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FILE NAME Talc TALC DATE 1979 DOC TALC165 DOCUMENT DESCRIPTION Book Chapter - Fibrous Mineral Content of Consumer Containing Products Dusts Desiese 1979 ET iments CC J its with anized 17-652 ts Brit d other FIBROUS MINERAL CONTENT OF CONSUMER CONTAINING PRODUCTS A. Rohl and A. M. Langer Environmental Sciences Laboratory Mount Sinai School of Medicine City University of New York New York New York 10029 INTRODUCTION Approximately 800,000 tons of raw talc are produced annually in the United States Talc is used in a number of industries for a variety of purposes e.g. the manufacture of ceramics paints paper rubber roofing insecticides stucco plastics textiles and soaps Wells 1978 Pulverized talc is also used on a much smaller tonnage basis as an ingredient in such consumer products as cosmetic talcums paper mache and modeling compounds in spackling patching compounds and putties in automotive and boat body repair fillers and caulking compounds The uses of talc in food products include rice coating peanut polishing candy molding and salami dusting It is also used a as filler and excipient for pharmaceutical pills and for dusting contraceptive diaphragms Undoubtedly there are other uses of talc in consumer products which are not generally known Each product carries with it a distinct and individual inhalation and ingestion potential of the mineral components The present report will deal with our studies of four types of these products specifically talcum powders spackling and patching compounds coated rice and modeling materials We have studied talc in other types of consumer products but these four categories represent the varietal range of applications It was our purpose to examine these materials to determine the presence or absence of minerals with known or suspected disease potential specifically the fibrous amphiboles quartz and the asbestos of mineral chrysotile L GEOLOGICAL OCCURRENCE OF TALC oe Talc rocks occur fairly commonly in nature and are formed as the result of two important geological processes i.e. the hydrothermal alteration of ultramafic rocks and the low grade thermal metamorphism of silica dolomite CaMg These metamorphic processes frequently result in the formation of an assemblage of existing minerals principally hydrous magnesium silicates but also hydrous magnesium silicates Some of these are the magnesium and calcium amphibole minerals which include anthophyllite and tremolite and the serpentine minerals including chrysotile asbestos Depending on the nature of the parent rock varying amounts of mica minerals e.g. chlorite quartz and carbonates may also be found Table ) Although pure talc deposits exist very frequently the mineralogically complex deposits are used to provide talc for both industrial and consumer products The mineral talc is a layer sheet silicate with the empirical chemical The authors wish to acknowledge support in part by grant ES 00928 from The National Institute of Environmental Health Sciences ROHL AND LANGER TABLE 1. Minerals which are commonly found in talc deposits Carbonates Mineral Calcite Dolomite Magnesite Ideal formula CaCO CaMg MgCO3 Amphiboles Tremolite Anthophyllite C"M^ S,,""22 S022 Serpentine Antigorite Chrysotile uncommon Lizardite uncommon Mg3S1205 Mg3S1205 4 Mg3S1205 Others Quartz Mica e.g. Phlogopite Chlorite e.g. Penninite SiO2 SA20204 8020 OH 16 taeten caerhe fenreavzet Sare wegen Gnae. tg natal 2 Vor)sf atemie > ot yera ad a 20 a formula Mg However aluminum Al or titanium Ti may substitute for silicon Si and iron Fe manganese Mn nickel Ni chromium Cr cobalt Co etc. may substitute for magnesium Trace metal contamination is common One talc deposit in the eastern United States containing up to 0.2 Ni and substantial amounts of Cr and Co has been used as a source of consumer talcums for many years The layers of talc are very weakly bound to one another and this accounts for the ease with which it breaks into sheets or platy fragments This excellent cleavage combined with high surface area softness and light color make talc important as both an industrial and consumer material The geology and mineralogy of talc have been extensively reviewed elsewhere Rohl and Langer 1974 Rohl et al 1976 ANALYTICAL TECHNIQUES FOR IDENTIFICATION CATION OF FIBROUS MINERALS IN TALC AND QUANTIFI- Techniques which have been successfully used for the analysis of mineral fibers in talc products include optical microscopy ray diffractometry and electron beam instrumentation The use of polarized light optics has long been a standard technique for the identification of minerals By using immersion oils of known refractive indices for example the optical properties of unknown crystalline particles can be determined However there are a number of conditions which limit the usefulness of optical microscopy The accurate determination of refractive indices is extremely difficult when applied to particles less than 1 min diameter The optical properties of fibrous minerals frequently obviates full characterization of their optical constants In consumer talc products most of which are finely pulverized powders the particle dimensions are at or below the resolution capability of optical microscopy making LANGER itute for alt Co One talc stantial ir many unts for avage tant as Ic have 976 INTIFInineral lectron for the es for mined optical difficult ties of ints in Jar nah ASBESTIFORM CONTENT OF TALC 395 identification very difficult if not impossible Large numbers of fibers may go undetected when this technique is used exclusively Stanley and Norwood 1973 However it may be useful in some cases at least as a screening or preliminary technique ray powder diffraction has been used in both the continuous scan and scan modes of operation for the identification and quantitation of fibrous minerals in talc Rohl and Langer 1974 Rohl et al 1976 Stanley and Norwood 1973 This can be achieved by comparison of dilutions of known minerals in a talc matrix with unknowns Quantitative analysis using this technique requires 1 a talc standard or matrix completely free of contaminating minerals and pure standards of fibrous minerals for preparing fiber dilution standards 2 a preparation method which is both sensitive and reproducible and 3 selection of diagnostic ray reflections for quantitative analysis of specific minerals ray diffraction in the scan mode is used for quantitative determination of tremolite chrysotile and anthophyllite in talc at levels as low as 0.1 0.25 and 2.0 by weight respec- tively Rohl and Langer 1974 Rohl et al 1976 These minerals are often found as grained and intimate components of talc rock and they are of particular concern as constituents of consumer talc products because of their biological potential Daymon 1946 Dreessen 1933 Dreessen and Dalla Valle 1935 Kleinfeld and Messite 1960 Kleinfeld et al 1955 1967 1973 Mclaughlin et al 1949 Millman 1947 Noro 1946 Porro and Levine 1946 Porro et al 1942 Reichman 1944 Schepers 1965 Siegal et al 1943 The major limitation of ray diffraction analysis is its inability to distinguish between different morphological habits of the same mineral For example short tremolite fragments and long fibers of asbestiform tremolite give virtually identical ray patterns To distinguish between different habits or shapes of the same mineral including asbestos minerals requires microscopic techniques Transmission electron microscopy used in conjunction with selected area electron diffraction SAED provides the resolution capability to visualize all particles and in many cases to identify them For example at magnifications of about 25,000x or greater chrysotile fibers may be identified on the basis of their unique morphology In some instances the morphological similarities between fibrous talc and amphibole fibers may be close enough to preclude the unequivocal identification of the latter on the basis of such characteristics as cleavage diffraction contrast figures and aspect ratios However talc fibers can be easily distinguished from amphibole fibers on the basis of SAED patterns CONSUMER PRODUCTS STUDIES Consumer Talcums and Powders In a paper published in 1976 we reported a mineral and chemical chacterization of 20 consumer talcums and powders obtained in New York city during the period 1971-1975 Rohl et al 1976 Where known all were formulated prior to 1973. Of the twenty products 10 contained either tremolite or anthophyllite or both The proportions determined by scan ray diffraction ranged from 0.1 to over 14 by weight No attempt was made to distinguish proportions of fibrous and fibrous morphological phases although every sample contained fiber Two contained detectable amounts of chrysotile The presence of these minerals in fibrous form was verified by electron beam techniques Figures 1,2 ee eenenenenememenemanecennceenesaceemnenatil 396 ROHL AND LANGER laa} =} & ; oe 'o S Tag OTS i He B (ea DERE, Patthe a vali : am * aah Rldy SiO OMENS Tye w& etepaces 4 iy ill: PRS Ae whi oc g 5 Bg eie a SCOR SAU EIT Se SSO : untt TSE ae SIN BR , Oa ES Nai RES SSREGO FIGURE 1. Electron photomicrograph of amphibole fibers in cosmetic talcum powder magnification x25,000 NGER ASBESTIFORM CONTENT OF TALC Boe were ERED, LEERIS Gee OS CA TGS NOR Z 397 00 ike Ass Ws:i yaie a hy zna +3p% ps ey : G FIGURE 2. Electron photomicrograph of amphibole fibers in cosmetic talcum powder magnification x52,000 an Se SEEee. a eee5 aeee oe 228 tel Utne Ea aint BND 398 ROHL AND LANGER Quartz was found in eight samples with seven ranging from 2 to % and one as high as 35 Chemical determinations including bulk chemistry and trace metals were also made on the twenty samples Four samples showed systematically high levels of nickel chromium and cobalt with average values in parts per million of 890 518 and 57 respectively The mean concentrations of nickel chromium and cobalt in the other 16 samples were 18 29 and less than 3 respectively A study by this laboratory of cosmetic talcums purchased during the period 1975-1978 is in progress Preliminary results suggest that fewer products contain fibrous minerals Spackling and Patching Compounds Spackling and patching compounds consist of grained powders or premixed pastes The ingredients usually are plaster of paris limestone talc clays micas or some other type of pulverized rock filler Chrysotile is added to some products to provide reinforcement and to control shrinkage and cracking as it cures Fibrous amphibole minerals are found in some products because they occur naturally in talc carbonates and other raw materials In a paper published in 1975 the mineral content of 15 consumer spackling compounds purchased during the period 1972 to early 1974 was reported Rohl et al 1975 Two products contained talc as major components and one of these also contained about 4 to % by weight of tremolite Chrysotile was found in three products ranging from 5 to 10 by weight Another product consisted principally of anthophyllite 10-12 and quartz Quartz was found in nine products in proportions ranging from 5 to 70 by weight Optical and electron microscopic analyses showed that the asbestos and other mineral fibers ranged in length from 0.25 to 8.0...mFigure 3 Almost all were shorter than 5 ...mlength which is of respirable size yet they were not detected by optical microscopy The paper also reported the results of mineral analyses of 10 industrial taping compounds used in drywall building construction Nine of ten contained chrysotile in about the same proportions 5-12 as the consumer products Air measurements made during mixing sanding and clean of drywall taping showed that airborne concentrations of two fibers per milliliter of air or more were common Electron microscopic analyses of the air samples showed that for every fiber visible by light microscopy x400 magnification from 200 to 1,000 fibers could be seen at magnifications of x 25,000 In the follow to this study during 1975 five different consumer spackling compounds were obtained and analyzed Of the five four had talc present as a major phase and also contained tremolite or anthophyllite ranging from 2 to 12 by weight Chrysotile was also found in three of the five products in proportions ranging from 5 to 15 . The latter concentrations reflect chrysotile as an additive not as a talc contaminant Talc - Coated Rice The practice of coating short grain and medium grain rice has been common in the United States for over 50 years Several explanations for this practice have been advanced The principal reason given for coating rice is to give an appealing smooth and shiny luster to the product Puerto Rican Oriental and Hawaiian consumers reportedly show a decided preference for coated rice It has also been claimed that coated rice better withstands insect and fungal infestation and maintains moisture stabilization The U.S. Department of Agriculture statistics indicate that about 300 million pounds of coated rice were distributed in the 48 conterminous states in 1972 and ASBE LANGER one as metals ally high illion of ium and e period contain ASBESTIFORM CONTENT OF TALC 399 or pre- ; clays o some it cures / occur In 1975 ing the ntained weight % by qu Wel .L s and all were cted by s of 10 of ten sumer drywall more hat for 1 fibers during alyzed olite or ree of rations non been nooth umers d that isture nill ! and RE Easbrit :& Sears ave Ba Tied x52,000 / FIGURE 3. Electron photomicrograph of chrysotile fibers in consumer spackling compound magnification The fibers are all less than 5 min length Other particles are plasteorf Paris talc and mica platelets e ee e eS wer ume YS WV LARSel st h Set 400 ROHL AND LANGER that an additional 470 million pounds were distributed to the Territories and the State of Hawaii that year Federal Register 1977 The total of 700 million pounds of coated rice represents about third of the rice sold in the United States and its Territories annually Approximately one pound of talc is used for coating 100 pounds of milled rice Two samples of talc powder which are used for the coating of rice that raw powders were obtained from rice dealers Five samples of coated rice were purchased from local grocery stores Three duplicate purchases were made Standard weights of rice samples were washed twice in known volumes of water Prior to rinsing the water used for washing the rice was passed through an absolute filter to remove any adventitous mineral contamination After each rinse the wash water was passed through a 0.4 mmembrane filter to remove insoluble material The material retained was dried weighed and ashed in nascent oxygen to remove organic substances then reweighed These residues and the two raw talc powders were prepared and scanned for diagnostic asbestos reflections by ray diffraction according to procedures described by Rohl et al 1976 In addition polarizing optical microscopy transmission electron microscopy and microprobe techniques were used to verify and further characterize the minerals present Quantitative analysis of talc coating showed that one of the two samples of talc powder contained tremolite on the order of % by weight Three of the eight rice coating residues were also found to contain tremolite and anthophyllite up to % by weight and averaging about % Another rice residue contained about 20 of a fibrous amphibole mineral with a chemical composition similar to glaucophane In four samples amphiboles were not detected by ray diffraction However analyses by transmission electron microscopy and microprobe showed that three contained trace amounts of asbestiform amphibole minerals Chrysotile was not detected in any samples Eleven samples of grain rice were purchased by colleagues in various cities in the United Kingdom where much of the rice is imported from Australia and Italy The washings of these samples of rice were found to contain no talc One sample coating was found to be calcium carbonate containing Modeling Materials Arts and crafts or modeling materials consist of dry powders often mixtures of plaster of paris or gypsum or calcium carbonate or talc with fibrous minerals including chrysotile tremolite and anthophyllite These powders are mixed with water and then cast or shaped into figures In the school year 1971-1972 The New York City Board of Education had purchased 50,000 packages of paper mache - type material each package containing five pounds The product upon analysis was found to contain about 50 chrysotile As a result use of the product was discontinued in New York City schools The material which was subsequently submitted for it consisted of a mixture of plaster and talc including 15 to 20 tremolite and anthophyllite Thereafter this material was discontinued as well Six other commerical samples of arts and crafts materials some marketed specifically for school children were analyzed for their mineral content Of the six three contained talc and also tremolite and chrysotile The asbestos and fibrous mineral content of the samples exceeded 10 by weight Figure 4 NGER State ds of nd its 100 raw were andior to ter to vater en to talc is by addi- icro- ent ftalc rice 6,1 of e In yses .ined .ined in ed ed es in from no ASBESTIFORM CONTENT OF TALC eyebsas 401 401 Pa:BDnGe) F270 ey HY 2 : es of erals with had ain50 City of lite ete the and i ReNSs: REE OSRse wey SI Sony Ya saeNS eShSSi oye POCRAs yasPPEL CONeas a7 SUIDEU Toate errs = yn aes aeye FIGURE 4. Electron Photomicrograph of asbestiform amphiboles in dry type modeling compound x35,000 magnification :2 Bo |} cust pet8y Rion ata ' Shut 402 ROHL AND LANGER CONCLUSIONS Some of the studied consumer products which contain talc have been found to contain varying amounts of natural mineral contaminants some of which have been demonstrated to be biologically active in humans These minerals include chrysotile anthophyllite tremolite and quartz In addition a number of trace metals were detected in forms essentially unknown It is therefore recommended that 1. The significance of these materials in consumer products be evaluated on a systematic clinical or epidemiological basis Heavy intermittent or habitual use of these products with high levels of fibrous mineral fibers may produce disease For example recognition of this possibility has led to efforts by the cosmetic talcum industry to reduce or eliminate contaminated products by changing their sources of raw materials 2. Air measurements taken during drywall construction suggest that using consumer spackling and patching compounds during home repair work could expose members of entire households to high concentrations of dust An assessment of the risk to consumers was made by the Consumer Product Safety Commission in proposing rules to regulate patching compounds Blejer and Arlon 1973 It was calculated that for a conservative yearly exposure of four hour days the increased risk of death from respiratory cancer from even such a modest exposure would be unaccept- able 3. While some investigators have proposed that the ingestion of fibercontaminated talc products may pose a hazard of increased neoplastic risk especially of the intestinal tract Hammond et al 1965 Henderson et al 1975 Matsudo et al 1974 Merewether 1930 Selikoff et al 1967 this disease potential is presently unknown coated rice frequently constitutes a staple of the diet of many Americans and one kilogram per week of talc could be consumed by some individuals Since several of the talc coatings analyzed contained up to % and % amphibole minerals some individuals could ingest about 600 milligrams per week of these mineral contaminants Approximately 9.4 grams of talc would be ingested at the same time The coating of rice with talc should be reviewed with the aim of eliminating it or substituting coatings that do not contain these suspect minerals . 4. The presence of unbound asbestos fibrous and quartz minerals of respirable size in arts and crafts materials especially those used by children with their long life expectancy represents in our view an unacceptable exposure These should be eliminated from such products immediately Artists artisans and hobbyists may also be exposed to these materials as well as to similar dusts generated during sculpting of talc or steatite rock These individuals should be made aware of hazards associated with such exposures and should protect themselves accordingly ASBES R Blejer } Med Daymor Dreess Dreess Publ Federal V 42 Hammo with Hender from Kleinfel Kleinfel Yort Kleinfel com Kleinfel 195 Matsud talc Mclaug Merewe worl Milimar Noro L I Porro Staf Porro 47 Reichm Rohl A 9.95 Rohl A and Rohl A spa Schep tum Selikof Siegal ger Stanle In Wells ton ER 2607 2607 2607 2607 16026 16026 16026 ted ing ork st ner m- tive om ept- ber- risk son 67 ently per the rals hese ed at aim pect is of 1 by cept- nedlateatite with ASBESTIFORM CONTENT OF TALC 403 REFERENCES Blejer H P. and Arlon R. Talc A possible occupational and environmental carcinogen Jour Occup Med 15 92-97 1973 Daymon H Latent silicosis and tuberculosis Amer Rev. Tuberculosis 53 554-559 1946 Dreessen W C Effects of certain silicate dusts in the lungs J. Indust Hyg 15 66.78 1933 Dreessen W.C. and Dalla Valle J.M The effects of exposure to dust in two Georgia talc mills and mines Publ Health Rpts 1405-1415 1935 Federal Register Proposal to Revise Standard for Enriched Rice by U S. Food and Drug Administration V no 136 July 15 1977 Hammond E.C. Selikoff I.J. and Churg .. Neoplasia among insulation workers in the United States with special to reference abdominal neoplasia Annal NY Acad Sci 132-519-525 1965 Henderson W.J. Evans D.M D. Davies J D. and Griffiths K Analysis of particles in stomach tumours from Japanese males Envir Research 240-249 1975 Kleinfeld M. and Messite .: Problem areas in pneumoconiosis Arch Environ Health 5.428-437 1960 Kleinfeld M. Messite J. Kooyman O. and Zaki M.H Mortality among talc miners and millers in New York State Arch Env Health 663-667 1967 Kleinfeld M. Messite J. and Langer A.M A study of workers exposed to asbestiform minerals in commercial talc manufacture Environ Res 6-132-143 1973 Kleinfeld M Messite J and Tabershaw I.R Talc pneumoconiosis Arch Indust Health 12-66-72 1955 Matsudo H. Hodgkin NM and Tanaka A : Japanese gastric cancer Potentially carcinogenic silicates taic from rice Arch Path 97-366-368 1974 Mclaughlin A. Rogers E. and Dunham K.C Talc pneumoconiosis 6 184-194 1949 Merewether E.R A The occurrence of pulmonary fibrosis and other pulmonary affections in asbestos workers J Ind Hyg 198-222 239-257 1930 Millman N. Pneumoconiosis due to talc in the cosmetic industry Occup Med 4.391-394 1947 Noro .: On the history of asbestosis Acta Path et microb Scandinavia 23-53-59 1946 Porro F.W. and Levine N.M Pathology of talc pneumoconiosis with report of an autopsy North N.Y State Med J 23-25 1946 Porro F.W. Patton J.R. and Hobbs A A Pneumoconiosis in the talc industry Am J. Roentgenol 507-524 1942 Reichman V Uber talkumstaublunge Arch f Gewerbepath and Gewerbehyg Rohl N and Langer A M Identification and quantitation of asbestos in talc 319-322 1944 Environ Health Persp 9.95-109,1974 9.95-109,1974 Rohl A.N al Consumer talcums and powders Mineral and chemical characterization J. Toxicology and Envir Health 255-284 1976 Rohl A.N , Langer A.M. Selikoff 1.J. 1.J. and Nicholson W J. J. Exposure to asbestos in the use of consumer spackling patching and taping compounds Science 551-553 1975 Schepers G WH Discussion of Newhouse M.L and Thompson H Epidemiology of mesothelial tumors in the London area Annals of NY NY Acad of Sci 579-602 1965 Selikoff I.J. et al Asbestosis and neoplasia Amer Jour Med 42-487-496 1967 Siegal W Smith R. and Greenburg .: The dust hazard in tremolite talc mining including roent- genological findings in talc workers Amer J. Roentgenolog 4 11-29 1943 Stanley H.D. and Norwood R.E The detection and identification of asbestos and asbestiform materials in talc Report Pfizer Inc , 1973 Wells JR JR Talc and pyrophyllite in 1976. Mineral facts and problems U.S Bureau of Mines Washing- ton DC DC U.S. Government Printing Office 1978 17 MCeen armnehldnd ah Se if Pas spiesRINK Siar Xe eReirae Bi SNe en amre mes Ser ban Ee Re RAE Ot Tet on gn Test eet ETC RE NE TE COPYRIGHT 1979 BY THE SOCIETY FOR OCCU- PATIONAL AND ENVIRONMENTAL HEALTH All rights Reserved NO PART OF THIS PUBLICATION MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM BY ANY MEANS ELECTRONIC OR MECHANICALLY INCLUDING PHOTOCOPY RECORDING OR ANY INFORMATION STORAGE AND RETRIEVAL SYSTEM WITHOUT PERMISSION IN WRITING PATHOTOX PUBLISHERS INC 2405 Bond Street Park Forest South Illinois 60466 Library of Congress Catalog Card Number 79-88819 79-8819 ISBN 0-930376-08-0 Printed in The United States of America SOCIET In Deceml Health Act cha in the workplac given low prior and decision w people and the protecting the t of the total envi Attemptst from newly dis surrounded the quate controls . In 1972 met in a series From these dis Health - a m ' examination of Represent from academia Independent m groups The m universal dime SOEH act Through its w communication often different problems By F scientific and s ing to the exa occupational a With the p hopes to expar living environm By focusing pu ing the dialogu professional ar working towarc