Document BvZEL5Zo5xE4N2B5DRVq8Q7Jk

American Industrial Hygiene Association Journal Volume 29 MAY-JUNE, 1968 Number 3 Yant Memorial Lecture: Occupational and "Non-occupational" Asbestosis in Finland ............................................................................................................................................. 195 Leo Noro, M.D. The Mammalian Toxicity of Methacrylonitrile ............................................................ 202 U. C. Pozzani, E. R. Kinkead and J. M. King, D.V.M., Ph.D. Experimental Evaluation of the Threshold Limit of Cristobalite-- Cal cined Diatomaceous Earth ......................................................................................................... 211 W. D. Wagner, D. A. Fraser, P. G. Wright, O. J. Dobrogorski and H. E. Stokinger The Work Environment of Insulating Workers .......................................................... 222 L. LeRoy Balzer and W. Clark Cooper, M.D. ~ Coproporphyrinuria and Urine-Lead Findings: Fifteen Years of Experience 228 Martin Ornosky Distribution of Mercury Among Blood Fractions and Serum Proteins ......... 233 H. Cember, Ph.D., P. Gallagher and A. Faulkner Determination of Ethyl Benzene and Styrene in Air by Ultraviolet Spec trophotometry .................................................................................................................................... 238 Robert K. Yamamoto and Warren A. Cook Separation and Identification of Polycyclic Hydrocarbons in Rubber Dust 242 Charles G. Smith, Ph.D., Carl A. Nau, M.D., and Charles H. Lawrence, Ph.D. A Pneumatic Control Device for Preparing and Dispensing Gas Mixtures 248 J. Brennan Gisclard A Technique for Determining Penetration as a Function of Particle Diameter ................................................................................................................................................ 252 Mansoor Taheri, Ph.D., and Richard K. Barton An Instrument for Sizing and Counting Airborne Particles ............................... 257 A. E. Martens and ]. D. Keller An Experimental System forAerosol Research ............................................................. 268 Francis J. Haughey, Ph.D., and Raymond M. Manganelli, Ph.D. A Comparison of Leak Test Procedures for Sealed Radium Sources.................. 279 Jerry O. Morris, Donald F. Menker and Maxwell Dauer A Stochastic Model Describing Bacterial Aerosol Concentration in Enclosed Spaces ............................................................................... D. R. Heldman 285 A System for Appraising Airborne Populations of Pollens and Spores............. 293 Paul L. Magill, Earl D. Lumpkins and Judith S. Arveson Community Air Quality Guides .................................................................................................... 299 Hygienic Guide Series ........................................................................................................................ 304 President's Page ...................................................................................................................................... A_2 Meetings in Prospect ........................................................................................................................ A_4 American Industrial Hyciene Association Journal, published bi-monthly bv the American Industrial Hygiene Association. Dohrman H. Byers. Editor in chief; Richard F. Scherberger. Editorial Manager- Tames O Pirrre TT Allen E. Dooley. Thomas T. Mercer. Bruce A. Hertig. and John W. Clayton. Jr.. Associate Editors Editorial' ?o"'n10H Broadway Cincinnati Ohm 45202 George D. Clayton. Publications Manager. Business office. 14120 Prevost, Detroit. Michigan 482.L. The subscription price is $lo per vear in U.S.A.. and S16 elsewhere Single copies, when available, may be purchased from the business office at $3 per copy. Copyright 1968 by the American Industrial Hygiene Association. The .Association reserves the right to edit all advertisements and to refuse advertising copy when it does not meet the high standards adopted by the Association Library of Congress Catalogue No. 37-3191. ' Second class postage paid at St. Paul. Minnesota Printed for the American Industrial Hygiene Association by THE BRUCE PUBLISHING COMPANY, SAINT PAUL, MINNESOTA, 55114 ' A-3 PLAINTIFF'S EXHIBIT 5of\-d3/ American Industrial Hygiene Association Journal 197 as 2500 B.C. or 4,500 years ago people in Finland knew how to add fine asbestos fiber to raw material for pottery. The technical significance of this discover)' is obvious. In the same way that asbestos is now used to improve tensile strength (in the armoring of cement products, for example) so it was once used to strengthen the sides of lightly fired pottery. When the material had been strengthened, the sides of the vessels could be made thinner. In this way cooking utensils were produced which were not only lighter in weight but in which food could also be cooked more quickly. This surprisingly mature tech nical invention found also a practical adapta tion which commands respect for the eco nomic instincts of those forefathers whom we often regard as very primitive people. Asbes tos pottery was not limited to being a pro vincial specialty of eastern Finland; it spread over a wide area of Finland, Scandinavia, and Russia. The asbestos pottery' as found in Finland and in neighboring countries is unique--nowhere else have discoveries of that kind been made! This use of asbestos also illustrates that ex posure of man to occupational asbestos in handicrafts has at least a 4,500-ycar-old his tory in Finland as well as the non-occupational exposures in asbestos areas. But only since 1918 have we had a modern industrial exposure of workers in quarry, mill, and fac tories. Our eastern neighbor, Russia, started the production of asbestos as early as 1712 during the reign of Peter the Great. Their production at present is already approxi mately two million tons per year, half the total of world production per yeaT and twice as much as the United States annually uses. Finnish Asbestos The present production in Finland is only 11,000 metric tons per year of anthophyllite asbestos. The asbestos dust in the quarry and mill mineralogically contains: Anthophyllite Talc ' Chlorite 30-75% 20-60% 3-13% The theoretical chemical composition is (Mg, Fe2+)7 [(OH)j (ShOnh]- There are small amounts, perhaps smaller than in Canadian asbestos, of some metals such as Ni, Cr, Co, which might have some cancerogenic interest. Levels of Exposure to Asbestos Dust Unfortunately the exposure levels at plants have been systematically measured only dur ing recent years. Twenty years, ago, before the management of the quarry and mill changed, the dustiness was, especially in the mill, rather great. One could only see a few meters ahead. The level of dust was surely many times higher than what our threshold limits indicate it should be. This great expo sure reflects in the frequency and severity of our asbestosis cases, which will be presented later. The present situation of dustiness will be reflected in the morbidity of the next ten to twenty years. In the entire asbestos industry approximately 225 different jobs have been examined. In three-fourths of them the level of dust is under the threshold limits, but it is higher in the remaining one-fourth. We have used: (a) gravimetric samples taken with electrostatic precipitators (MSA) and/or with membrane filter field monitors (Millipore Filter Corp., Type AA), and (b) breathing zone samples taken with an impingcr (MSA) for particle counting and siz ing under the microscope. X-ray diffraction methods are used also. In the mill and quarry the total quantity of dust varies from 7.5 to 100 mg/m\ In other working places the level of dust varies from 0. 3 to 10.6 mg/m3 or 11 to 2,400 particles!/ cm3. Only 1% to 5.4% of the total dust (impinger-method) has been fibrous particles, 1. e., 5 fx in length, the length being three to four times the width. In this connection I would like to mention that in eastern Europe (the Soviet Union, East Germany) the thres hold limits are somewhat lower than the western ones: 2 mg/m3 or 100 to 150 par ticles/cm3. The level of industrial hygiene in Finland is not yet satisfactory, and unfortunately we must expect still more asbestosis cases. Medical Findings The first medical survey in our asbestos industry was made in 1946 by C. Wegelius.