Occupational Lung Diseases or pneumoconiosis ( pneumo = LUNGS; conis = DUST in Greek) is a term used for lung Diseases caused by inhalation of ducts, mostly at work, these diseases are called dust diseases.

History

• Ancient Times

  Pliny the Elder (AD 23-79) recorded the danger to miners from inhalation of fumes and vapours Because mining was so dangerous, it was considered suitable only for slaves and as punishment for criminals.

• The Middle Ages

  The Erz Mountains in Bohemia were an important area for the mining and refining useful and precious metals. A physician named Agricola became the town physician of Joachimsthal.
  He recognized that mining activities could lead to conditions that caused chronic shortness of the breath.

• Ramazzini (1633-1714)

  He published De Morbis Artificum Diatriba in 1700 (Treatise on the Diseases of Workers). He describes:

  1. Dyspnea and metal poisoning in miners
  2. Bronchitis from irritant fumes
  3. Lung fibrosis in potters
  4. Asthma from exposure to corn &flour
  5. Silicosis in stonemasons

• The Industrial Revolution

  Production of steel on an industrial scale.Increased coal mining to make coke Fabrics are made in factories from cotton and wool thanks to new machinery. Charles Turner Thackrah, a town doctor, reported his observations on lung disease in miners and metal grinders and described a new method of measuring the lung volume. In 1897, injured workers had rights to compensation from contributions paid by employers. Silicosis (1919) and Asbestosis (1931) were later recognized and covered.

• The Modern Era

  E.R.A. Merewether (1892-1970) established danger of asbestos and promoted first legislation to control it. Late 19th century, occupational lung cancers are described in miners. Allergic alveolitis is described in 1932 Berylliosis is described in Germany in 1933- 1970, Congress passes OSHA legislation.

• Principles of Occupational Lung Disease

  Industrial processes change and become increasingly complex. We should anticipate a broader range of potentially toxic substances in the air.
  It is unlikely that lung will develop many new ways to react to inhaled substances. We’ll see old lung diseases with new causes

  Toxic reactions can occur on the first exposure. Immunologically-mediated diseases require re-exposure . Irritants are noticed quickly by patients and create symptoms proximally to distally. (chlorine and ammonia) .Toxins attack the alveolar membrane (phosgene and nitrogen dioxide). Symptoms usually begin several weeks after exposure begins. Early in syndrome, the patient may just notice a dry cough. The patient may not be continuously exposed to provoking antigens. A portable peak-flow meter and a diary is very helpful in determining if a workplace antigen is responsible.

  co- worker Pneumoconiosis

  The term is currently defined by International Labour Organisation (ILO) as the accumulation of dust in lungs and the tissue reactions to its presence; tissue reaction may be non-collagenous (minimal stromal reaction) or collagenous (when scarring is permanent.

  1. Asbestosis: A very fibro genic dust, that causes pulmonary fibrosis,
     pleural plaques, benign pleural effusions
     Mesothelioma, carcinoma of the lung
  2. Silicosis:
     1. Simple Silicosis: small nodules, predominately upper lobes; patient often asymptomatic
     2. Complicated Silicosis (Progressive Massive Fibrosis): coalescence into large nodules or masses with retraction of upper lobes
     3. Tuberculosis is a common complication
  3. Berylliosis: Berylliosis is caused by heavy exposure to dust or fumes of metallic beryllium or its sates. Beryllium was used in the past in fluorescent tubes and light bulbs but currently, it is principally used in nuclear and aerospace industries and in the manufacture of electrical equipment
     1. Acute Berylliosis
        • Occurs to individual who unusually sensitive to it
        • for 2-3 week
  4. chronic Berylliosis
     • occurs in individuals who are sensitized to it for a number of years
     • Often delay of 20 or more year