Asbestosis
• Asbestos consists of certain types of fibrous material made up of silicates
• Silica may be combined with:
– Magnesium
– Iron
– Calcium
– Aluminum
• Asbestos is of two types:
1. Serpentine or Chrysolite –
– Hydrated magnesium
– 90% of world’s asbestos production
2. Amphibole
– Contains little magnesium
– Fibers are straight and longer than chrysotile fibers
• Asbestos is used in the manufacture of:
– Asbestos cement
– Fire proof textiles
– Roof tiling
– Brake lining
– Gaskets etc.
• Asbestos enters the body by inhalation and fine dust may be deposited in the alveoli
• The fibers are insoluble
• The dust deposited in the lungs causes pulmonary fibrosis leading to:
– Respiratory insufficiency and death
– Carcinoma of bronchus
– Mesothelioma of the pleura or peritoneum (otherwise a rare form of cancer) and
– Cancer of the gastro intestinal tract
• The risk of bronchial cancer is reported to be high if occupational exposure is combined with cigarette smoking
• The fibrosis is
– Due to mechanical irritation
– Is peri-bronchial,
– Diffuse in character and
• Basal in location - This is in contrast to silicosis
References
• Chapter 1 - Dust: Definitions and Concepts; Hazard Prevention and Control in the Work Environment: Airborne Dust WHO/SDE/OEH/99.14 available at: http://www.who.int/occupational_health/publications/en/oehairbornedust3.pdf, accessed on 16th Feb 2017
• Park’s Textbook of Preventive and Social Medicine
Types of Pneumoconiosis: http://www.ihatepsm.com/blog/pneumoconioses
Silicosis: http://www.ihatepsm.com/blog/silicosis
Anthracosis: http://www.ihatepsm.com/blog/anthracosis
Byssinosis: http://www.ihatepsm.com/blog/byssinosis
Bagassosis: http://www.ihatepsm.com/blog/bagassosis
Asbestosis: http://www.ihatepsm.com/blog/asbestosis
Farmer’s Lung: http://www.ihatepsm.com/blog/farmer%E2%80%99s-lung
Lecture on Pneumoconiosis: http://www.ihatepsm.com/category/occupational-health