Document J3ERaBQL4eNQBxroDkwZBqXnK

Jjh(<y A/C Pipe Producers Association Executive Committee T0 International Affairs Committee ____ . frcC/j.F. Welch, Vice President . | su8ject Transmigration of Asbestos ACTION REQUIRED: Review for information Internal Correspondence date September 2,1982 Enclosed is the abstract of a Master's thesis -,on penetrStfiPh or transmigration of ingested asbestos. The study confirms the'"recefftly-released findings of Hallenbeck et al that there is no evidence of transmigration of asbestos in the gastrointestinal tract of rats. Full copies of the thesis are available from AACPP upon request. This research will be developed into an "A/C Advisory" and trade press release. If you have any questions, please do not hesitate to call. JFW/ccw Enclosure Executive Committee L. Ambler L. Taylor J. Cran International Affairs Committee E. van der Rest P. Dorner L. Giannitrapani P. Hart A. Saoulis R. Jalan V. Pattabhi H. Hudson C. Barton S. Al-Tarkait M. Delcourt J. Cuvelier B. Giboin G. Zaviezo J. Rodrigues Dimatit J. Schmaus Dubuc cc: A. Kahn, Esq. W.E. Smith, M.D. Brian Commins, Ph.D. Tim Hardy, Esq. 0172099204 Chrono CAPCO JEN 0012232 . Circulated: 1) Front page 2) Abstract (p. I) 3) Contents (p. Ill) TRANSMIGRATION OF INGESTED ASBESTOS IN THE RAT r\Cp M. E..MEEK BSc (Honours, Biology). IOEH 507 Code 9 45 * 72 82 A thesis presented to the University of Surrey in partial*, fulfilment of the requirements for the degree of Master of Science in Toxicology. Department of Biochemistry, University of Surrey, Guildford, Surrey. September 1981 CAPCO JEN 0012233 - .. . -1 - . *' * * *' ' \ *.S> v- v \v ;:. v^*-v.;*-< . : . * . ***' * ..>--" -v ..-. >v.. : Abstract . - -V-':'-- --------------- . ' .Y; V:''' . .v - . ; ; .``v. : ' .' '"There Is disagreement about whether or not asbestos rvi'-r.^.fibres present in food and drinking water can migrate into ,,' *,' j >*, ` * / ' *t*' ,'i ' 1' * . *i ` '' , . ,, " . ' .*,* , "* **./* r*, '.rf. ^ and;;through .the' walls`of the. gastrointestinal tract in ":' ' 'V' V' :*r- :-v" ` ' -----1A:__1 j-- ______ _ j______ _____ t__ : - ^ ; v'>' `"V ' /' ; ' - . of rats' were- examined-by light microscopy following .'injection % iy--':9A''y;: ' ; : - -;*. . of a suspension obtaining amosite fibres into the wall of ' ^ . ' iV.> the'duodenum, "following oral administration of amosite to. healthy animal's for a 5 day period and 'following oral . administration of amosite for periods up to 7 days to animals :';y with induced gastrointestinal ulcers. v: .. Injection of amosite into the wall of the gastrointestinal tract resulted in the production of granulomatous lesions V./-- . . '- '` characterised by large numbers of macrophages in which ., - . - crystals with the polarising characteristics of amosite fibres " ' : were observed. There were no histopathological abnormalities . .. .. .. . ..'in the gut wall of the healthy animals and intracellular fibres, were not observed in the animals with ulcers* following the ingestion of asbestos. There was no evidence, therefore, of widespread transmigration of asbestos from the gastrointestinal' tract of rats, even under conditions.of loss of the mucosa. The implications of these results are discussed in light of other published work. i CAPCO JEN 0012234 CONTENTS Abstract Acknowledgements- .' ' :v" ' ' 7 `` ' Units and' Abbreviations v.. ' . * '. : INxTRROODDUUCCTTXIvOJNri \ . .'.v/lV*.,*:',.' ~.-a-u-v * . ' Exposure- - V ; -: - Carcinogenicity of Ingested Asbestos ' ' Animal Studies -- .' Epidemiological Studies Transmigration of Ingeste'd Asbestos / Animal Studies i! Electron Microscopic Studies Biochemical Studies Pathological Studies Human Studies 10 V ' 15 15 ' 18 25 28 29 AIMS OF THIS INVESTIGATION 33 MATERIALS AND METHODS ' ` Chemicals Animal Husbandry Surgical Procedure - Injection of Amosite into the Wall of the Duodenum Oral Administration of Amosite to Healthy Animals Pilot Experiment - Induction of Ulcers Oral Administration of Amosite to Animals with Ulcers Preparation of Histopathological Sections 3^ 3** 3^ 3 3839 ^0 . **1 RESULTS ' . Surgical Procedure - Injection of Amosite into the Wall of the Duodenum Oral Administration of Amosite to Healthy Animals Pilot Experiment - Induction of Ulcers Oral Administration of Amosite to Animals with Ulcers V* ^ ^5 45 47 DISCUSSION >9 REFERENCES 60 . CAPCO JEN 0012235