Document g21ve8RqMV4yMkD8d9DBmRVQN

FILE NAME Talc TALC DATE 0000 DOC TALC047 DOCUMENT DESCRIPTION Book Excerpt - Asbestosform Impurities in Commercial Talcum Powders PTERONITES AMERICANA of the shale unit produced ie relationship to the enclosing aminations enclosing REFERENCES a | 900 Carboniferous invertebrates 7 arvey v 6 pt 2 187 p ; 1951 The Pennsylvanian Mill ne in Pennsylvania Pa Geol Sur ' 36 p * compac 1963 Estimation of the hale from distorted brachiopod *. ed Per v 33 p 796-798 he 1866 Carbonformation und Dyas >: Kais deutsche Akad Naturfor_ . Nova Acta Leopoldina Dresden 915 Fauna of the Wewoka For- ahoma U.S. Geol Survey Bull 1837 A sketch of the geological king County accompanying an ziogue of Carboniferous fossils .dge Ohio Denison Univ Sci 2. p 5-70 2 Remarks on the Pinnidze 4 Proc v 25 p 335-346 Form function and Treation Treation Invertebrate Paleon- Moore ed Univ Kansas Press 129-205 395 date of imprint 1394 : Missouri v , pt 2 266 p 2. The fossils of the Conemaugh Ohio in D. D. Condie Ohio ull 17 p 261-326 57 Remarks on Prof. Geinitz's ; the upper Paleozoic rocks and eastern Nebraska Amer Jour p 170-187 282-233 327-339 eport on the paleontology of a with some remarks on the tacks of that 42d Cong- 2. 83-239 district in F. B. 1st sess House report on some of the inverte the Waverly Group and Coal 10 Ohio Geol Survey v 2 pt , 1922 Poctsville fauna of l Survey Buil 25 312 p 11. The Pennsylvanian fauna V. R. Jillison Ky Geol Sur 295-348 nd G. C. SWALLOW 1818 De- * fossils from the Coal Ma- - * and Kansas St. Louis Acad - 1. p 193-227 = 1970 Relation of shell form to the Bivalvia Mollusca Geol em 175. 196 p 7 = - I Description of fossil Gec Jurvey v 3 p 69 154- ASBESTOSFORM IMPURITIES IN COMMERCIAL TALCUM POWDERS David W. Snider Dan E. Pfeiffer and Joseph J. Mancuso Department of Geology Bowling Green State University Bowling Green Obio 43403 ABSTRACT Eighteen commercial talcum powders were examined by ray diffraction and the petrographic microscope to determine the amount and o--f asbestosform mineral impurities which were fibrous serpentine tremolite actinolite and an- thophyllite and which varied in amount from + percent to +6 percent PURPOSE AND SCOPE As part of a major study undertaken to mine the possible relationship of asosform mineral impurities in talcum powders to incidences of cancer in gerbils I. I. Oster 1971 personal com- munication various commercial talcum powders were examined for the type and amount of impurities contained An initial study by Merliss 1971 implied that coated rice gave rise to stomach cancer citing the asbestosform impurities in -:i as the carcinogen According to Sef Sef Churg and Hammond 1964 asbestos is a proven carcinogen responsible for both pulmonary and intestinal cancer Eighteen samples of commercial talcum powders used as baby powders shave talcum powders and spray talcum powders in a wide price range were ex- amined Labels on the commercial con- tainers did not indicate either the pres- ence or the percentage of impurities of the commercial powders METHODS OF STUDY The qualitative mineralogy of the samples was determined by ray analysis utilizing a Phillips Model 12045 60 cycle ray diffractometer Quantitative de- terminations of the various minerals and their textural characteristics were made with a Leitz Dialux petrographic microscope Percentages listed in Table II were computed by using a mechanical stage and a millimeter point count totaling fifty millimeters RESULTS The results of the ray and scopic analyses are presented in I and II microTables Table I lists the various minerals which Sample Number I 2 : + 5 6 7 3 10 10 11 12 13 14 15 TABLE L Qualitative Mineral Analyses by my Diffraction Talc x x x xX x x x x x x x x x x x Asbestosform Minerals Serp Trem Anth x. x x x x MM x MM x x x M x x M -- MM MM MMM Carbonates x MMMM MMMM MMMM MMMM Anhy- date x x x x x x x x ^^^ ^^^ ^^^ MM MM Cay Mica x x x x x x x x x x x x x x x Misc Mins x x x x x x x x x x x x xX x x 7 x 13 x MMM x x * Additives Additives and inert minerals and compounds MM MM x MM MM x ASBESTOSFORM IMPURITIES Figure Photomicrograph of sample 1 showing the distribution of talc flakes varying in width from 0.05mm to 0.20mm The edges of the individual flakes that are birefringent white should not be confused with asbestosform minerals Crossed Nicols Figure Photomicrograph of talc lake found in sample 2 showing bire fangent edges Slightly Crossed Figure PhoNtiocomliscrograph of sample 3 showing distribution of asbestosform minerals in a musco- vite matrix Slightly Crossed Nicols of 8 Figure Photomicrograph of sample showing asbestosform tremolite Figure Crossed Nicols 4 Photomicrograph of sam showing distribution of C. Nicois ate minerals Uncrossed Nicois & occur in the eighteen sam ? mercial talcum powders In # talc Figures 1 and 2 all stain asbestosform minera which are defined as fibro actinolite and *. Figures 3 and 4 Carbons eous minerals were also det samples Figure ) Table II summarizes the of minerals found in the p varies from 48 percent in 92 percent in samples 2 and form impurities range from samples 10 and 12 to 46 pe ple 13. Carbonate micacecu laneous minerals range from percent in samples 2 3 1 to 20 percent in samples - DISCUSSION Substantial amounts of mineral impurities occur : eighteen commercial calcur vestigated although the la impurities Tremolite normal impurity found in from metamorphosed magn ate racks while serpentin phyllite are common acce TABLE II Quantitative Sample Number I bu 66 0002 cg SRESTOSFORM IMPURITIES = od tomicrograph of sample 1 wing the distribution of talc ces varying in width 5mm to 0.20mm The edges the individual flakes that are efringent white should not confused with asbestosform nerals Crossed Nicols otomicrograph of talc and in sample 2 showing bire igent edges Slightly Crossed cois otomicrograph of sample 3 Owing distribution of asbestos- . m minerals in a musco- matrix Slightly Crossed cols otomicrograph of sample 8 owing asbestosform tremolite ossed Nicols atomicrograph of sample 4 owing distribution of carbonminerals Uncrossed Nicols DAVID W. SNIDER DAN E. PFEIFFER AND JOSEPH J. MANCUSO 67 ocar in the eighteen samples of comm.ial m.ial talcum powders In addition to tale Figures 1 and 2 all samples contain asbestosform mineral impurities which are defined as fibrous serpentine actinolite and anthophyllite Figures 3 and 4 Carbonate and micac- eous minerals were also detected in most samples Figure ) Table II summarizes the percentages of minerals found in the powders Talc varies from 48 percent in sample 13 to 91 cercent in samples 2 and 10. Asbestosform impurities range from + percent in samples 10 and 12 to 46 percent in sample 13. Carbonate micaceous and miscellaneous minerals range from a trace 1 percent in samples 2 3 11 16 and 18 to 20 percent in samples 4 and 12 DISCUSSION Substantial amounts of asbestosform . a impurities occur in each of the eighteen commercial talcum powders investigated although the labels listed no impurities Tremolite is the normal impurity found in talc derived from metamorphosed magnesium carbonate rocks while serpentine and anthophyllite are common accessory minerals in talc produced from altered ultrabasic rocks Cooper and Hartwell 1970 However the labels of the commercial samples did not designate the source of the raw talc A wide retail price range was represented by the eighteen samples investigated but the percentage of asbescosform impurities was not found to be related to price ACKNOWLEDGMENTS The writers wish to thank Dr. I. I. Oster and Miss Karen Gran for supplying the samples of commercial talcum powders and to acknowledge Drs Lester Walters and Charles F. Kahle for their assistance in the interpretation of the ray data REFERENCES COOPER J. D. and J. W. HARTWELL 1970 Tale soapstone and pyrophyllite Mineral Facts and Problems 1970 Edition U. S. Bureau of Mines Bull 650 p 1267-1281 MERLISS R. .. 1971 created rice and Japanese stomach cancer Science v 173 10 4002 p 1141-1142 SELIKOFF J. J. Chunc and E. HAMMOND 1964 Asbestos exposure and neoplasia Jour Amer Med Assoc v $ p 22-26 TABLE II Quantitative Mineral Analyses by Petrographic Microscope Volume Percent Sample Number 1 2 3 + s 6 7 3 9 10 11 12 13 14 re 16 17 18 Percent Talc Flakes 73 92 79 S7 82 72 9 61 80 92 86 76 48 90 XORK XORK XORK XORK Percent Carbonate Grains i trice Face 20 trice to 1 13 5 S 4 4. trace 20 6 4 4 trace 6 trace Percent Asbestosform Minerals 22 : 21 23 18 15 6 34 16 + 14 + NNUNGA NNUNGA NNUNGA NNUNGA NNUNGA NNUNGA 0003