Coal dust exposure

Various studies have examined the incidence of gastric cancer with coal dust exposure because various carcinogenic substances have been identified in coal and because coal dust may reach the gastrointestinal tract through the pulmonary clearance system. Although... 

Lunsford RA, Okenfuss JR, Shulman SA. 1987. Diesel exhaust/coal dust exposure study Characterization of selected vapor-phase organic emissions. Government Reports Announcements and Index 13 . NTIS PB87-162889. 

Oryszczyn MP, Godin J, Frette C, et al. 1996. Decrease in selenium status in relation to coal dust exposure. Am J Ind Med 30 281-284. 

Kizil, G.V. A.M. Donoghue (2002). Coal dust exposures in the longwall mines of New South Wales, Australia a respiratory risk assessment. Society of Occupation Medicine 52 (3) 138-149. 

There is some evidence that coal-dust exposure causes centrilobular emphysema, based on postmortem lung sections, there being a relationship between emphysema score and lung-dust burden (Cockcroft et al. 1982). The relationship is easier to demonstrate when dust-related fibrosis is present (Ruckley et al. 1984). The relationship between emphysema score and lung-dust burden is stronger in non-smokers than smokers (Leigh et al. 1994). 

Kuhn DC, Stanley CF, El-Ayouby N, Demers LM. Effect of in vivo coal dust exposure on araehidonic acid metabolism in the rat alveolar macrophage. J Toxicol Environ Health 1990 29 157-168. 

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). 

In addition to the aforementioned dusts and fibers, coal mine dusts may also stimulate oxygen radical production [199], In this case hydroxyl radical production and lipid peroxidation also correlated well with the content of available surface iron. It has been proposed that free radical-mediated processes can be a casual cause of coal workers pneumoconiosis due to exposure to coal dusts. 

In limited studies coal dust did not increase the incidence of tumors in rats. There was no evidence of mutagenicity after exposure of rodents by inhalation or oral gavage. ... 

Lung fibrosis occurs with a buildup of fibrous material inside lung cavities. The fibers are rich in collagen, the tough, fibrous protein that gives strength to bone and connective tissue. Chronic fibrosis can result from pulmonary exposure to aluminum dust, aluminum abrasives, chromium(VI), coal dust, kaolin clay dust, ozone, phosgene, silica, and finely divided mineral talc. 

As is the case with the skin, the lungs are in constant contact with the external environment [16]. Exposure to the toxins in cigarette smoke is one of the most common causes of congestive, obstructive damage in the respiratory system. Occupational exposure to asbestos and medically necessary exposure to drugs such as cyclophosphamide and carmustine can also cause lung injury. Inhalations of coal dust and cotton fibers are other occupational hazards to the lungs. 

The focus of current scientific and regulatory activities is on engineered or synthetically produced substances with nanoscale dimensions. There are numerous naturally occurring nanoscale components of substances such as mineral deposits and volcanic dust, and in byproducts of common processes such as diesel exhaust and byproducts of coal combustion. Although exposure to these nanomaterials may be minimal and controlled in most cases, studies on such common nanomaterials as fog, coal dust, and ultrafine aerosols have provided useful information as to exposure and effects of particles this small, and these results are useful in predicting the properties of engineered nanoparticles. 

Examples of serious harm to workers from materials used and made in the manufacturing workplace are well known black lung disease and asbestosis stand out by the number of people affected and the severity of the results to long-term exposure to coal dust and asbestos fibers, respectively. Thus it is logical that, when dealing with bulk drugs (chemicals with potent and multiple biological activities), and as with thermochemi-... 

Miller, B.G. (1985). Dust exposure, pneumoconiosis, and mortality of coal miners. British Journal of International Medicine 723-733. 

In animal experiments the inhalation of soot increased mucus formation (Knauff 1867, Gross 1927). In rabbits and mongrel dogs kept underground in a bituminous coal mine (about 50 mg coal dust/m ) nearly continuously for up to 6 years, Schiller (1958) found a hypertrophy of the bronchial epithelium with a prevalence of goblet cells after 3 years exposure, but an atrophy at 6 years exposure. In the bronchioles, Clara cells showed an increase in apocrine secretion. 

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