Pyrite
Chemistry/Composition:
FeS. It can contain traces of Co, Ni, As, Sb, Tl, Cu, Au, Ag, or Zn.
Structure:
The iron atoms are placed in the corners and the center of a cube. The sulfur molecules are placed at the mid-points of the edges and centers of the cube.
Crystallographic Constants:
5.405 5.405 5.405 90.000 90.000 90.000.
Crystal Group:
Cubic.
Color:
Yellow.
Optical Properties:
In thin sections opaque.
Pleochroism:
None.
Powder Diagram:
1.63 2.71 2.43 2.21 (6-710).
Natural Sources:
World-wide.
Medical Importance:
Key Hazards:
Possibly fibrogenic and carcinogenic due to traces of silica.
Involved Organs:
Lung.
Exposure/Epidemiology:
Exposure may occur in mining and melting; technically, it is used in paints.
Thresholds:
In Germany, MAK 6 mg/m3.
Etiology/Pathophysiology:
Crystalline silica have a fibrogenic potency, which mainly depends on the size of the particle; for details, see under the heading silica.
Lung Diseases:
All silica Varieties are possibly fibrogenic and carcinogenic; for details, see under the heading silica.
Clinical Presentation:
Usually, the symptoms have an insidious onset and include chronic cough, shortness of breath during exercise, and progressive dyspnea.
Radiology:
Chest radiographs display typical signs of p-type pneumoconiosis.
Lung Function:
Usually, a combination of restrictive and obstructive changes is noted.
Bronchoalveolar Lavage:
The silica particles can be analyzed in the lavage fluid; for details, see under the heading silica.
Pathology:
Gross:
The lungs display an increased consistency, and several black to grayish circumscribed nodules of various sizes.
Histology:
The nodules are composed of concentric acellular collagenous fibers which display birefringent crystals at the outer boundary. For details, see under the heading silica.
Prognosis:
Fair, and depending upon the severity of exposure and amount and composition of inhaled silica.
Remarks:
Miners are especially exposed to pyrite impured by silica, and severe pneumoconiosis may develop.
References:
search Pubmed for Pyrite
Battista G, Belli S, Carboncini F, Comba P, Levante G, Sartorelli P, Strambi F, Valentini F, Axelson O: Mortality among pyrite miners with low-level exposure to radon daughters. Scand J Work Environ Health 14 (1988) 280-285
Collinet MN, Morin D: Characterization of arsenopyrite oxidizing Thiobacillus. Tolerance to arsenite, arsenate, ferrous and ferric iron. Antonie Van Leeuwenhoek 57 (1990) 237-244
Fontecave M, Jaouen M, Mansuy D, Costa D, Zalma R, Pezerat H: Microsomal lipid peroxidation and oxygen-radicals formation are induced by insoluble iron-containing minerals. Biochem Biophys Res Commun 173 (1990) 912-918
Franzinelli A, Gori R, Levante G, Belli S, Comba P, Sartorelli E: Respiratory disorders and Lung Function impairment in pyrite miners. Med Lav 6 (1989) 479-488
Governa M, Valentino M, Tosi P, Luzi P, Miracco C, Sartorelli E, Loi F, Franzinelli A, Gori R: Pulmonary alveolar lipoproteinosis in rats following intratracheal injection of pyrite particles. J Toxicol Environ Health 19 (1986) 403-412
Green FHY, Yoshida K, Fick G, Paul J, Hugh A, Green WF: Characterization of airborne mineral dusts associated with farming activities in rural Alberta, Canada. Int Arch Occup Environ Health 62 (1990) 423-430
Hain E, Korallus U: Lungenkrebs durch arsenhaltigen Schwefelkies bei der Schwefelsäureherstellung-ein arbeitsmedizinisc hes Altlastenproblem. Zbl Arbeitsmed 42 (1992) 266-276
Kassirer JP, Kopelman RI: Iron pyrite and diagnostic confirmation. Osp Prac (Off) 5 (1989) 19, 22, 25
Koelsch F: Handbuch der Berufskrankheiten. Fischer, Jena (1972)
Larsson L, Olsson G, Holst O, Karlsson HT: Pyrite oxidation by thermophilic archaebacteria. Appl Environ Microbiol 56 (1990) 697-701
Pertuzzo GF, Sa la C: The respirable fraction: measurement and characterization. Med Lav 80 (1989) 71-77 (italian)