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0641629 Asbestiform and/or Fibrous Minerals in Mines, Mills, and Quarries U.S. Department of Labor Ray Marshall, Secretary Mine Safety and Health Administration Robert B. Lagather, Assistant Secretary 1980 IR 1111 UOTATIOH OF docomebt kkvizmkh redacted 0641630 e M < lU N N H H CONTENTS Abstract............................................................................................................... Introduction.................................................................................................... Acknowledgments.............................................................................................. Review of medical aspects.............................................................................. Mineralogy and petrology................................................................................ Definitions............................................................................................... ` Nomenclature Inconsistencies......................................................... . Sampling and evaluation of fibrous dusts........................................ Mineral fiber identification problems and some examples............ Discussion of minerals which may occur in fibrous fora............. Discussion with predictions of ore desposits which may contain fibrous minerals............ ................................................................. Possible fibrous mineral occurrences in different rock types... Basle Igneous rocks.................. ................................................. Medium-basic Igneous rocks.......................................................... Sedimentary rocks........................................................................ . Metamorphlc rocks............................. ............................................ Summary and conclusions.............................. .................................................. .. References........ ........................................................................................................... Appendix I--Minerals that may occur in fibrous habits, their synonyms, ' and rock types generally expected to conealn minerals of a fibrous nature............ ................. ........... ......................... . Appendix II--Mining operations and/or localities, by consaodities, where "fibrous" minerals may possibly be found............./............... .. 10 12 IS 23 0641631 ASBESTIFORM AND/OR FIBROUS MINERALS IN MINES, MILLS, AND QUARRIES *>y' Walter Bank 1 ABSTRACT One theory of mineral-fiber-induced lung damage holda that the shape and size of the responsible inorganic materials are significant factors. Asbestifonn minerals, fibrous minerals, or elongated cleavage fragments, irrespec tive of the mineral name applied or definitions employed stay, therefore, become significant in a health evaluation of airborne dust. Many minerals in ore deposits and quarries exist in variable habits, including the fibrous shape. Names of such minerals vary, depending on locality, availability of analytical equipment and personnel, traditional usage, and other factors. Because of these factors workers in the mining and associated industries unknowingly may be exposed to asbestlform or fibrous minerals. Appendix I lists many minerals that occur in asbestlform or fibrous habits or which tend to cleave into elongated fragments. Appendix IX lists some selected mines, arranged by comnoditles and scattered throughout the conter minous United States, where fibrous minerals may be found. Actual mine vis itations have confirmed die presence of such fibrous minerals. INTRODUCTION Experiments on animals and human pathology indicate that the size and shape factors of lnorganle substances are significant in the etiology of asbestools, other pneumoconioses, and various cancers. Many miners, mineral processors and quarry workers may unknowingly be exposed to asbestlform and/or fibrous minerals which are hazardous to their health. Industrial minerals, sold directly in the form of consumer products, may also constitute health risks to the consuaier. This report discusses mineral assemblages found in ore deposits and quarries, cites potential hazardous minerals, and predicts where fibrous min eral health hazards might exist. `Mining engineer, Industrial Health Branch, Technical Support, Denver, Colo. 441631 ASBESTIFORM AND/OR FIBROUS MINERALS IN MINES, MILLS, AND QUARRIES by Walter Bank 1 ABSTRACT On* theory of minara1-fiber-induced lung damage holds that th shape and size of the responsible Inorganic materials are significant factors. Asbestlform minerals, fibrous minerals, or elongated cleavage fragments, Irrespec tive of die mineral name applied or definitions employed may, therefore, become significant in a health evaluation of airborne dust. Many minerals In ore deposits and quarries exist In variable habits, including the fibrous shape. Names of such minerals vary, depending on locality, availability of analytical equipment and personnel, traditional usage, and other factors. Because of these factors workers in the mining end associated industries unknowingly may be exposed to asbestiform or fibrous minerals. Appendix I lists many minerals that occur In asbestiform or fibrous habits or which tend to cleave Into elongated fragments. Appendix II lists some selected mines, arranged by comnodities and scattered throughout the centerminous United States, where fibrous minerals may be found. Actual mine vis itations have confirmed the presence of such fibrous minerals. INTRODUCTION Experiments on animals and human pathology Indicate that the size and shape factors of Inorganic substances are significant in the etiology of asbestosis, other pneumoconioses, and various cancers. Many miners, mineral processors and quarry workers may unknowingly be exposed to asbestiform and/or fibrous minerals which are hazardous to their health. Industrial minerals, sold directly in the form of consumer products, may also constitute health risks to the consumer. This report discusses mineral assemblages found In ore deposits and quarrlas, cites potential hazardous minerals, and predicts where fibrous min eral health hazards might exist. `Mining engineer, Industrial Health Branch, Technical Support, Denver, Colo. 0641632 2 ACKNOWLEDGMENTS The author owes many thanks to Dr. Arthur M. Langer, mineralogist at the Environmental Science Laboratory of the Mount Sinai School of Medicine, New York City, for his invaluable discussions and reviews of portions of this report. REVIEW OF MEDICAL ASPECTS Mining and milling Industrial-type asbestos has produced both the pneumoconiosis ealled asbestosls and neoplasm specifically aetributad to asbestos; yet after more than 40 years of published research on biological aspects, many questions remain, particulary the dose-disease response relation ship with respect to cancers. At an international conference on the biolo gical effects of Ingested asbestos held in Durham, North Caroline, in Novem ber 1973, Dr. Paul F. Holt of Beading University, England, alluded to some of the uncertainties with the question, "Does asbestos matter, or doesn't it?"(l; The term asbestos is ambiguous, because it includes many natural inorganic minerals, all with an asbestiform habit, diet differ from each other in chemical composition, particle-size ranges, morphology, and probably bio logical effects. The definition of and discussion of die term asbestos will be reserved for the mineralogy and petrology section of this report. The pneumoconiosis called asbestosls is characterised by,among other things,the presence of an abnormally high quantity of ferruginous bodies or "asbestos" bodies in the lungs. These are generally golden-brown ferro-coated formations, usually symmetrical and segmented with clubbed ends,3 to 5 microns in cross section and 20 to 30 microns in lengdi. The core consists of a fiber which may or may not be asbestos (16). The ferruginous bodies, are in fart, nonspecific. The core fibers may be synthetic materials such as fibrous glass or other inorganic materials. Recent animal experimental work, as stated in the literature, demon strated that fibrous glass, palygorskite, namallta (brueite), pectolita as well as asbestos, caused fibrosis and/or abdominal tumors and mesotheliomas. Some experimenters stressed the importance of particle-size ranges and shapes, and were drawn to the conclusion that the pathologic reaction to asbestos, fibrous glass and other fibrous materials seems primarily related to the shape, size and durability, rather than to other parameters, such as surface properties and chemical composition(34), (22), (9), (6), (25), (36), (7), (23), (38). Some investigators believe that the longer fibers (longer than 5 micro meters) are store hazardous as demonstrated by the ferruginous bodies des cribed above, which are found in connection with esbestosia and soma cancers; other Investigators believe that the shorter fibers are significantly hazar dous with respect to mesotheliomas (17). The shorter fibers tend to reach the smsothelial linings. Also,smaller fibers tend to migrate to other organs once inhaled and/or Ingested. `Underlined numbers in parentheses refer to items in the list of references preceding the appendixes. *4l633 3 Welsh investigators believe chat the fibrous zeolite, erionite, 1 responsible for an epidemic of mesothelioma observed in the Turkish village of Karians. This belief was expressed at the meeting of the Society for Occupational and Environmental Health, held December 4-7, 1977, in Washington, D.C. The work of Stanton (34) suggests that any durable fiber within a given range of length and diameter may be carcinogenic. The discussion in die previous paragraphs indicates that a quandry exists in medical knowledge concerning "asbestos1' exposure and resulting disease. Tumors have been produced when various fibrous minerals and inor ganic fibers have been injected into the pleural cavities of experimental animals. These tumors occur when the fibers are longer chan eight micrometers and less than 0.25 micrometer in diasMtar. According to soma authorities, shorter fibers do not produce such tumors; other authorities disagree. Shorter fibers would be important contributors to cancer induction if a biochemical mechanism for cancer were involved. Other animal experiments with fibrous dusts have also resulted in flbrotle lung reactions. When the fibers have been carefully prepared and characterised, the longer fibers are considered responsible for the flbrotle reactions when the animals are exposed through inhalation or intra-tracheal instillation. Because a method of transport of fibers inhaled by humans from the airways of the lung into the pleura is not known, these animal experiments are often discounted for interpreting human data. However, mesotheliomas occur in humans who are associated with at least three of the cosmerclal asbestos types, namely chxysotlle, amosite, and crocldollte. No cases of mesothelioma have been reported among Finnish miners who were exposed only to anthophylllte asbestos, but an exeass of lung cancer exists. Aside from shape and size factors, biochemical mechanisms for cancer induction merit serious consideration. A paper sunmarlzing possible bio chemical mechanisms has been given by longer and Wolff (17). Because of the unknown mechanism for cancer induction, the properties of fibrous minerals that are important to disease production are not known. With the present state of our knowledge, it is not possible to < a particle either physically or chemically and be able to say whether it may or may not be biologically active. Indeed, the several different diseases resulting from asbestos exposure may result from different particle properties. But among all the possibilities of health hazards causes, the Stanton and Wrench (34) work currently appears to be most acceptable as a consensus opinion. MINERALOGY AND PETROLOGY Definitions As stated earlier, the term "asbestos" is ambiguous. Asbestos is a generic term for a variety of hydrated silicate minerals which have one common / f 634 4 attribute, namely the ability to ba separated into relatively soft, silky fibers. Minerals which fit the above description are described as osbestl-* form minerals (32), whereas the term asbestos is generally applied to the coamercial product. Recently, mineralogists have been applying more refined definitions to such terms as asbestos, fibers and their associated terminology (30), (3). Comcreial production and applications of asbestos fibers are considered usually to be the significant source of asbestos fibers entering the environ ment, but this may be a misleading over-simplification. The thesis of this report is that, potentially, many vorkars in the mining and associated indus tries unknowingly may ba exposed to asbastifoxm or fibrous minerals which occur as gangue minerals. Cralley at al (5) report over 100 different minerals with some degree of fibrous structure; their examples include, and rightly so, minerals other than hydrated silicates. These minerals may be found in ore daposits, rock quarries or soils not normally associated with commercial asbestos, and may become airborne by natural atmospheric conditions (32) or by conventional mining and milling operations. Nomenclature Inconsistencies A mineral, by definition, is a natural inorganic substance with a given chemical composition and with a given atomic structure which is expressed by its crystalline form and other physical properties. Presumably, it is also homogeneous. This definition of a mineral is loosely applied and has many excaptions. As more sophisticated analytical equipment has been employed, many so-called minerals have turned out to he mixtures of intergrown minerals; the old nines ,, however, often are retained. Serpentine, for example, can be a single mineral or mixture of several minerals, but the term serpentine is still in common usage...as a mineral group name and as a rock noma (serpentinite generally is used as the rock nan). This looee practice is particularly true when exact mineral identification is economically unwarranted or difficult to obtain. Soma diversely named minerals from different localities have turned out to ba variations of the seme mineral, with the result that the same crystal line matarlal may have two or more names. When so identified, one nasw is given priority, but the other names are retained also -- partlculary when localities or personalities are involved. For example, williamslte, the gem serpentine material now is identlfiad as antlgorlte; bowenlte and picrollta also turn out to be antlgorlte; and yet all names are employed in the mineral literature. The chemical nature of the minerals may become quite complex, with different elements substituting for each other in varying ratloe. When only a few elements are involved, one may have family mineral groups with end members carrying the names. For example, actinolite is the iron-rich member of the tremolite-actinolite series, with a division point established at / k U1 0641435 S 10 percent iron, according to one authority; whereas another authority restricts the naae actinolite to members with the iron content between 10 and 90 mol percent, and applies the name ferro-actlnolite to the iron-rich end of the series. Other authorities have their own ranges and nomenclature for mineral families. Also, the variable nature of amphlboles, pyroxenes and chlorites (the common "ferro-magnesians") makes it necessary to classify a particular sample as '"most closely resembling" a specific mineral species or variety. And it must be noted that conclusive identification is very diffi cult, often requiring electron microscopy, X-ray and/or aleetron diffraction, and other ultra-sophisticated analytical methods. Adjectival prefixes may be used with mineral names, two examples being soda-asbestos iron-rich tourmaline; or more specific names such as eckermanite or schorl may be used interchangeably for those two minerals respectively* Sometimes economic or technologic conditions determine the mineral's name; for example, if the minerals of the cummingtonite-grunerite series are of economic value as asbestos, the names amoslte or montaslte are used, depending on the mineral deposit's location or the mining company working the deposit. Some mineral names are used both as a group name and as a specific mineral name; montmorillonite is such an example, and because of the confusion this engenders, attempts are made to apply the name smectite as the group name. Currently, mineral names of the montmorillonite group are used without much agreement in nomenclature. Rock names compound the confusion caused by mineral nomenclature. By definition, a rock consists of one or more minerals, and makes up a struc tural unit of the earth's crust. It generally has a sufficiently definite mineral composition and physical character so chat it can be distinguished from its neighbors -- but not always; gradations in composition and alteration effects are pronounced on a local level. For example, pyroxene is a "family name for numerous ferro-magneslum minerals; pyroxanite is the nsma applied to the rock unit when it is composed predominantly of pyroxene minerals and/or their alteration products, that is. serpentine, chrysotile, etc. Amphibole likewise is a "family" name for numerous ocher ferro-magnesium minerals; amphibolite is the name applied to the rock unit when it is composed predominantly of amphibole minerals. _ For the most part, ore deposits are freaks of nature. They represent concentrations of mineral substances chat can be mined at a profit. Such deposits may occur in Igneous, sedimentary or metamorphic rocks, which are the three major classifications of rock systems. Asbestiform or fibrous minerals also are found in the major types of rocks and are associated with ore deposits. These asbestos minerals may be obvious to the eye and may even be mined for their value, or their presence may be recognised only by trained personnel or even be entirely overlooked. / 0441634 6 Sampling and Evaluation of Fibrous Dusts At this point, a digression as to industrial hygiene sampling techniques and sample evaluation is in order. For asbestos-hazard evaluation. Mine Safety and Health Administration (MSHA) personnel employ the air sampling and counting method established by the U.S. Public Health Service (2). This involves collecting airborne dust on a cellulose ester membrane (Millipore) filter at a known air flow rate, preparing microscope slides of the sample, and counting fibers with phase contrast microscope optics at approximately 400-450 diameter magnification. Only particles with a 3 to 1 length-co-width ratio or greater, and longer than five micrometers in length are counted; shorter particles are not counted although they may be present in large numbers. Presumably, fibers with a width as small as two-tenths micrometer can be detected by this method; thinner fibers are present which can be seen with the electron microscope. Thus, our counting technique, although standarized, is only an index of the total exposure. It must also be noted that different Government agencies have different standards for health-hazard evaluation; the Food and Drug Administration states that there are many asbestos minerals but only six are of comerclal importance (13)3 and limits their presence in a product to a specific percentage of its composition; the Occupational Safety and Health Administration (OSHA) and MSHA enforce standards for as bestos based on time-weighted averages of airborne fibers greater than five micrometers in length per milliliter of air; and the Environmental Protection Agency has other standards or guidelines. The MSHA standard, including the minerals specified as asbestos, is published in Title 30, Code of Federal Regulations, Part 55.5-l(b). Airborne dust does not necessarily have the same mineral composition percentages as the parent rock. The fine, fibrous fraction may comprise a greater proportion of the airborne dust than the parent rock. In addition, the nature of fibrous minerals is such that small amounts of fibrous minerals may not be detected by conventional analytical methods - yet when the material is crushed and becomes airborne, significant amounts of fibers or elongated cleavage fragments are observed on the filters. For example. Spell and Lelneweber (32) cite and illustrate a sample of pure serpentine considered to be of nonfibroua composition based on petrographic examination; yet this "museum grade" translucent serpentine yielded 20 percent fibers under the electron microscope. Mineral Fiber Identification Problems and Some Examples Fibrous minerals collected on filters are often difficult to identify. For example, chrysotlle and its host rock "serpentine" yield Identical X-ray diffraction patterns but can be distinguished from each other by optical microscopy or electron microscopy. .Under the electron microscope, some "granular" or massive serpentine probably will turn out to be fibrous in part, as in the Spell and Lelneweber (32) example cited above. JA deposit of richterite, one of the amphlbole minerals not usually listed as a commercial asbestos, reportedly is contained in the Diablo Asbestos Deposit near Van Horn, Texas. This deposit Is suitable for strip mining. P The energy dispersive X-ray analysis (EDXRA) end ehe selected sres electron diffraction (SAD) methods used in conjunction with the transmission and scanning electron microscope are useful tools for identifying fine fibers, but have limitations such as not being readily available. Visually insignificant amounts of fibrous material are found with vermieulites from the Carollnas, yet reportedly significant amounts of fibrous material are found in airborne dust samples. The important vermiculite ore deposit at Libby, Montana contains easily recognisable fibrous tremollte in hand specimens, and airborne dust samples under the phase contrast microscope show numerous fibers which are inferred to be trasiolite, but electron mic roscope pictures prepared by Mt. Sinai Hospital personnel demonstrate that chrysotile fibers also are definitely present (personal communication). Recently a published paper describes vermiculite altering to chrysotile (19). Chrysotile is one of the few fibers which usually can be identified under the transmission electron microscope when finely divided. It is important to speclfly the method of analysis when stating analy tical results. MeCrone and Stewart (18) eite a talc analysis as follows: "1. X-ray diffraction shows no chrysotile or amphlboles. 2. A phase-contrast method (similar to the NIOSH procedure to determine the number of fibers per milliliter of air) shows 1,500 fibers greater than 5um/mr of sample. 3. Ihe scanning electron microscope with energy dispersive X-ray analyzer shows about 104 fibers/liter suspected of being amphibole asbestos. 4. Dispersion staining shows 150 anthophyllite fibers/gram of sample. 5. Transmission electron microscopy shows 5 x 10^ anthophyllite fibers/ liter of sample/* Fibrous minerals generally are present in talc deposits, but until recently have not been suspeeted as a public health problem in the general population. Now the importance of these fibers has been recognized for calc of cosmetic grade, and analytical X-ray and electron diffraction methods have been developed to determine the quantity of fibers down to a quarter or a half of a percent (33)r (30). Reportedly, this applies to tremollte and ocher asbestifoxm minerals. Many minerals adopt different habits or shapes in nature. They may be piety in one deposit, equant crystals in another deposit, or acleular (needle-like) or threadlike in yet another. In short, most asbestlform * minerals have their different shaped counterparts with the same chemical composition. Finally, as indicated earlier, a mineral substance may be assigned any one of several names, depending on the degree of completeness of analysis and upon the analyst's definition of terms. 8-- <S4i<S38 Discussion of Minerals Which Mav Occur In Fibrous Fora Mining literature contains many references where minerals that may occur in fibrous form or cleave into elongated fragments are associated with ore deposits or quarried rock. Certain industrial mineral or ore deposits characteristically contain asbestiform minerals as an impurity or, as in the case of some talcs, as a desirable ingredient (for example, as a paint extender). An admittedly incomplete list of minerals that may occur in fibrous habits and which occur in rocks or ore deposits together with some synonyms and rock terms that lamediately imply the presence of fibrous minerals is tabulated in appendix 1. Appendix I requires further explanation. Certain rock types, particularly where "alteration" has occurred, tend to have minerals which easily replace others of a somewhat similar chemical composition. If ocher chemical elements have been introduced into the rock during the alteration process, still other minerals will be formed. Alteration effects vary in degree from "fresh" rocks to completely altered material. The size of die new-formed minerals may range from relatively huge crystals to grains or fibers recognizable only under the high magnification of the electron microscope. Discussion With Predictions of Ore Deposits Which Mav Contain Fibrous Minerals As mentioned earlier, the three types of rocks (Igneous, sedimentary, and metamorphie) all carry ore deposits. Hocks of each type, when altered, have certain characteristics in common - sometimes. And these characteristics include the formation and presence of minerals which might have the asbesti form or fibrous habit. Knowing the generalized mineral associations that may occur in these ore-containing rocks, it is possible to infer the presence of certain minerals chat may or may not occur in fibrous habit in the size range of hygienic interest. But whether the mineral actually is fibrous in a particular deposit can be determined only by direct observation or careful analysis; only occasionally can the fibrous habit be definitely predicted. For example, most talc deposits contain one or more fibrous minerals or minerals which cleave into elongated fragments, but some deposits are relative ly fiber-free. Another example, ultrabaale Igneous rocks alter easily, and a reasonably certain prediction can be made that serpentinires will be found that carry some fibrous minerals. To demonstrate the thesis that many workers in the mining industry may be exposed to asbestiform or fibrous minerals, a list of some well-known mines, or mining areas, was prepared; this listing, by commodity, and noted as appendix II, was selected largely from a recently published book entitled. Ore Deposits of the United States. 1933-1967 (26). This publication was selected because of its timeliness and accessibility; and specific pages are referenced for localities of mines or commodities where minerals are noted which commonly occur in the asbestiform or fibrous habit. These examples were selected specifically to demonstrate the wide geographic range in which ore deposits carrying fibrous or asbestiform minerals may occur. To amplify the examples from this publication, other specific references also are cited in appendix II. 441<S39 9 Possible Fibrous Mineral Occurrences In Different Rock Types Besle Igneous Rocks Basic igneous rocks, meaning igneous rocks which are relatively low in silica, usually contain "ferro-magnesium" minerals. Such rocks alter easily, with the minerals changing to other ferro-magnesians. In this process, many of the minerals formed may be of fibrous character. Serpentines or serpentinites are a comoon alteration product with their usual complement of fibrous minerals. Also, zeolite minerals and their associated minerals often are found in basic rocks. Medium-Basic Igneous Rocks Medium-basic igneous rocks also carry ferro-magnesium minerals in the formof amphiboles or pyroxenes. When these rocks are altered, as occurs commonly when ore minerals are introduced, for example, as in the so-called porphyry coppers of die Southwest, these ferro-magnesium minerals may alter to minerals with a fibrous habit. Sedimentary Rocks Among sedimentary rocks, soma clay minerals such as attapulgite, palygorskite, meerschaum, etc., are normally fibrous; or they may become so under very low-grade metamorphic conditions. Some soils are known to contain fine fibrous palygorsklte of nondetrltal origin (31). In limestones and dolomites of the Northwest U.S.A., certain areas, such as the Metaline Falls country, Washington, have been mineralized and yield lead ores; fibrous palygorsklte or "mountain leather" which is classed as a clay mineral is a common gangue constituent. Tremrlite, also, has been described (oral comnunieation, John Currie, MSHA) as a component of these rocks. Reportedly, the Abril Zinc Mine (Cochise County, Arizona) has asbestos in the Permian limestone (35). Sometimes sedimentary beds of pyroclastic origin (volcanic ashes, etc.) yield considerable amounts of zeolite aiinerals (20), (21). Metamorphic Rocks When Igneous or sedimentary rocks are metamorphosed; that is, altered significantly, minerals of a fibrous character can develop. Basic Igneous rocks become decomposed dunites or kimberlites, or altered pyroxenites, grading over into serpentinites and amphibolites to "greenstones," or even to vermiculite-biotite-tremollte assemblages of minerals; in turn these often develop into mineral assemblages that also may contain other fibrous minerals. Limestones and dolomites are altered to "tactites" or fbrro-magnesian assemblages under certain conditions, with later alteration to minerals of fibrous habits; or they may altar in part or completely to serpentinites with fibrous assemblages as in the asbestos deposits of Arizona (35). Limestones or dolomites may be altered to tale deposits in which occur piety and/or fibrous smphlboles plus, sometimes, chrysotlle. 0441640 10 Soma of Che so-called "marble" or verd antique, an ornamental stone used as facing material. Is actually a serpentine or a serpentine-calcite complex. Such rocks may contain significant amounts of fibrous minerals. Other quarries developed for construction materials in rocks, such as limestones, dolomites, serpencinites, crap rock, and tuffs.may carry fibrous or cleavabie minerals, such as cremolite, chrysotile, or zeolite minerals and associates. One as bestos open-pit mine In California sold its serpentinice waste rock for road bed material; and some parking lots, or equivalent, are filled with serpentinite waste rock from the old chroma mines in the Pennsylvanla-Maryland area. Homes take, a gold mine with a country rock consisting largely of euaningtonite-grunerite, uses some of its waste rock locally to fill in-low spots or in parking areas. Quarried serpentinite has been used as road-bed and drive way gravel in the Washington, O.C., area (29). Shales and siltstones alter to schists, gneisses, and quartzites; when admixed with limestones or dolomites, talc deposits may form. Sillimanite schists, pyrophyllite schists, and other similar metamorphlc rocks containing fibrous minerals are derived, generally, from shales. SUMMARY AND CONCLUSIONS The pneumoconiosis called asbestosis and neoplasms such as lung cancer, gastxo-intestinal cancer, and mesothelioma, are attributed to asbestos as a causal agent, but the exact mechanism of the insult is not known. Hence it is not possible to examine a particle either physically or chemically and be able to say whether it may or may not be biologically active. Among the various theories proposed, one theory is assuming strong support; it holds that the shape and size and durability of inorganic fibers are important factors. Therefore, fibrous minerals or elongated grains or elongated cleavage fragments, irrespective of the composition and other physical characteristics, may possess significant potential hazard in airborne dust. Many minerals in ore deposits and quarries exist in varied habits, including the fibrous shape, or break into elongated fragments. The names of such minerals may vary, depending upon identification requirements, the availability of analytical equipment end personnel, and local terminology The term asbestos is indefinite. If we think more in terms of "asbestlform" or fibrous or elongeted fragments, then many minerals become suspect. A list of potential fibrous minerals and rocks carrying fibrous minerals is appended. Many of these minerals, if fibrous, may go unnoticed to the average observer. A literature search revealed that many ore deposits contain gangue minerals which may occur in a fibrous form. A list of mines or mining areas, arranged by coanodity and selected to expresss the wide, geographical range of deposits, is appended together with references to document these occurren ces of suspect minerals. This list represents selected mine examples only, and is by no means to be considered comprehensive. Also one must recognize that the minerals cited may or may not be fibrous* In many cases, only an *4t64i 11 analysis by an alactron aieroacopc will confirm whachar asbaaclform or fibrous minarals ara praaane in cha airborne dust. Many uncertaineias exist concerning the mineral terminology and many medical differences of opinion are expressed in the field of asbestos or mineral fiber pathology. MSHA and the National Institute for Occupational Safety and Health (NI05H) have cooperatively undertaken several studies to further define the hazards of fibrous mineral exposures. Although not complete, these studies involve tale, wollaseonite and attapulgite mining as well as the mining of recognized asbestos minerals. NIOSH also is attempting to simplify fiber-count evaluation (11). It is important that persona exposed to fibrous minerals understand the potential for disease, and therefore, the Mine Safety and Health Administration (MSHA) is providing this Information to the mining industry. MSHA inspectors are actively attempting to identify all probable exposures to fibrous minerals and have collected airborne dust samples, following the NIOSH standardised procedures (2), to evaluate the hazard and suggest remedial action. Mine operators should be alert to the possibility of Illness that may be associated with any fibrous mineral. Those operators whose employees are exposed to recognized asbestos minerals should conduct air sampling programs and taka suitable action to assure that the employees are not exposed to asbestos dust exceeding applicable standards. When employees are exposed to other fibrous minerals, the operators should also taka air samples to evalu ate exposures using the same techniques as for asbestos. Employees should also be fully Informed regarding their exposures and the potential for disease as well as the necessary controls and actions they may take to prevent unnecessary exposure. .sag" 0641642 REFERENCES 1. American Chemical Society. Asbestos Health Question Perplexes Experts. Chemical and Engineering News, Dec. 10, 1973, pp. 18-19. 2. Bayer, S. G., T. H. Brown, and R. D. Zumwalde. NIOSH Document TR-84, Cincinnati, OH, 1975, 84 pp. 3. Campbell, V. J., R. L. Blake, L. L. Brown, E. E. Cather, and J. J. Sjoberg. Selected Silicate Minerals and Their Asbestifom Varieties. BuMines 1C 8751, 1977, 56 pp. 4. Chidester, A. H., and A. F. Shride. Asbestos in the United States. USGS Mineral Investigations Resources Map MR-17, 1962. 5. Cralley, Lewis J., Robert G. Keenan, Jeremiah R. Lynch, and William S. Lainhart. Source and Identification of Respirable Fibers. AmericanIndustrial Hygiene Association Journal, v. 29, March-Aprll 1968, pp. 129-135. 6. Davis, J. M. G. The Flbrogenic Effects of Mineral Dusts Injected Into the Pleural Cavities of Mice. Br. J. Exper. Pathol., v. 53, 1972, pp. 190-201. 7. Dement, John M. Environmental Aspects of Fibrous Glass Production and Utilization. Environmental Research, v. 9, No. 3, June 1975, pp. 295-312. 8. Dement, John M., Ralph D. Zumwalde, and Kenneth M* Wallingford. I Discussion of Reference No. 14, pp. 345-352. 9. ' Dreger, Don. Do OSHA Regulations Affect Selection of Plastic? Machine Design, April 15, 1973, pp. 105-107. 10. Engel, A. (ed). New York Talcs, Their Geological Features, Mining, Milling and Uses. Mining Transactions v. 184, September 1949, pp. 345-348. 11. Eng. and Min. J. v. 179, January 1978, pp. 133. 12. Faust, George T., and Joseph J. Fahey. The Serpentine-Group Minerals. USGS Professional Paper 384-A, 1962, 92 pp. 13. Federal Register Announcements (38 FR 27076, 40 FR 11865, 41 FR 16932) related to the use of asbestos filters and talcs. Also found in 21 CFR Parts 121, 128,and 133. 14. Gillam, Dean, John M. Dement, Richard A. Lemon, Joseph K. Wagoner, Victor E. Archer, and Hector B. Blejer. Mortality Patterns Among Hard Rock Gold Miners Exposed to an Asbestos Mineral. Annals New York Acadmoy of Sciences, 1976, pp. 336-344. wm S*f*ty and Health Administration Informational Report 1111 ASBESIZFOBM and/or fibrous minerals ZB MINES, MILLS, AND QUARRIES bj Halter Bank 0641643 Page 12 Page 14 Page 24 Page 23 Item 14 Item 36 Item 24 BWATl Lemon should be Lemea 6. Verry should be G. Berry Reference 24 should be deleted In "Note" at bottom of page: Eastern Mesabl Iron Range county ahould be Eastern Mesabl Iron Range country 1<S44 U 15. Grim, Ralph E. Clay Mineralogy. MeGrav Hill Book Co., Inc. , Now York, ' 2d ad., 1968, 596 pp. 16. Groaa, Paul, Robert T. P. de Treville, Lewis J. Cralley, and J. M. G. Davis. Pulmonary Ferruginous Bodies. Arehieves of Pathology, v. 85, May 1968, pp. 539-546. 17. Langer, Arthur M., and Mary S. Wolff. Asbestos Carcinogenesis. Chapter 3 in the volume entitled Inorganic and Nutritional Aspects of Cancer, 1978, ed. by G. N. Schrauzer. Plenun Publishing Corp., New' York, pp. 29-55. 18. McCrone, Walter C., and I. M. Stewart. Asbestos. American Laboratory, v. 6, No. 4, April 1974, pp. 13-18. 19. Mifsud, Amparo, Vincent Pomes, and Jose A. Rausell-Colom. Natural. Alteration of Vermieulite to Chrysotlle. American Mineralogist, v. 62, Nos. 11-12, 1977, pp. 1225-1231. 20. Mumpton, Frederick A. First Reported Occurrence of Zeolites in Sedimen tary Rocks of Mexico. American Mineralogist, v. 58, Nos. 3-4, 1973, pp. 287-290. 21. Mumpton, Frederick A. (ed). Mineralogy and Geology of Natural Zeolites. Mlneralogical Society of America, v. 4, November 1977, XI + 233 pp. 22. Occupational Health and Safety Letter. New Study Demonstrates Mechanism of Asbestos Effects. January 8, 1973, pp. 5-6. 23. Occupational Health and Safety Letter. Non-asbestos Fibrous Dust Can Induce Tmnrs, as it has been Prc/eu for Asbestos. V. 4, No. 13, July 8, 1974, p. 1. 24. Pennington, James W. Mercury--A Materials Survey. BuMines 1C 7941, 1959, 92 pp. 25. Pott, F., 7. Huth, and K. H. Friedrichs. Tumorlgenlc Effects of Fibrous Dusts in Experimental Animals. Environmental Health Perspectives, v. 9, 1974, pp. 313-315. 26. Ridge, John D. (ed). Ore Deposits of the United States, 1933-1967. AIME, 2 v., New York, 1968, 1880 pp. 27. Roberts, Willard Lincoln, George Robert Rapp, Jr., and Julius Weber. Encyclopedia of Minerals. Van Nostrand Relnhold Co., 1974, 693 pp. 28. Rohl, A. N., and A. M. Langer. Internal Memorandum to Dr. X. J. Sellkoff, Mount Sinai School of Medicine, New York, entitled, Mineral Analysis of Cora Samples from the Green Springs Area, Virginia Vermieulite Deposit, dated July 1, 1977. / I 0*41643 14 29. Rohl, Arthur N., Arthur M. Linger, end 1. J. Selikoff. Environmental Asbeecos Pollution Releted to Use of Querried Serpentine Rock. ScienceJ v, 196, June 17, 1977, pp. 1319-1322. 30. Rohl, A. N., A. M. Linger, I. J.'Selikoff, A. Tordlni, R. Klimentidis, D. R. Bowes, end D. L. Skinner. Consumer Tilcums end Powders; Mineral end Chemlcil Chincterizitlon. Journil of Toxicology end Environmental Heelth, v. 2, 1976, pp. 255-284. 31. Singer, Arleh, end Keith Norrlsh. Pedogenic Palygorskite Occurrences in Australia. American Mineralogist, v. 59, Nos. 5-6, 1974, pp. 508-517. 32. Spell, S., and J. P. Leineweber. Asbestos Minerals in Modern Technology, Environmental Research, v. 2, No. 3, April 1969, pp. 166-208. 33. Stanley, Harold D., and Robert E. Norwood. The Detection and Identifi cation of Asbestos and Asbestlform Minerals in Talc. Presented at the Talc Symposium, Bureau of Mines-, Washington, D.C., May 1973. 34. Stanton, Mearl 7., and Constance Wrench. Mechanisms of Mesothelioma Induction with Asbestos and Fibrous Glass. Journal of the National Cancer Institute, v. 48, No. 3, March 1972, pp. 798-821. 35. Stewart, L. A. Chrysotile-Asbestos Deposits of Arlxona. BuMines IC 7706, January 1955, 124 pp. 36. Wagner, J. C., G. Verry, and V. Timbrell. Mesothelioma in Rats After Inoculation with Asbestos and Other Materials. Br. J. Cancer, v. 28, 1973, pp. 173-185. 37. Weiss, Benjamin, and Edward A. Boettner. Coraercial Talc and Talcosis. Archives Environmental Health, v. 14, January 1950, pp. 122-128. 38. Wright, G. W,, end M. Kuschner. The Influence of Varying Lengths of Glass and Asbestos Fibers on Tissue Response in Guinea Pigs. Inhaled Par ticles IV, ed. by W. H. Walton. Pergamon Press, Oxford and New York, 1977, pp. 455-473. 39. Wright, Lauren A. California Talcs. Mining Engineering, v. 187, January 1950, pp. 122-128. 0641646 15 APPENDIX I.--MINERALS THAT KAY OCCUR IN FIBROUS HABITS, THEIR SYNONYMS, AND ROCKS AND MINERAL SUITES GENERALLY EXPECTED TO CONTAIN MINERALS OF A FIBROUS HABIT. 1. Chrysotlle Specified as an asbestos by MSHA. 2. Aaosite Do. 3. Crocidolita Do. 4. Trentolie* asbestos Do. 5. Aetlnollte asbestos Do. 6. Anthophyllite asbestos Do. 7. Cuaningtonita An end member of the cunnington!tegrunerite series. Industrial forms of this mineral are called (2) amosite or (8) montaslta. 8. Montaslta See (2) and (7) above. 9. Grunerlte See (7) cunningtonite. 10. Rlebeekite The fibrous, commercial material is called (3) crocidolice. 11. Magnesioriebeckite 12. Amphlbole A family name for a goup of silicate minerals, many of which are asbesti- form or break into elongated cleavage fragments. Includes (2), (3), (4), (5), (6), (7), (8), (9), (10), (11), (13), (14), (15), (16), (17), (18), (19). (20), (21), (23). 13. Glaucophane 14. Shodusits A fibrous variety of glaucophane. 15. Riehterlta 16. Hexagonlte e A manganoan tremolite. 17. Tlrodlte 18. Nephrite jade Tremolite or aetlnollte, fine-grained, massive and felted in hand specimens which yields Jade-like material. / 441647 16 19. Byssolite An olive-green variety o fibrous amphiboles. 20. Sod* **bc*to* 21. Eckermanite 22. Pyroxene Also soda asbestos (20). Used as a family name for a goup of silicate minerals (which includes fibrous jadeite). Often alters to smphlboles or to serpentine minerals. 23. Orallee An alteration product of pyroxene minerals, generally a fibrous amphibole of undetermined composition. 24. Woliesconite A cannon rock-forming pyroxenold mineral. 25. BustealCe A pyroxenold mineral. 26. Peetollee A pyroxenold mineral often found with zeolites. 27. Zeolites end associated minerals (see 26) including: (21). 28. Hardenlta (see Aaer. Min., it 58 (1973), pp. 287-290) (20). 29. Cllnoptilolite A zeolite. 37. Uatrolite Do. 31. Mesolite Do. 32. Scoleclte 33. Ihompsonlte 34. Gonnerdite Do. Do. Do. 35. Edingtonlte 36. Stllblte 37. Eplstilblte 38. Okenite Do. Do. Do. A zeolite associate. 39. Ferrierlte A zeolite. 40. Rhodesite A zeolite relative. / 0441648 JS m 17 41. Gmelinita 42. Laumontlta 43. Erionite 44. Serpentine 45. Clino-chrysotile 46. Para-chrysotila 47. Ortho-chrysotila 48. Antigorita 49. Lizard!te 50. PieroIlea 51. Deveyllte 52. Gymnite 53. Wiliiamsite 54. Baatita 55. Baltlmorlta 56. Mataxlte 57. Bovenite 58. Falygorakita 59. Attapulglte 60. Sapiolica A zeolite. A zeolite* A zeolite suspected of being the cause of an epidemic of mesothelioma in a Turkish village. A catch-all name for the serpentina minerals; sea (1) chrysotile; (45) clino-chrysotile; (46) para-chrysotile; (47) ortho-chrysotila; (48) antigorita; (49) lizardita. See (44). Do. Do. Do. Do. A fibrous "serpentinaprobably fibrous antigorita (48). Often determined to be any one of various serpentina minerals. A form of deveylits (51). , A massive, translucent semi-precious variety of serpentina. Probably mainly lizardita (see 49). Probably mainly antigorita (48) and chrysotile (1). Antigorita (48). . A fibrous clay mineral (sea Grim, Clay Mineralogy. 2nd edition, o. 182) (i>. A fibrous clay mineral (see Grim, p. 181) (15). See Grim (15). / ..W... 18 61. Meerschaum 62. Heccorlta 63. Endelllte 64. Halloysice 65. Illlea 66. Varmicullte 67. Sarleica 68. Finite 69. GumbeliCe 70. Ihlc 71. Pyrophyllite 72. MlnnaeotalCa 73. Stilpnomelane 74. Brudta 75. Nemalite 76. Magnaslta 77. Hydromagnealca 78. Gypsum 79. Anhydrite 80. Aragonite 81. Caleita 82. Apatite 83. Phosphorite 84. Vlvlanita 85. Sillimanlte 86. Buchholxite / 0641649 See Grim (15). Do. Do. Do. A mica-like clay mineral. Do. Belongs to the mica group. Do. A fibrous mica. A fibrous iron-talc. V A magnesium hydoxide* The fibrous for of (74) bruclte. A fibrous variety of (85) sillimanlte. 87. Fibroiite .88 Tourmaline 89. Zoisite 90. Epidote 91. Limonite 92. Mountain leather 93. Mountain cork 94. Amianthus 95. Ferro-magnesium minerals 96. Basle rocks 97. Serpentinlta 98. Amphibolite 99. Pyroxenlte * 100. Perldotlte 64US0 19 A fibrous variety of (85) sillimanice - A catch-all name for hydrous iron oxides and iron hydroxides. A tough variety of asbestos occurring in thin, flexible sheets made of inter laced fibers; also fibrous minerals such as (60) sepiollte or (58) palygorskite. A white or grey variety of asbestos consisting of thick, interlaced fibers and resembling cork in texture and lightness. A synonym for asbestos. A term referring to iron- and magnesium- containing silicates; usually the smphiboles, the pyro xenes, the olivines, biotlte micas, and chlorites. Igneous rocks, often altered in part, consisting essentially of iron-, magnesium-, and/or calcium rich minerals, and relatively low in silica. A rock composed largely of serpentine minerals. A rock composed predominantly of amphlbole minerals. A rock composed predominantly of pyroxene minerals and/or their altera tion products, l.e., serpentine, chrysotlle, etc. A basic. Igneous rock composed largely of olivine, a mineral which alters easily to the serpentine minerals. r 20 0441651 101. Talc achiat 102. Pyrophyilite achiat 103. Steatite Am impure talc rock. 104. Soapatone A massive, fibrous talc rock. 105. Agalaatolite A soft, waxy mineral or rock compoaed largely of (68) pinite. 106. Marble, when Impure 107. Verd antique Called (106) marble in the trade, but actually an impure aerpentine or a serpentine-calclte rock. 108. Theraophyllite A aerpentine that exfoliates when heated. 109. Ophite A synonym for a mottled serpentinite. 110. Ophicaleite A serpentine marble 111. Ophiolite Do. In a volume entitled "Encyclopedia of Minerals" (27), devoted to descriptions and Illustrations of minerals mainly as micro-mounts, the following minerals were noted in fibrous form: 112. Aegerlne 113. Agardlte 114. Artinlte 115. Aurlchaleite 116. Barlandite 117. Blsmuthlnite 118. Boulangerite 119. Brannockite 120. Brochantlte 121. Cacoxenite 122. Carpholite 123. Connellite 124. Cyanocrlchite 125. Curite 126. Erythrite 127. Goechite 128. GulllemiCa 129. Honasslce 130. IanChinita 131. Janasonite 132. Johannaenita 133. Kaznasica 134. Lagrandlca 135. Llebechanlca 136. Linarite 137. Malachlca 138. Mlllarlta 139. Minatite 140. Mlxita 141. Olivanita 142. Pharoaeoliea 143. Pyrita 144. Rockbrldgaita 145. Schoaplta 146. Scholzlta 0 *41 <552 21 22 147. Samaeyita 143. Stibnita 149. Strunzlte 150. Tyrollta 151. Uranophana 152. Hakabayaahlllta 0 6& / l 0641654 23 APPENDIX II.MINING OPERATIONS AND/OR LOCALITIES, BY COMMODITIES, WHERE "FIBROUS" MINERALS MAY POSSIBLY BE FOUND Unless otherwise specified, the pages listed refer to one or wore of the following: Chrysotile, amoslte, crocidolite, anthophyllite, tressolite, and actinolite. Page numbers refer to reference (26). See text, page--. Iron (26) 1. Cornwall Mino, PA, pp# 81*85 Refers also to zeolites, serpentine, and byssolite. (26) 2. Grace Mine, PA, pp. 110, 117-118 Refers also to serpentine and talc. (26) 3. Mesabi Iron Range, MI, pp. 525 and 528 Refers also to stllpnomelane, mixmesotalte, euuningtonite, and anphiboles. (26) 4. Iron Mountain, MO, p. 299 Refers also to amphiboles. (26) 5. Eagle Mountain Deposit, CA, Refers also to serpentines. pp. 1604-1605 CoPPer (26) 6. Ducktown District, IN, pp. 162-163, 222 Refers also to anphiboles, talc, and asbestos. (26) 7. Copper King Mine, CO, p. 574 Refers also to eunaingtonite. (26) 8. Christmas Mine,'Banner District, AZ*, p. 1204 Refers also to serpentine. (26) 9i -Mountain City Copper Mine, Refers also to uralitlzed gabbro. NV, p. 1080 Lead-Zinc (26) 10. Balmat-Edwards District, NY, pp. 13, 39, 41 Refers also to talc and serpentine. (26) 11. Van Stone Area, Stevens Co., HA, pp. 1515-1317 Refers also to brudtic fiber, palygorskite., and talc. / 0641695 24 - -- (26) 12. Cour-d'Alone District, IS* p. 1429 Refers to grunarlt* needles. (26) 13. New Idria Group* CA, Refers also to serpentine and pp. 1628-1630* 1646-1647 - asbestos. (24) 14. New Alaaden Mine* Sent* Clara County* CA Refers to serpentine. Chremlt* (26) 15. Mistake Mina* CA* pp. 1648*1649 Refers also to asbestos and serpentina. (12) 16. Low's Pit (State Line Pita)* PA Refers to williaaaite. (12) 17. Woods Chroma Mine Lancaster County* PA Refers to dino-chrysotlla* and deweylite (stevwnsita). Gold (26) 18. Hooestaka Mine, SD* p. 1437 Sea also Denver Technical Support Center memo dated 12/4/72. Refers to cummingtonita schist. Tungsten (26) 19. Bishop Thngsten District CA* p. 1549 Refers also to talc* vollastonlta and peetolita. Bar* 'darths (26) 20. Mountain Pass, CA* p. 1528 Aabesco* (26) 21. Clear Creek'(Mew Idria) CA, pp. 1628-1630, 16471648 (26) 22. Franklin-Somerset Area, MA* p. 137 Refers also to serpentine and asbestos . Refers also to serpentine'and asbestos. (4) 23. Webster and Sprue* Pine, NC* (vicinity) (35) (24) 24. Arizona, near Glob* Refers to serpentina. (12) (4) 23. Bar* Hill* tru, MD 0641654 25 (12) 26. Staten Island, NY Refers to serpentine. Magnesite (26) 27. Magnesite-brucita deposit Refers also eo calc, bruclte and Gabbs, NV, pp. 1617-1618. serpentine. (37) (10) 28. Gouverneur, NY vicinity Refers also co calc and serpentine. (37) (39) 29. Barstow, CA vicinity Veralculita Refers also to calc and steatite. 30. Libby MI vicinity 31. North & South Carolina depotits. (28) 32. Groan Springs, Charlottes- Refers also to amphibolites. villa, VA, deposit Crushed Stone (29) 33. Rockville Quarry, Rockville, MD Refers also to serpentine tale, and deveylita. ( ) See References NOTE: Since this report was begun, mineral fibers were confirmed to exist at (1) the Eastern Mesabl Iron Range county; (The Reserve Mining Company tailings disposal problem); (2) the Romascake Mine where a health hazard exists (14) (8); and (3) at Che Mountain Pass, rare-earCh deposit. In addition, questions have arisen re: (4) the wollaseonlte deposits of New York; (5) the attapulgita deposits of Georgia; (6) the Rockville Quarry (serpentina) near Washington, D. C.; and (7) Green Springs vermieulite deposits, VA. UA. GOVERNMENT PRINTING OFFICE: 1900403-10334 / t|9l2S