulation, and electrical insulation, and are widely used in industry. Workers in asbestos mining, ore dressing, and transportation, asbestos processing plant sorters and fluffers, and workers producing asbestos insulation and heat-insulating materials can all develop occupational asbestosis due to long-term inhalation of asbestos dust. The duration of employment before onset is generally about 10 years. Clinically, patients mainly present with symptoms of chronic bronchitis and emphysema, such as cough, sputum production, dyspnea, and chest distension pain. In the late stage, symptoms and signs of pulmonary dysfunction and cor pulmonale appear, and asbestos bodies can be detected in the patient's sputum. The main components of asbestos include iron, magnesium, nickel, calcium, aluminum, and other elements, and it is widely used in various industries. Occupationally exposed populations include asbestos miners, ore dressers, construction workers, insulation workers, shipyard workers, railway boiler workers, engine and maintenance workers, brake pad manufacturers and users, refractory material workers, asbestos textile workers, kiln workers, furnace builders, asbestos product demolition workers, welders, and thermal insulation material workers. The duration of employment before onset is closely related to dust concentration, type of work, and the adequacy of protective measures, generally about 10 years, but since the 1950s, the average latency period of asbestosis has shown a trend of gradual prolongation. The average duration of employment before onset of asbestosis reported in China is 22.07 years. Regarding the incidence and prevalence of asbestosis, due to inconsistent definitions and diagnostic criteria for the disease, reports from different countries are inconsistent and difficult to compare. For example, among workers exposed to asbestos in British naval dockyards with more than 25 years of employment, the detection rate of asbestos-related abnormalities on chest X-ray was 8.1%, while the cumulative prevalence of asbestosis in Chinese asbestos factories averaged 12.5%.