HOME

TheInfoList



OR:

Pneumoconiosis is the general term for a class of interstitial lung disease where inhalation of
dust Dust is made of fine particles of solid matter. On Earth, it generally consists of particles in the atmosphere that come from various sources such as soil lifted by wind (an aeolian process), volcanic eruptions, and pollution. Dust in ...
( for example, ash dust, lead particles, pollen grains etc) has caused interstitial fibrosis. The three most common types are asbestosis, silicosis, and coal miner's lung. Pneumoconiosis often causes restrictive impairment, although diagnosable pneumoconiosis can occur without measurable impairment of lung function. Depending on extent and severity, it may cause death within months or years, or it may never produce symptoms. It is usually an occupational lung disease, typically from years of dust exposure during work in mining; textile milling; shipbuilding, ship repairing, and/or shipbreaking; sandblasting; industrial tasks; rock drilling (subways or building pilings); or agriculture. It is one of the most common occupational diseases in the world.


Types

Depending upon the type of dust, the disease is given different names: * Coalworker's pneumoconiosis (also known as coal miner's lung, black lung or anthracosis) –
coal Coal is a combustible black or brownish-black sedimentary rock, formed as stratum, rock strata called coal seams. Coal is mostly carbon with variable amounts of other Chemical element, elements, chiefly hydrogen, sulfur, oxygen, and nitrogen ...
,
carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes ...
* Aluminosis
Aluminium Aluminium (aluminum in AmE, American and CanE, Canadian English) is a chemical element with the Symbol (chemistry), symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately o ...
*
Asbestosis Asbestosis is long-term inflammation and scarring of the lungs due to asbestos fibers. Symptoms may include shortness of breath, cough, wheezing, and chest tightness. Complications may include lung cancer, mesothelioma, and pulmonary heart diseas ...
asbestos * Silicosis (also known as "grinder's disease" or Potter's rot) – crystalline silica dust * Bauxite fibrosis
bauxite Bauxite is a sedimentary rock with a relatively high aluminium content. It is the world's main source of aluminium and gallium. Bauxite consists mostly of the aluminium minerals gibbsite (Al(OH)3), boehmite (γ-AlO(OH)) and diaspore (α-AlO(O ...
* Berylliosisberyllium * Siderosis
iron Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in ...
* Byssinosis – Byssinosis is caused by
cotton Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus '' Gossypium'' in the mallow family Malvaceae. The fiber is almost pure cellulose, and can contain minor p ...
dust inhalation and typically demonstrates a different pattern of lung abnormalities than most other pneumoconiosis. * Chalicosis – fine dust from stonecutting * Silicosiderosis (also sometimes called iron miner's lung) – mixed dust containing silica and iron * Labrador lung (found in miners in Labrador,
Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tota ...
) – mixed dust containing iron, silica and anthophyllite, a type of asbestos *
Stannosis Stannosis is an occupational, non-fibrotic pneumoconiosis caused by chronic exposure and inhalation of tin. Pneumoconiosis is essentially when inorganic dust is found on the lung tissue; in this case, caused by tin oxide minerals. Dust particles a ...
– tin oxide * Talcosistalc * Baritosis - a benign type of pneumoconiosis caused by barium inhalation; it typically causes little or no overgrowth, hardening, and/or fibrosis. * Mixed-dust pneumoconiosis


Pathogenesis

The reaction of the lung to mineral dusts depends on many variables, including size, shape, solubility, and reactivity of the particles. For example, particles greater than 5 to 10 μm are unlikely to reach distal airways, whereas particles smaller than 0.5 μm move into and out of alveoli, often without substantial deposition and injury. Particles that are 1 to 5 μm in diameter are the most dangerous, because they get lodged at the bifurcation of the distal airways. Coal dust is relatively inert, and large amounts must be deposited in the lungs before lung disease is clinically detectable. Silica, asbestos, and beryllium are more reactive than coal dust, resulting in fibrotic reactions at lower concentrations. Most inhaled dust is entrapped in the mucus blanket and rapidly removed from the lung by ciliary movement. However, some of the particles become impacted at alveolar duct bifurcations, where macrophages accumulate and engulf the trapped particulates. The pulmonary alveolar macrophage is a key cellular element in the initiation and perpetuation of lung injury and fibrosis. Many particles activate the inflammasome and induce IL-1 production. The more reactive particles trigger the macrophages to release a number of products that mediate an inflammatory response and initiate
fibroblast A fibroblast is a type of biological cell that synthesizes the extracellular matrix and collagen, produces the structural framework ( stroma) for animal tissues, and plays a critical role in wound healing. Fibroblasts are the most common cells of ...
proliferation and collagen deposition. Some of the inhaled particles may reach the lymphatics either by direct drainage or within migrating macrophages and thereby initiate an immune response to components of the particulates and/or to self-proteins that are modified by the particles. This then leads to an amplification and extension of the local reaction. Tobacco smoking worsens the effects of all inhaled mineral dusts, more so with asbestos than with any other particle.


Diagnosis

Typical indications on patient assessment include: * Cough * Shortness of breath * Chest tightness * Chest X-ray may show a characteristic patchy, subpleural, bibasilar interstitial infiltrates or small cystic radiolucencies called honeycombing, particularly in advanced disease. Pneumoconiosis in combination with multiple pulmonary
rheumatoid nodules A rheumatoid nodule is a lump of tissue, or an area of swelling, that appear on the exterior of the skin usually around the olecranon (tip of the elbow) or the interphalangeal joints (finger knuckles), but can appear in other areas. There are fou ...
in
rheumatoid arthritis Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects synovial joint, joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and ...
patients is known as Caplan's syndrome.


Epidemiology

The prevalence as of 2021 of pneumoconiosis is around 527,500 cases, with over 60,000 new patients reported globally in 2017. Prevalence has trended somewhat downward since 2015. The mortality of pneumoconiosis patients remained at a high level in recent years, with over 21,000 deaths each year since 2015. It is likely that pneumoconiosis is under-diagnosed and under-reported, especially in countries without highly developed healthcare systems.


Treatment and Prognosis

Lung damage due to pneumoconiosis cannot be reversed. However, some steps can slow down disease progression and relieve symptoms. These include the prescription of medications and breathing treatments to open airways and reduce inflammation. Pulmonary rehabilitation and supplemental oxygen may also be recommended. A lung transplant may be needed in cases of serious diseases. If the patient smokes, smoking cessation is also important. Regular testing, such as X-rays or lung function tests, may be indicated to monitor disease progression.


Prevention

To reduce the likelihood of developing pneumoconiosis, individuals working in affected industries should wear a mask, wash skin that comes in contact with dust, remove dust from clothing and wash the face and hands before eating or drinking. In addition, governments often regulate industry, especially mines, to limit how much dust is in the air. In the United States, coal miners injured by pneumoconiosis and their families may receive monthly payments and medical benefits under the Black Lung Benefits Act.


See also

* Aluminosis * Black Lung Benefits Act of 1972 * Chalicosis * Philip D'Arcy Hart * Pneumonoultramicroscopicsilicovolcanoconiosis * Popcorn workers' lung diseasediacetyl emissions and airborne dust from butter flavorings used in microwave popcorn production


References


Further reading

* (Paperback ed. (2009) Cardiff University .


External links

* * *
Black Lung — United Mine Workers of America
*
A Conversation about Mining and Black Lung Disease

Flavorings-Related Lung Disease

The Institute of Occupational Medicine and its research into pneumocomiosis
* {{Authority control Mine safety Coal Occupational diseases Lung diseases due to external agents