Document nOKVVyj99DnJZyEVnw1QOprm

t . \ / I 1 ' ',lJLx~.L-'4~&~i ' U . J --n .V American Industriai Hygiene Association Journal May 1973 T X ii ' 7" Industrial Hygiene Summary Reports Code No. 37 s 4 7 8-C CJ ----- AND ENVIRONMENT/.! ^ MONTREAL, CAAD Vhis Jou rnal w clum tcs brief comiiiculs derived from il.iily aclmue' %%hich may be useful lo oilier members uf the profevsuni. Kdrlress your comm unications io: Kith art! l \ Seherber^cr, Meallli and S:det> K ab o u to ry , IWniihn^ 320, Koduk Fork Works, Kastm an K odak C o m p ati), KoiJ icsut, i\ctv York 14650. Asbestos, Talc and Nitrites in Relation to Gastric Cancer ii Recent!). Mcriiss' suggested that the high mors in the gastrointestinal tract except for incidence of gastric cancer in Japan may be a neoplasm in the mesentery of the colon.: associated with treatment of rice with talc in Wc are unable to relate that lesion to the Japan. He noted that some commercial treatment, since ashing has revealed no as "talcs" contain asbestos, which ite proposed bestos fibers in it. ii i as an ctiologic agent in gastric cancer. Mcrliss cited a report of a small excess of After intrapleural injection of 25 mg chrysotile or amositc into hamsters, we re gastric cancer in a group of insulation work ported tumors diagnosed as pleural mesothe i ers exposed to dusts containing asbestos liomas.-' Eight to 10 such t_mors were and a larger excess of puimonary carcinomas found in each of 3 groups of 50 hamsters and pleural mesotheliomas in miners who treated at this dose level.1 appear to have had mixed exposures to as We have now completed an experiment in bestos and title. He noted that some geo which the hamster-intrapleural method was logic deposits of talc arc associated with used to lest for carcinogenicity of a sample tremolile, anthophyliite and chrysolite of talc containing asbestos. For this work, varieties of asbestos, accounting for the wc obtained samples of commercial talcs presence of fibrous particles of asbestos to from Whittaker. Clark & Daniels, Inc.. New gether with platy particles of talc in some York City. A sample of cosmetic talcum commercial preparations of "talc." powder grade was seen by microscopic ex Our group has carried out tests for car amination to be composed of platy particles cinogenicity of various preparations of as typical of the mineral, talc (hydrous mag bestos through experiments with animals. nesium silicate). Another sample of a grade The present paper summarizes some results used for some industrial purposes ("-1 3 and reports a new experiment with a prep Talc") was found to be a mixture of platy aration of talc containing asbestos. A pos sible alternative mechanism involving ni and fibrous particles. X-ray diffraction analysis revealed the presence of major trites in gastric carcinogenesis is discussed. amounts of tremolile asbestos and talc and In 45 hamsters maintained throughout their lives on diets containing 1% of the a minor amount of a serpentine mineral (antigorite). chrysotile or amositc varieties of asbestos, wc found no gastric carcinomas and no tu- Each of 50 hamsters were given right intrapleural injection of 25 mg of this sam ple suspended in 0.5 ml saline. The animals T im w ork uu ip p o rlrO by U S P H S R w ca rch G ra m tV OOi-6 Iront N ational Im iU uu* of O t.c iip jlio n .il Safety Ami H ealth, un-l hy a gram fro m I'anmc L . K ip pcl Foundation. were followed for their life spans. No tu mors attributable to the treatment were found. Granulomatous lesions were com- 227 I i f I I i i ! 228 mon on pleura! surfaces, but these lesions tended to be small and focal in contrast to larger and more fibrotic lesions induced in hamsters by chrysotilc or amosite. The negative lesuits of this test for car cinogenicity of a talc containing asbestos, and our earlier test on feeding asbestos to hamsters, do not offer support to the view that asbestos-containing talc contributes to the incidence of gastric cancer in Japan. Although death rates reported for gastric cancer arc notably high in Japan in com parison to other countries, the highest re ported rate comes from Chile.4 Studies of gastric cancer in Chile have been reported from our laboratory with an hypothesis that high rates for esophageal and gastric cancer may be due to conversion of nitrates to nitrites by soil bacteria with subsequent synthesis of nitrosamine carcinogens in plants used as food or through interaction in the stomach with secondary amines in food.3 Chile has the world's largest known ge ologic deposits of nitrates, which arc used as fertilizers. Nitrosamine has been reported in wheal plants and wheat grains.1* Nitro samines can form through interaction of nitrites with secondary or tertiary amines in the stomach, and have been shown to induce esophageal and gastric cancers in rais.`-,t High concentrations of secondary amines have been reported from Japan in dried fish.9 The situation invites attention to a po tential role of the nitrogen cycle ;a environ mental carcinogenesis. A source for direct ingestion of nitrites by human populations May. 1973 arises from use of nitrites as food additives. Other potential factors in gastric carcino genesis have been recently reviewed by Haenszcl et a/.1" who found no support for the talc-asbestos hypothesis on epidemiologic grounds. 1. Mcrliss, R. R.: Talc-Trcalcd Rice and Japanese Stomach Cancer. Science /7J.-1141 (Sept. 17, 1971). 2. Smith, W. E.. L. Miller, R. Ekasser and D. Hubert: Tests for Carcinogenicity of Asbestos. Ann. New York Acini. Science /J2:456 (Dec. 31, 1965). 3. Smith. W. E.. D. Hubert, and M. IJadoIlet: Biologic Differences in Response to Lone and Short Asbestos Fibers. Amcr. hut. H\g. / I i w . J. 33: Abstract =162 (Feb. 19721. 4. Macdonald. E.. and P. Wolf: in F.pulcmiutogi(<;/. Experimental ami Clinical Sintlics on Gastric Cancer. Japanese Cancer Assn. GANN Monograph 3 (1968). 5. Zaldiv.ir. R.: Geographic Pathology of Oral. Esophageal. Gastric and Intestinal Cancer in Chile, /.isch. Krch.i/or.u'h. 75:1 (19701. 6. Hedler. L.. and P. Marquurdi Leber das Vorkommcn von Nilrosammen in N.ihrungsund F u t t e r m ittcI n . Saiiniii-Scliiiiieilehcier Arcli. Pharm. exp. Path. 259.176 (1968). 7. Sander, J., F. Schweinsberg. and H. Mcnz: Untersuehnngen ueber die Fntsiehung canceroecner Nitrosamine. im Mayen. J/oppc-Scvlei's / l u l l , physiol. Client. .149:1691 (1968). 8. Druckrcy, H.. S. Ivankowc. and D. Schmachl: Organotropc careinogenc Wirkunecn bci 65 versehiedenen N-nuroso-Verbindungen an BDRallen. /.lull. Ki ehslm u h. 69.103 (1967). 9. Kawamura. T.. K. Sakai, and F. Miyazawn: Studies on nilrosamincs in foods (IV). Dis tribution of secondary amines in foods. J. iu o il llyg. Soc. (Japan) 12.192 (1971). 10. Haenszel, \V., M. Kurihara. M. Segi. and R. Lee: Stomach Cancer among Japanese in Hawaii. J. Nal'l Cancer Inst. 49 969 (1972). MFHWaeaiiladrllliictsahiomgnhR,EeDN.seiSJiakm.ricni0lti.7hw9.In4nM0uUn.Dnini.veersity