Diseases silicosis

Crystalline silica, or quartz, is an abundant mineral found in sand, rock, and soil. Respirable silica dust (particles <5pm) is a known occupational hazard of the dusty trades (e.g., pottery or china manufacturing, work involving sandblasting or abrasive grinding, some construction trades). High level exposure to respirable silica can result in the chronic, progressive lung disease silicosis, characterized by inflammation and fibrosis. 

The disease is manifested by problems in breathing, at the outset only in the course of fatigue, but later on also under rest conditions. More advanced silicosis is frequently connected with bronchitis, which is manifested by coughing. Tuberculosis occurs as the most frequent complication in silicosis. Tuberculosis bacteria are able to grow and to multiply more actively in histiocytes that have phagocytized silica particles and thus, they are unable to destroy the bacteria as normal histiocytes. Thus, the combination of the two diseases (silicosis and tuberculosis) occurs frequently. 

In the preparation of powders and capsules colloidal anhydrous silica (Aerosil ) is used as lubricant. There is a water containing and an anhydrous t3q>e Aerosil. There is discussion about the possibility that Aerosil causes silicosis. The occupational disease silicosis is as a result of long-term inhalation of siliceous dust. But in [5] it is concluded ... 

Prolonged and extensive exposure to some crystalline silicates (quartz, tridymite and cristobalite) and to silicates with a fiber structure (asbestos) cause the serious diseases silicosis and asbestosis. 

Nonsilica mineral sands, such as magnetite, staurolite, and olivine, are tough (5 to 7 Mohr) and fairly dense (2.0 to 3.0 specific gravity) but are generally of finer particle size than silica sand. These heavy mineral sands — as opposed to silica sand — do not contain free silicates, the cause of the disease silicosis. In general. 

Dry abrasive blasting with silica sand is banned or restricted in many countries because of its hnk to the disease silicosis, which is caused by breathing excessive quantities of extremely fine particles of silica dust over a long period. This section discusses ... 

Miners, stonecutters, and others engaged in work where siliceous dust is breathed into large quantities often develop a serious lung disease known as silicosis. 

Inhalation of crystalline or fused vitreous silica dust, usually overlong periods, causes a disabling, progressive pulmonary disease known as silicosis (84). Amorphous siUcas have not been linked to siUcosis (85), but can cause respiratory irritation. The history and poHtics of siUcosis have been reviewed (86). Standards have been set or recommended for occupational exposures (87,88) and review articles on the health effects of siUca are available (83,89). 

Total frequencies of environmental illness are difficult to measure. When causes can be identified, however, scientists observe that frequencies of occurrence of a particular illness vary directly with the severity and extent of exposure. Particularly frequent in the workplace are skin lesions from many different causes and pulmonary diseases related to the inhalation of various dusts, such as coal dust (black lung), cotton dust (brown lung), asbestos fibers (asbestosis), and silica dust (silicosis). Environmental agents can also cause biological effects without overt clinical illness (for example, chromosome damage from irradiation). 

PNEUMOCONIOSIS A group of lung diseases of a chronic fibrotic character due to the inhalation and retention in the lungs of a variety of industrial dusts. The main diseases are asbestosis, silicosis, coalworkers pneumoconiosis and mixed-dust pneumoconiosis less common pneumoconioses are associated with talc, clay or aluminium. 

Similarly, data already available indicate that SNPs will be quite relevant in immunotoxicology and immunopharmacology. Findings that SNPs of immune-related proteins have an impact on the development of beryllium disease and silicosis suggest that SNPs may explain much of the daunting diversity of human responses to environmental and pharmaceutical agents. 

Occupational exposure to silica dust has been identified as a risk factor for several systemic autoimmune diseases. This literature dates back almost 100 years, to the description by Bramwell of diffuse scleroderma in stone masons.26 Rheumatoid arthritis and scleroderma in miners were described in the 1950s, and more formal cohort studies of miners and of granite workers were conducted in the 1980s. Other studies focusing on silicosis patients, and several case-control studies of these diseases and of Wegner... 

The disease process in workers exposed to silica fume was originally described as silicosis or acute silicosis, but it is now recognized that the X-ray pattern and symptom complex are different from both, the severity of the symptoms is less, and there is apparently no progression. It has been postulated that heavy exposure to freshly formed silica fume causes an acute reaction similar to metal fume fever. Continued or repeated exposure causes the ferroalloy disease, which has been described. This is characterized by recurrent fever over a period of 3-12 weeks, with the appearance of X-ray markings similar to silicosis. The development of classic silicosis may be the result of long, continued exposure to amorphous silica fume, or possibly concurrent exposure to crystalline silica. 

The progression of symptoms may continue after dust exposure ceases. Although there may be a factor of individual susceptibility to a given exposure to silica dust, the risk of onset and the rate of progression of the pulmonary lesion are clearly related to the character of the exposure (dust concentration and duration). The disease tends to occur after an exposure measured in years rather than in months. It is generally accepted that silicosis predisposes to active tuberculosis and that the combined disease tends to be more rapidly progressive than uncomplicated silicosis. 

He studied silicosis ( miner s disease ) and concluded that it was the result of inhaling vapors in mines, not a kind of revenge inflicted by mountain spirits. He was the first to realize that goiter could be caused by minerals in drinking water, and he prepared and used a variety of new chemical remedies for the condition. In effect, he invented chemotherapy. 

Inhalation of silica dusts or sdicate mineral dusts can cause silicosis and other lung diseases. 

Individuals whose jobs expose them to unusually high particulate concentrations are especially susceptible to health problems from the pollutant. For example, men and women who work with the mineral asbestos are very prone to development of a serious and usually fatal condition known as asbestosis, in which fibers of the mineral become embedded in the interstices (the empty spaces within tissue) of the lung. Similar conditions are observed among coal workers who inhale coal dust (pneumoconiosis, or black lung disease) textile workers (byssinosis, or brown lung disease) those who work with clay, brick, silica, glass, and other ceramic materials (silicosis) and workers exposed to high levels of beryllium fumes (berylliosis). 

Sealant Manufacturing. Most sealants use mineral-based fillers which may contain small amounts of crystalline silica. If crystalline silica is present, dust control is important to prevent inhalation of these particles. Crystalline silica is a known cause of silicosis, a debilitating disease of the lung. Another common safety concern in sealant manufacturing is the use of flammable materials. Not all sealants use flammable ingredients, but for those that do, proper inerting and grounding are needed to prevent potential explosions. 

Pneumoconiosis A chronic disease of the lungs resulting from the inhalation of various kinds of dusts. The pneumoconioses which include siderosis (iron oxide), silicosis (free silica), asbestosis (asbestos), etc., generally require a period of years for development. 

Silicosis lung disease caused from inhaling silica. 

Solid Particles. Dust and fibers from coal, clay, glass, asbestos, and minerals can lead to scarring or fibrosis of the lung lining. Pneumoconiosis, a condition common among coal miners that breathe coal dust, silicosis caused by breathing silica-containing dusts, and asbestosis from asbestos fibers are all well-known industrial pollution diseases. 

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