Bauxite

Classification:

Bauxite is a rock and the most important aluminum ore.

Cas:

1318-16-7

Synonyms/Trade Names:

Aluminiumerz, Bauxit; Bauxite lung.

Chemistry/Composition:

Bauxite is a mixed form of various minerals such as gibbsite, diaspore, boehmite, additional minerals, and quartz containng traces of aluminum .

Natural Sources:

Mined in Australia, France, Jamaica, Suriname, the USA, and Russia.

Medical Importance:

Key Hazards:

Fibrogenic, asthmatic-like reactions.

Involved Organs:

Lung

Exposure/Epidemiology:

Exposure may occur during mining and processing of the ore; it is used in the manufacture of abrasives. World production of bauxite was 80.5×106 t in 1976.

Thresholds:	TWA	STEL
	mg/m³	mg/m³
Germany	6
Russia		6

Etiology/Pathophysiology:

Inhaled bauxite particles are ingested by macrophages and induce a diffuse interstitial fibrosis, probably by release of oxygen radicals.

Lung Diseases:

Diffuse, interstitial fibrosis.

Clinical Presentation:

Patients present with chronic cough and dyspnea.

Radiology:

Chest radiographs reveal a reticular pattern with nodular components, and emphysematous bullous changes.

Lung Function:

Usually mild to moderate restrictive changes.

Bronchoalveolar Lavage:

The activity of the interstitial fibrosis is associated with the T4/T8 lymphocytes ratio of lymphocytes, and the activated complement measured in the lavage fluid.

Pathology:

Gross:

The fibrotic and emphysematous altered lungs are of grayish -red color.

Histology:

Thick fibrotic acellular bundles with some scattered inflammatory infiltrates can be noted in the peripheral lung zones. Crystal clests are surrounded by dust-laden macrophages and scattered multinucleated giant cells. The lumen of the small arteries may be obliterated by organized thrombotic lesions.

Prognosis:

The interstitial fibrosis is usually slowly progressive.

Additional Diseases:

Additional Diseases are usually induced by metallic aluminum; for further information, see under the heading aluminum.

References:

search Pubmed for Bauxite

Kayser K: Analytical Lung Pathology. Springer, Berlin, Heidelberg New York (1992)
Khanna M, Stotzky G: Transformation of Bacillus subtilis by DNA bound on montmorillonite and effect of DNase on the transforming ability of bound DNA. Appl Environ Microbiol 58 (1992) 1930-1939
Molinini R, Pesola M, Digennaro MA, Carino M, Nuzzaco A, Coviello F: Pneumoconiosis in bauxite miners. G Ital Med Lav 7 (1985) 209-213
Townsend MC, Sussman NB, Enterline PE, Morgan W K , Belk H D, Dinman BD : Radiographic abnormalities in relation to total dust exposure at a bauxite refinery and alumina-based chemical products plant. Am Rev Respir Dis 138 (1988) 90-95