Silicosis acute

Silica is the main component of most rocks and is a crystalline substance made of silicon and oxygen. It occurs in quartz (found in granite), sand and flint, which are present in a wide variety of construction materials. Harm is caused by the inhalation of silica dust which can lead to silicosis (acute and chronic), fibrosis and pneumoconiosis. Activities which can expose workers and members of the public to silica dust include ... 

NIOSH REL is 6 mg/m and OSHA PEL 80 mg/m for diatomaceous earth. Inhalation of crystalline silica causes dryness and irritation to the respiratory system. Symptoms may include coughing, sore throat, breathing difficulty (dyspnea), and wheezing. Excessive inhalation may cause decreased pulmonary function, limg damage and silicosis. Acute silicosis is manifested by dyspnea, fever, cough, and weight loss. Severe respiratory symptoms may lead to death. 

Absher M, Sjostrand M, Baldor LC, Hemenway DR, Kelley J. Patterns of secretion of transforming growth factor-alpha (TGF-alpha) in experimental silicosis. Acute and subacute effects of cristobalite exposure in the rat. Reg Immunol 1993 5 225-231. 

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. 

By subcutaneous or intravenous injection of an aqueous solution of (PVNO) (20) or by inhalation of an aerosol of a PVNO-sohition (21) the cytotoxieal action of quartz dust can be prevented prophylactically and acute or chronic silicosis can be... 

Chronic bronchitis, pneumoconiosis, obstructive lung disease, focal emphysema, progressive massive fibrosis (PMF), coal workers pneumoconiosis (CWP), siUcosis Acute bronchospasm, pneumonitis, chronic exposure leads to Itmg fibrosis, progressive massive fibrosis (PMF), coal workers pneumoconiosis (CWP), silicosis Ocular and upper airway irritation, bronchospasm in severe exposure, contact dermatitis... 

Silicon toxicity is virtually limited to occupational exposure to silicon compounds e.g. miners, sandblasters, bricklayers, pottery workers in which inhalation of the compounds has been associated with the diseases of the lung. The later being evidenced by nodule formation and acute silicosis, mixed dust fibrosis and diatomite pneumoconiosis. 

ACUTE HEALTH RISKS exposure to very high levels of Silica, Cristobalite can cause a serious lung disease called Silicosis Simple Silicosis may only cause changes in chest x-ray... 

Chronic exposure to crystalline silica particulates may cause silicosis, which is a chronic lung disease with symptoms of scattered rounded nodules of scar tissue in the lungs. Very heavy exposures to quartz dusts of very small particle size can cause acute silicosis. This disease is rapidly progressive aud can develop within a few months of initial exposure. It is often associated with mbercu-losis. Death can occur within 1 or 2 years. 

Chronic fibrotic occupational lung diseases include asbestosis (see p 121), silicosis, coal workers pneumoconiosis, and a few other less common fibrotic lung diseases associated with occupational exposures to such substances as beryllium and hard metal (cobalt-tungsten carbide). These conditions occur after years of exposure and with long latency, although patients may present for evaluation after an acute exposure. Referral for follow-up surveillance is appropriate if exposure is anticipated to be long term. 

Australian gold miners are vulnerable to dengue fever (a mosquito-bome acute infectious viral disease characterized by headache, severe joint pain, and rash), silicosis (massive fibrosis of the lungs marked by shortness of breath and caused by inhalation of silica dusts, usually SiOi), and phthisis (a historical term used to describe a wasting condition, possibly pulmonary tuberculosis). 

Technological advances have made unintended consequences almost inevitable. Like a phantom in a bag that pops out in every direction that isn t held, secondary effects that are masked by primary effects assume much more importance when the primary effects are conquered (Tenner, 1996). Chronic illnesses such as cancer, silicosis, and cumulative trauma disorder probably were not recognized as important because acute illnesses such as typhoid, plague, and pneumonia killed so many. After anesthetics allowed painless surgery, the number of surgical procedures skyrocketed and the total amount of pain experienced by the total human population is higher because of it. 

Examples Silicosis, asbestosis, pneumonitis, pharyngitis, rhinitis or acute congestion farmer s lung, beryllium disease, tuberculosis, occupational asthma, reactive airways dysfunction S5mdrome (RADS), chronic obstructive pulmonary disease (COPD), hypersensitivity pneumonitis, toxic inhalation injury, such as metal fume fever, chronic obstructive bronchitis, and other pneumoconioses. 

Dorentrup quartz powder causing fatal acute silicosis a 25-years-old woman packing scouring powder for 2 /2 years induced miliary hepatic granulomas composed of macrophages containing crystalline siUca (Giese 1931). 

Accelerated Silicosis and Silicoproteinosis (Acute Silicosis) Classical chronic silicosis takes many years to decades to manifest. However, some patients develop more rapid disease. In accelerated silicosis, there are more cellular nodules that may have a more granulomatous appearance. These consist of histo-cytic cells enmeshed in a variable amount of mature and immature collagen and reticulin. Hyalinization and circular orientation of the collagen fibers may be seen but are not as well developed as in classic chronic silicosis. 

Acute silicosis, or silicoproteinosis, is caused by exposure to high concentrations of freshly fractured... 

Doll R (1987) 8ymposium on MMMF, Copenhagen, Oct 1986 overview and conclusions. Ann Occup Hyg 31 805-819 Dumontet C, Biron F, Vitrey D (1991) Acute silicosis due to inhalation of a domestic product. Am Rev Respir Disl43 880-882... 

Brown GP, Monicj M, Hunninghake GW (1988) Fibroblast proliferation induced by silica-exposed human alveolar macrophages. Am Rev Respir Dis 138 85-89 Buechner HA,Ansari A (1969) Acute silico-proteinosis. A new pathologic variant of acute silicosis in sandblasters, characterized by histologic features resembling alveolar proteinosis. Dis Chest 55 274-278... 

Hoffmann EO, Lamberty J, Pizzolato P et al (1973) The ultrastructure of acute silicosis. Arch Pathol 96 104-107 Honma K, Vallyathan V (2002) Rheumatoid pneumoconiosis a comparative study of autopsy cases between Japan and North America. Ann Occup Hyg 465 265-267 Honma K, Abraham JL, Chiyotani K et al (2004) Proposed criteria for mixed-dust pneumoconiosis definition, descriptions, and guidelines for pathologic diagnosis and clinical correlation. Hum Pathol 35 1515-1523 Hughes JM, Jones RN, Gilson JC et al (1982) Determinants of progression in sandblasters silicosis. Ann Occup Hyg 26 701-712... 

Michel RD, Morris JF (1964) Acute Silicosis. Arch Intern Med 113 850-855... 

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