Attapulgite
Classification:
Attapulgite is a sheet silicate.
Cas:
12174-11-7
Synonyms/Trade Names:
Bergholz, Bergwolle, Fullererden, Lasselit, Palygorskite, Attacote,Attagel, Attasorb, Diluex, Min-U-Gel FG, Permagel, Pharmasorb-Colloidal, 2000/P-RVM, RVM-XG, X 250, Zeogel.
Chemistry/Composition:
(Mg,Al)2(OH/Si4O10)×2H2O+2H2O. There can be a variable content of Fe, Ti, Ca, Na, K or P .
Structure:
Its structure contains of SiO4 double chains, which are bonded by groups of Mg and Al octahedra. Water is partially bonded and partially added to The structure.
Crystallographic Constants:
1.27-1.28 1.79 0.52-0.53 92.14 95.46-95.50
90.000 (orthorhombic)
1.27-1.28 1.78-1.81 0.51-0.52 92.14 95.46-95.50
90.000 (monoclinic).
Crystal Group:
Orthorhombic, monoclinic.
Color:
White or gray.
Optical Properties:
ny=1.55.
Pleochroism:
Weak.
Powder Diagram:
10.4 6.36 4.46 4.14 (21-958).
Natural Sources:
Mined in Australia, France, India, RSA, Russia (Gorki), Senegal, Spain (Carceres, Torrejon), Turkey, and the USA (Attapulgus/Georgia). The world production was 1.1 million tons in 1983.
Medical Importance:
Key Hazards:
Possibly fibrogenic, mutagenic, possibly carcinogenic.
Involved Organs:
Probably lung.
Exposure/Epidemiology:
Exposure can occur in mining and production (drying, milling): Technically it is used in thermal and acoustic insulation, chemical industries, as adsorbent or adhesive, in animal food, in fertilizers, for filtering, in paints, in the paper industry, for roofs, in drilling muds, cosmetics, pharmaceuticals, and pesticides. The mutagenic potency could not confirmed. The urine of a woman treated with a drug containing attapulgite over 6 months contained 300 000 fibers/ml. Additional detailed data are not known. Pneumoconiosis was seen in one study; a high rate of lung cancer in a second one.
Thresholds:
In Germany, attapulgite is graded possible carcinogenic according to the class “III A 2” of the MAK
Classification:
(carcinogenic in animal inhalation experiments).
Etiology/Pathophysiology:
The fiber size of the French attapulgite ranges from 0.02-0.2 µm in diameter (mean 0.6 µm) with an average length of 0.8 µm. In vitro tests (intraperitoneally, rats) performed with fibers measuring >5 µm revealed a high rate of malignant tumors of the abdominal cavity. Mesothelioma could be induced by intrapleural injections (rats) according to various authors.
Lung Diseases:
Associated specific diseases are not known; however, the mineral is listed by the ISO, i.e., possibly fibrogenic and mutagenic forms exist; for details, see under the heading asbestos .
Clinical Presentation:
Symptoms are mild and include chronic cough or shortness of breath during exercise.
Radiology:
Chest radiographs are usually normal.
Lung Function:
Usually normal.
Bronchoalveolar Lavage:
The mineral fibers can be analyzed in the lavage fluid.
Pathology:
Gross:
The lungs display no abnormal findings.
Histology:
The mineral fibers are deposited in the distant airways, and can be ingested by macrophages, and transferred to the proximal lymph nodes. An increased number of intra-alveolar macrophages and mild mononuclear inflammatory infiltrates may be noted.
Prognosis:
Usually good and without serious sequelae.
Additional Diseases:
None.
References:
search Pubmed for Attapulgite
Begin R, Masse S, Rola-Plescynski M, Geoffroy M, Martel M, Desmarais Y, Sebastien P: The lung biological activity of American attapulgite. Environ Res 42 (1987) 328-339
Bignon J: Lung Diseases and nonasbestos fibres. Eur J Respir Dis Suppl 126 (1983) 397-402
Charritat JL, Corbineau D, Guth S, Meunier M, Pernin P, Pflieger H: Therapeutic evaluation of Mormoiron attapulgite in acute diarrheas of infants and children. Ann Pediatr Paris 39 (1992) 326-332
Garcia JG, Dodson RF, Callahan KS: Effect of environmental particulates on cultured human and bovine endothelium. Cellular injury via an oxidantdependent pathway. Lab Invest 61 (1989) 53-61
IARC: Attapulgite. In: Silica and some silicates. IARC Mono Eval Carcinog Risk Chem Human 42 (1987) 159-173
IARC: Overall evaluations of carcinogenicity: an updating of IARC monographs volumes 1 to 42. IARC Mono Eval Carcinog Risk Human Suppl 7 (1987)
IARC: Non-occupational exposure to mineral fibres. IARC Sci Publ 90 (1989)
Jaurand MC, Fleury J, Monchaux G, Nebut M, Bignon J: Pleural carcinogenic potency of mineral fibers (asbestos , attapulgite) and their carcinogenicity on cultured cells. J Natl Cancer Inst 79 (1987) 797-804
Jones JSP: Pathology of the mesothelium. Springer, London, Heidelberg (1987)
Kayser K: Analytical Lung Pathology. Springer, Heidelberg, New York, (1992)
Lemaire I: Selective differences in macrophage populations and monokine production in resolving pulmonary granuloma and fibrosis. Am J Pathol 138 (1991) 487-495
Lemaire I, St Jean M: Modulation of lungassociated natural killer activity by resident and activated alveolar macrophages. Immunol Invest 19 (1990) 27-40
Nadeau D, Fouquett Coture L, Paradise D, Khorami J, Lane D, Dunnigan J: Cytotoxicity of respirable dusts from industrial minerals: comparison of two naturally occuring and two man-made silicates. Drug Chem Toxicol 1-2 (1987) 49-86
Nolan RP, Langer AM, Herson GB: Characterisation of palygorskite specimens from different geological locales for health hazard evaluation. Br J Ind Med 48 (1991) 463-475
Perderiset M, Etienne LS, Bignon J, Jaurand MC: Interactions of attapulgite (fibrous clay) with human red blood cells. Toxicol Lett 47 (1989) 303-309
Pott F, Blome H, Bruch J, Friedberg KD, Rödelsperger K: Einstufungsvorschlag für anorganische und organische Fasern . Arbeitsmed Sozialmed Präventivmed 25 (1990) 463-466
Renier A, Levy F, Pilliere F, Jaurand MC: Unscheduled DNA synthesis in rat pleural mesothelial cells treated with mineral fibres. Mutat Res 241 (1990) 361-367
Rödelsperger K, Bruckel B, Manke J, Woitowitz HJ, Pott F: Potential health risks from the use of fibrous mineral adsorption granulates. Br J Ind Med 5 (1987) 337-343
Rom WN: Attapulgite and sepiolite. In: WN Rom (Ed): Environmental and occupational medicine. Little, Brown and Comp, Boston (1983)
Short SR, Petsonk EL: Respiratory health risks among nonmetal miners. Occup Med 8 (1993) 57-70
Wagner JC, Griffiths DM, Munday DE: Experimental studies of palygorskite dusts. Br J Ind Med 11 (1987) 749-763
Waxweiler RJ, Zumwalde RD, Ness GO, Brown DP: A retrospective cohort mortality study of males mining and milling attapulgite clay. Am J Ind Med 13 (1988) 305-315