Document 1gbzJMj0zEQ9p7E7qdGRnJ1Xd

A REPORT ON HEALTH ASPECTS OF FIBROUS GLASS Medic*! Seriee, Bulletin tro. 13-68 4400 Fifth Avenue Pittsburgh, Pennsylvania 15213 1968 16186 FOREWORD From time to time. sine* publication of Us first bulletin in 1935, the Industrial Hygiene Foundation of America. Inc. (IHF) has-issued medical ri* porta on aubjacta of topical interest to ita members. IHF is a nonprofit research association of industries for the advance ment of healthful working conditions and human relations in industry, and serves a unique function as the focal point for exchange of information on health prob lems allegedly arising from industries' operations! products and wastes. The Foundation's ability is vested in individuals with highly specialised scientific* technical and professional backgrounds and experience in its member organisations as wsll as in its full-time staff, its standing committees, and expert panel of advisors. Its work is therefore supported by numerous individ uals in hundreds of companies deeply committed to the advancement and fulfill ment of the Foundation's mission. At the invitation of IHF, Dr. Jon L Konrneo. Medical Director of OwensCorning Fiberglas Corporation* Toledo, Ohio, assisted in the preparation of this bulletin in association with Dr. Paul Cross. Director of the Foundation's Research Laboratory, based on an extensive review of all available experimental and human data, published or in progress. The information contained herein is presented for the guidance of the members of IHF and all those in the fields of environmental and occupational health who should benefit from this documen tation which gives evidence that fibrous glass is inert and non-injurious to health. Robert T. P. deTreville, M. D. . Sc.D. President Industrial Hygiene Foundation of America. Inc. i 16187 TABLE Or CONTENTS Foreword......................................................................................... i Introduction ..................................................................................... I Effect* of Expoiun to Fibrous CUs*............................. 2 Medicel Research Studies ........................................................ 2 Summery................ 6 Reference*........................................................................ 7 ii 16188 i. INTRODUCTION fibrous glass ia produced in two forma -- as a wool*type product pri* marily for thermal and acoustical insulation and as a textile fiber for fabnee and etrength*giving reinforcements. Since its development in the early 1930*a. fibrous glass has become one of society's moat useful basic materiale. Originally manufactured as a material for furnace filters and home insulation, fibrous glass now goes into more than 33. 000 end products. In addition to furnace filters and home insulation, major applications of wool*type fibrous glass today include acoustical ceilings, filters for purify ing water and thermal insulation for pipe, air conditioning ducts, food cold storage systems and household refrigerators, ovens and other appliances. Major markets for textile fibrous glass are: curtains and draperies, bed* spreads, table clothe, awnings, fire protective clothing and reinforcements for plastics, rubber and paper. Interest in possible occupational and environmental health problems with fibrous glass goes back almost as far as the first development work on the material in 1931. In most cases, this interest has centered on possible effects from skin contact, inhalation and ingestion of small fibrous glass particles. Results of medical research, including examinations of hundreds of persons who have worked in fibrous glass plants as long as 2S to 30 years, gives evidence that fibrous glass is inert and non*injurioue to the individual's over-all health. V 2. The purpose of this report ia to review tha finding* of the moat signi ficant of theae studies in on effort to clarify the health aapecte of fibrous glass. EFFECTS OF EXPOSURE TO FIBROUS CLASS Obviously, continued exposure to excessive quantities of any duat or fume* ahould be avoided. However, duata and fumea differ widely in their potential harm to human health. Some prove injunou* in low atmoaphenc con centration*; other* are harmlea* at high concentrations. Skin irritation occasionally results from exposure to fibrous glass particles, but this irritation has proved to be superficial and transitory. Fibrous |U>. manufacturers have always been interested in determining whether or not fibrous glass particles are injurious if inhaled or ingested. As a result, they have cooperated in many medical research studies conducted over the past three decades by medical scientists and physicians considered to be authorities in their medical apeciajites. Based on existing medical evidence dating back to 1940 through to present, airborne fibrous glass is not a hasard to general health. Hundreds of fibrous glass workers have been exposed to hlgher-than-avcrage concentrations of airborne glass particles virtually every working day for as long as 25 to 30 years without exhibiting any pattern of lung disease that can be attributed to exposure to fibrous glass. MEDICAL RESEARCH STUDIES Among the most significant of medical studies conducted to date on fibrous glass were the investigations ia 1963 by George W. Wright. M. D. Head of the Medical Research Department of St. Luke's Hospital in Cleveland. 16190 3. The study is s review of periodic chsst x-rays. medical rseords sad job exposure historiss of 1, 401 employ**# *t the lsrgest sad oldest fibroue glass manufacturing plant. Noo* of these workers had been employed less than 10 years. Many were employed at the plant upwards of 25 years. The report gives the purpose of the research in its opening sentence: "The question to be explored is whether or not prolonged exposure of workers to an environment containing airborne fibrous glass coated with phenolic resin... is associated with a recognisable pattern of roentgenographic abnormality." i The report's summary states as follows: l "The effect, as revealed in the chest roentgenogram, of ten to twenty-five years of exposure in an environment containing airborne particles of fibrous glass has been studied. No un usual pattern'of radiologic densities was observed. "The frequency of various radiologic appearances known to occur in the general population was no higher in those with greatest exposure than in those with the least." Another important study^ mad* between 19S6 and 1958 by Paul Cross. M. D. . Research Professor. University of Pittsburgh. Graduate School of Public Health: Senior Fellow, .Mellon Institute; and Director of the 1HF Research Laboratory. Pittsburgh, Pa. . was a laboratory animal study consisting of three parts: 1. determination of the pulmonary response resulting from exposure 3 to high concentrations of respirable, airborne glass particles {hundreds of millions of particles per cubic foot) and the injec tion into the lungs of both coarse and fine glass particles to * determine pulmonary response to the glass; Respirable means sufficiently small to gain access to the deepest lung tissues, ordinarily 3* or lees in diameter, i. e.. microscopic and submicroscopic fixed particles. Fine particles used in this study were approximately l in diameter. Coarse particles* put through a 325 mesh sieve (U. S. Standard No. 40) were SO** or less ia diameter with a few pertides measuring as much as 400 or 0. 4 mm. 1 61 91 4. 2. to document the effects of th massive ingestion of ground glass of microscopic dimensions (laboratory animals were fed a diet ' containing S0% finely milled glass flakes for one year); and 3. to study the effects resulting from dusting the eyes of laboratory animals with finely milled glass dust and glass flakes. Following are excerpts from Dr. Cross' summary and conclusions: "No effect of glass dust and glass flakes was demonstrable upon the cornea or the conjunctiva of the eyes. "No toxic or traumatic effect was demonstrable upon the gastro intestinal tract. There was only slight depression of the growth rate when rats ingested a diet containing as much ground glass ($0%) aa food. This depression was due entirely to a lower food intake. "The pulmonary changes in guinea pige exposed to fine glass dust for one year and those of rats either exposed to the same dust or given injectione intratracheally with it were minimal in character and consisted only of email focal aWtol^r dust cell collections without fibrosis.. .Coarse glass dust injected into the lungs of rats behaved like inert foreign material...." Moreover, ae recently aa April. 1968. Dr. Cross reaffirmed the conclusions as follows: "Based on all completed and in-progress experimental and human data of which we have knowledge, fibrous glass dust should be claseified as 'inert', i. e., without demonstrable pathologic effect. "There should be no adverse effects to health irom inhalation of glass dust of respirable sise. whether in pulverized or filamen tous forms. "* Two of the more recent ioveetigatione were reported in the July. 1967, issue of the Journal of Occupational Medicine. In one article4 Carey P. McCord, M. D., Professor Emeritus of the Institute of Industrial Health at * From a memorandum to Robert T. P. deTreviUe. M. D. from Paul Cross. M. D. dated April tt. 1968. V* 1 61 92 5. the University of Michigan. Ann Arbor. Michigan, summarised his investiga tion of fibrous glass manufacture and technology with this statement: "Fiber glass, like all common forms of glass, is a chemically inert substance. It possesses no known toxic properties. On a mechanical basis, spieules may abrade the skin leading to superficial and transitory irritation. Among fiber glass makers, particularly new workers who are most exposed, skin irritation occurs, but is not remarkable...." la the second article.* Ahmed N. M. Nasr. M. O.. also of the Institute of Industrial Health at the University of Michigan, reviewed the world's litera ture covering health aspects of exposure to fibrous glass, These excerpts from the report summarise Or. Nasr's conclusions: "As far as can be ascertained from a search of the American and European literature, available evidence indicates that fibrous glass is a relatively inert material with no fibrogemc or other significant toxic properties. " 6 A study of human skin reaction to contact with fibrous glass vas con ducted in 1957 by Eldred R. Heisel. M. D. , formerly Chief. Division of Derma tology. and John H. Mitchell. M. D.. Clinical Professor and Head of the Division of Allergy. Ohio State University. Columbus. Ohio. This study included both patch and rubbing tests on two groups of human volunteers. One group of 50 white women had never been exposed to fibrous glass. The second group con sisted of 92 persons who had been exposed to fibrous glass for periods ranging from less than one year to as long as 15 years. Excerpts from the report's summary follow: .. We were unable to induce sensitivity in the first group (e. g. . 50 women) and no sensitisation reactions were noted in the second group (e. g.. 92 persons). "Reactions were observed when finely cut fibers were applied to the skin. These varied directly with the else (diameter) of the fiber and were Interpreted as being due to mechanical irritation.... 161 93 b. SUMMARY Medical investigations and scientific medical studies conducted by highly qualified specialists in skin and lung diseases have shown fibrous glass to be a biologically inert substance that produces no permanent injury to individuals exposed to it. The documented evidence substantiating this conclusion includes in vestigation of the health of hundreds of fibrous glass workers who have been exposed to the material on a regular basis for as long as 25 to 50 years. Medieal publications on fibrous glass include other studies, investi gations and literature reviews. Several of these are listed for information 7- 15 purposes. V 1 61 94 7. REFERENCES 1. Wright. George W. : Airborne Fibrous Glm Particles. AMA Arch. Environ. Health J_6:175-181. February 1968. 2. Groee. Paul. M. L. Westrick. and J. M, McNerney: Glass Duet: A Study of It* Biologic Effects. AMA Arch. Industrial Health 10-23. January 1960. 3. Hatch. T. F. and Paul Gross: Pulmonary Deposition and Retention of Inhaled Aerosols. Academic Press. New York. .964, 4. McCord. Carey P.: Fiber Glass: Chemistry and Technology. J. Oec. Med. 2:339-344. July 1967. 5. Nasr. Ahmed N. M.: Pulmonary Hasards from Exposure to Glass Fiber*. J. Occ. Med. 9:345-348. July 1967. 6. Heisel. Eldred R. and John H. Mitchell: Cutaneous Reacionto Fiber glass lnd. Med. fc Surg. 26:547-550. December 1957. 7. The Saranac Laboratory for the Study of Tuberculosis of the Edward L. Trudeau Foundation. Annual Report. 5aranac Lake. New York. 1940. 8. Siebert. W. J. : Fi'oerglas Health Hazard Investigation. Industrial Medicine. Jan. 1942. 9. Sulzberger. Marian B. and Randolph L. Baer. Dept, of Medicine. York University College of Medicine: The Effects of Fiber C > on Animal and Human Skin. Industrial Medicine. Oct. 1942. 10. Irwin, J. R. . Boeing Aircraft Company. Seattle. Washington: Fiberglas Plastics---Industrial Medical Aspects and Experiences. Industrial Medicine. Sept. 1947. 11. Schepers. G. W. H. . T. M. Durkan. A. B. Delahant. A. J. Redhn. J. G. Schmidt, F. T. Creadon. J. W. Jacobson, and D. A. Bailey: The Bio logical Action of Fiberglas-Plastic Dust. Arch, of Industrial Health J_8: 134. 1958. Bjure. J. . B. Soderholm and J. Widminsky: Cardiopulmonary Function Studies in Workers Dealing with Asbestos and Glasswool. Thorax 19:22. 1964. 13. Keane. W. T. and M. R. Zavon: Occupational Hasards of Pipe Insulators. Arch, of Environ. Health ^2:171, 1966. 16195