Zeolite
Classification:
Zeolites are alumosilicate minerals, which have a framework structure enclosing cavities occupied by large ions and water molecules. These have a considerable freedom of movement permitting ion exchange and reversible dehydratation; compare to brewsterite, chrysocolla, clinoptolite, dachiardite, desmine, epistilbite, erionite, ferrierite, gonnardite, laumontite, mordenite, me solite, natrolite, offretite, scolezite, stilbite, thomsonite. A related mineral is analcite.
Structure:
All zeolites are built by groups of silicon or aluminum atoms in a tetrahedral oxygen configuration. The tetrahedra are linked by sharing all oxygen atoms. Large cavities and channels contain the cations. These are relatively loosely bond and induce a broad variation of chemical composition. The structural differences between the members of the zeolite groups are related with the various linkages of the rings of tetrahedra.
Crystallographic Constants:
As listed under the specific headings.
Crystal Group:
As listed under the specific headings.
Color:
As listed under the specific headings.
Optical Properties:
As listed under the specific headings.
Pleochroism:
As listed under the specific headings.
Powder Diagram:
As listed under the specific headings.
Natural Sources:
Bulgaria, China, Cuba, Slov. Rep./Czec. Rep., Germany, Great Britain, Hungary, Italy, Yugoslavia, Japan, Korea, Mexico, Romania, the RSA, Russia, Turkey, and the USA. They are normally created in pyroclastic rocks (e.g. tuff).
Medical Importance:
Key Hazards:
Possibly Fibrogenic, possibly mutagenic, carcinogenic.
Involved Organs:
Lung, pleura.
Exposure/Epidemiology:
Exposure may occur in mining; zeolites are used as adsorption agents and molecular sieving, detergents, catalysts, in cement, lightweight building block, paper industries, in wastewater treatment, water filtration, and animal litter. World production of zeolites was estimated to 300 000 tons/year. High rates of mesotheliomas (800/100 000) have been described from some villages in Turkey and are related to erionite.
Thresholds: |
TWA |
STEL |
|
mg/m3 |
mg/m3 |
| Germany | 6 | |
| Russia | | 2 |
Synonyms/Trade Names:
Brewsterite, Chrysocolla, Clinoptolite, Dachiardite, Desmine, Epistilbite, Erionite, Ferrierite, Gonnardite, Laumontite, Mordenite, Mesolite, Natrolite, Offretite, Scolezite, Stilbite, Thomsonite.
Chemistry/Composition:
The general zeolite formula is: ((M+,M2+0.52)x×(SiO2)y×(H2O)z with M+: e.g. alkali metal cations, M2+: e.g. alkaline earth cations .
Etiology/Pathophysiology:
Zeolites can be of fibrous form and induce mesothelioma similar to asbestos . Fibrogenic effects were seen after peritoneal injection of erionite and mordenite in animal experiments (rats).
Lung Diseases:
Diffuse interstitial fibrosis, pleural effusions, pleural plaque, lung cancer and mesothelioma are known to be induced by erionite. For details, see under the heading asbestos .
Clinical Presentation:
Chronic cough and shortness of breath during physical exercise are usually the first symptoms; chest pain is often associated with pleural tumors.
Radiology:
Chest radiographs are often normal in patients with early changes. Others may display diffuse interstitial densities, pleural thickening, or effusion.
Lung Function:
Progressive restrictive changes or severe obstructive alterations are seen.
Bronchoalveolar Lavage:
The inhaled mineral fibers can be analyzed and quantified in the lavage fluid. Increased levels of complement C5, or altered ratio of the T4/T8 lymphocytes correspond with the activity of the fibrotic lesions.
Pathology:
Gross:
The lungs may display an increased consistency, a thickened and fibrotic pleura, honeycombing, or circumscribed white-yellowish tumor masses. For details, see under the heading asbestos .
Histology:
The fibers are birefringent and often coated with iron-protein mucopolysaccharide substances (asbestos bodies). They are usually deposited in the distant airways and can be ingested by macrophages. Diffuse interstitial fibrosis associated with scattered mononuclear inflammatory infiltrates and acellular collagenous fibers in the pleura are common findings. Benign and malignant tumors of various cell types (most frequently common lung carcinoma and mesothelioma) can develop. For details, see under the heading asbestos .
Prognosis:
Usually poor due to serious sequelae.
Additional Diseases:
See under the heading asbestos .
Remarks:
Most man-made zeolites have no fibrogenic and carcinogenic potency.
References:
search Pubmed for Zeolite
Baris YI, Artvinli M, Sahin AA, Sebastien P, Gaudichet A: Diffuse lung fibrosis due to fibrous zeolite (erionite) exposure. Eur J Respir Dis 70 (1987) 122-125
Bignon J: Lung Diseases and non-asbestos fibres. Eur J Respir Dis Suppl 126 (1983) 397-402
Craighead JE: Asbestos-associated diseases. Arch Pathol Lab Med Special Issue 106 (1982) 579-597
Dail DH, Hammar SP: Pulmonary pathology. Springer, New York, Berlin Heidelberg (1988)
Davis GS, Calhoun WJ: Occupational and environmental causes of interstitial lung disease. In: MI Schwarz, TE King (Eds): Interstitial lung disease. BC Decker, Toronto, Philadelphia (1988) 63-109
Durnev AD, Suslova TB, Cheremisina ZP, Dubovskaia OIu, Nigarova EA, Korkina LG, Seredenin SB, Velichkovskii BT: The mutagenic action of the dust of natural zeolites and chrysotile asbestos . Eksp Onkol 12 (1990) 21-24
Erzen C, Eryilmaz M, Kalyoncu F, Bilir N, Sahin A, Baris YI: CT findings in malignant pleural mesothelioma related to nonoccupational exposure to asbestos and fibrous zeolite (erionite). J Comput Assist Tomogr 15 (1991) 256-260
Feigin DS: Misconceptions regarding the pathogenicity of silicas and silicates. J Thorax Imaging 4 (1989) 68-80
Förster H: Eine mineralogisch-petrologische Untersuchung über mögliche Ursachen von Mesotheliomen in Kappadokien/Türkei. Zbl Arbeitsmed 32 (1982) 18-27
Gottardi G, Galli E: Natural zeolites. Springer, Berlin (1985)
Hansen S: A series of hypothecical building units generating open zeolite-type nets. Naturwiss 77 (1990) 581-584
Hill RJ, Edwards RE, Carthew P: Early changes in the pleu ral mesothelium following intrapleur al inoculation of the mineral fibre erionite and the subsequent development of mesotheliomas. J Exp Pathol Oxford 71 (19909 105-118
Jones JSP: Pathology of the mesothelium. Springer, London, Heidelberg (1987)
Kayser K: Analytical Lung Pathology. Springer, Heidelberg, New York (1992)
Kruglikov GG, Velichkovskii BT, Garmash TI: Morphology of pneumoconiosis induced by natural zeolite. Gig Tr Prof Zabol (1990) 14-17
Özesmi M, Parra Karlson A, Hillerdal G, Forsum U: Phenotypic characterization of peripheral blood lymphoid cells in people exposed to fibrous zeolite. Br J Ind Med 43 (1986) 830-833
Özesmi M, Hillerdal G, Svane B, Widstrom O: Prospective clinical and radiological study of zeolite-exposed turkish immigrants in Sweden. Respiration 57 (1990) 325-328
Passaglia E, Galli E: Natural zeolites. Mineralogy and apllications. Eur J Mineral 3 (1991) 637-640
Pylev LN, Kulagina TF, Grankina EP, Chelishchev NF, B erenshtein B G: Carcinogenicity of zeolitephillipsite. Gig Sanit (1989) 7-10
Rom WN: Fibrous zeolites. In: WH Rom (Ed): Environmetal and occupational medicine. Litttle, Brown and Comp, Boston (1983)
Sand LB, Mumpton FA: Natural zeolites. Pergamon Press, Oxford (1978).
Short SR, Petsonk EL: Respiratory health risks among nonmetal miners. Occup Med 8 (1993) 57-70
Smith JV: Structural Classification of zeolites. Min Soc Am Spec Pap 1 (1963) 281-290
Spurny KR: Natural zeolites and their carcinogenity a review. Sci Total Environ 30 (1984) 147-66
Suzuku Y: Carcinogenic and fibrogenic effects of zeolites: preliminary observations. Environ Res 287 (1982) 433-445
Suzuki Y, Kohyama N: Malignant mesothelioma induced by asbestos and zeolite in the mouse peritoneal cavity. Envrion Re 35 (1984) 277-292
Tatrai E, Wojnarovits I, Ungvary G: Non-fibrous zeolite induced experimental pneumoconiosis in rats. Exp Pathol 43 (1991) 41-46
Tatrai E, Bacsy E, Karpati J, Ungvary G: On the examination of the pulmonary toxicity of mordenite in rats. Pol J Occup Med Environ Health 5 (1992) 237-243
Urano N, Yano E, Evans PH: Reactive oxygen metabolites produced by the carcinogenic fibrous mineral erionite. Environ Res 54 (1991) 74-81
Vrzgula L, Seidel H: Absorption characteristics of natural zeolite (clinoptilolite) in biological material in vitro. Vet Med Praha 34 (1989) 537-544
Werner I, Karpati J: Mineralogische Charakterisierung eines natürlichen ungarischen Zeolits. Staub Reinh Luft 48 (1988) 169-171