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The following editorial was photo- graphed from The LANCET, Volume I for 1977, No. 8026, dated Saturday, 25 June 1977, pages 1348 and 1349. This editorial has been reproduced here by permission of Mr. Ian Munro, Editor, The LANCET. COSMETIC TALC PO W DER FaoM time immemorial man, like his evolutionary predecessors, has been exposed to airborne dusts. Such exposure is a corollary of living and survival. Not unex- pectedly, therefore, the lungs have efficient means of clearing themselves of inhaled particles and a functional reserve such that the accumulation of uncleared dust may be considerable before there is any obvious loss of workKapacity. However, it has long been recognised that heavy exposure to dusts, such as quartz and asbestos, may lead to loss of function and, in the ease of asbestos, to cancer of the pleura and of the lung itself. The observation that even casual exposure to asbestos may be associated with increased risk of inesothelioma, now occurring at the rate of nearly 200 new cases a year in the United Kingdom,l has brought into question the safety of other common dusts such as cosmetic talc. There are two main concerns. Firstly, will inhalation of a dust cause loss of function through fibrosis or emphy- sema? And, secondly, will it predispose to cancer? I. <imnK~. \1.. ILnJ Ik.iv, T. A. Er. ]. id. Md. 1974,3t.91. Although talc can cause granulomas when introduced into the tissues or body cavitiea,' exposure to cosmetic talc has been widely assumed not to predispose to pul- monary fibrosis. However, the fact that no association has been seen between the use of talc and loss of lung function might simply reflect the lack of methods sensi- tive enough to detect losses of function that are small compared with those due, for example, to smoking and to heterogeneity in x,-antritypsin status. For similar rea- sons any effect of talc exposure on cancer incidence would probably escape notice unless deliberately sought. Until lately facilities for studying the long-term effects of inhalation of dusts in laboratory animals have been scarce, and even now the predictive value of animal models is questionable. Thus, even in the case of tobacco smoke, where the cancer hazard to man is indisputable, duplication of the effect, by the inhalation route, in laboratory animals has proved difficult or impossible; although inhaled asbestos dust has given positive results in animats.• The possibility that talc causes cancer dramatically hit the headlines of the daily Press when workers in Car- difls reported finding talc particles in cancers of the ovary and uterine cervix. The report was greeted with scepticism because the particles were not positively iden- tified as talc, because their presence did not prove causa- tion, and because they might have found their way onto the sections as a result of contamination of tissues after removal from the body. Subsequent mineral analysis failed to confirm that the particles were talc° and the passage of six years without publication of confirmatory evidence suggests that the early scepticism was well- founded. A meeting of talc-powder manufacturers and independent scientists took place at Cardiff during May, 1976, under the chairmanship of Dr J. C. Gilson, direc- tor of the Medical Research Council Pneumoconiosis Unit. At that meeting the toxicology of talc was reviewed and the need for further information discussed. Assessment of toxicity necessarily starts with a consider- ation of the physical and chemical specifications of the test material, and this, unfortunately, is also where much of the assessment ends in the case of cosmetic talc because most of the published reports-epidemiological, clinical, and experimental-concern exposure either to industrial taln that are variously contaminated with minerals known to be hazardous or to talc of undefined physical and chemical characteristics. The long thin fibrous shape of asbestos particles enables them to be carried more deeply into the lungs than spherical particles of similar mass. The fact that the normally effective clearance mechanisms have difficulty in coping with large, long thin particles de- posited deeply in the lungs is an important determinant of the hazards from asbestos dust. Geologically, talc (which is nominally a hydrated magnesium silicate) and certain amphiboles-tremolite, actinolite, and antho- phyllite-may occur in juxtaposition and consequently talc may be contaminated with these minerals. Apart !.IIIu.n.l,ft,Ikr.,F.,Zi,chk.-Kmom,{'.Oiar.Ilr..a'n4.1%2,74, 12. 1. IA.i,, B. a., NTrtehed.l, K., Gil6 31. E., lae, P. N., Bunsrronh. A. 2, K,e.14 L C. a•.7-Cvnm.1975, 31,169. 4. B'ap.r. J. (:., nem, G.. Skld,m,e, l.'+'., Timbrtlt. V. i6id. 1974, ]9, 252. 1 Il.m,fe,.nn- W. b- Jr+lin, C. A. K. Tum4ull, A. C., Gl/fnb, K.7. Ohner. fi,~rr,n. fl..Cn+nwnws.1971.71, 266. 6. NddKk-timnh, [:.1'. ar.l. rnd.M.d. 1976, 33, 217. 448

from this, talc may contain chlorite, quartz, carbonates (such as calcite, dolomite, and magnesite), and occa- sionally other minerals in lesser amounts. During the past few years, major cosmetic manufacturers in the United Kingdom and the United States of America, as represented by the Toilet Preparations Federation and the Cosmetic, Toiletry and Fragrance Association, have drawn up specifications for cosmetic talc which ensure the virtual absence of fibrous amphiboles.''10 At present there is no direct statutory control of the quality of cos- metic talc in any country and it is questionable whether such control is necessary to bring minor manufacturers into line with the standards now adopted by the major firms• The presence of fibrous particles in talc reduces its free flow and lubricity, thereby rendering it less cosmeti- cally desirable. Such contamination is thus self-limited. More important, however, is the fact that the fibrous materials most likely to contaminate tata which do not comply with the specifications-namely, tnmatite, anthophyllite, and actinolite-are not those most clearly associated with carcinogenic hazard (crocidolite, amositq and chrysotile). Furthermore, it would be sen- sible to consider what controls, if any, are necessary for talc as used in medicines, before introducing legislation specifically in relation to cosmetic talc. . If the inhalation of particles of amphibole and silica contaminated talc dust were found to be harmless, one might reasonably assume that talc free from these materials is safe. Kleinfeld and his colleagues have stu- died the incidence of cancer and respiratory diseases in talc miners and millers in New York State. •Rte talc con- cerned, which is heavily contaminated with both amphi- boles and free silica, was initially reported to be associ- ated with an increased mortality from mesothelioma and cor pulmonale." Later the same workers reported that men employed in the mine after dust levels had been reduced had death-rates from malignant diseases that were similar to those for White males in the U.S.A. generally." Alsn in the U.S.A., Fine and his colleagues° have reported a higher prevalence of productive cough and chronic obstructive lung disease among rubber workers exposed to a non-fibrous industrial-grade talc than among control workers. From their data they cal- culated that a safe exposure level would be provided by a threshold limit value of 0-25 mg/ms mass-respirable particulate talc. In Italy, Rubino and his eolleagues14 compared the spectra of causes of death among talc miners, talc millers, and agricultural workers. The talc miners were exposed to dusts containing 3%.silica at levels far in excess of threshold limit value. Significantly more of them than of the controls died from respiratory disease, but death-rates from all forms of cancer, includ- ing lungg cancer, were significantly lower among the 7. TaM Pnp.rniotu Fcdnaron IJd., prdBcation no. 12; Cmmrts l.k. 1977. l.C.T.F.A. SPm6catun: Talc, Crennk. Carme,ic, T°ilnry .vd Fr.paoee A„onauon, lnc.,5vue 10-7.1996. 9. Tmin Pnpan,inn, Fderation Ud., analyt'ral eenhn5 77: C®nk Tak 1977 . 10. H,mer, n. H., Rdle, F. R., Scluk, 3. P. Aw, ied. Hyr. Av. ). 1916, 37, 296. 11. KlcMnfeld, M., Mntia, J.. Knvynun, 0., Lki, M. H. ArtA, ene,:. HtrA, 1%7,11, 663. 12. Klnnfeld, M., Mnutr,l-Zaki, M. H. j. asap.Med.1974,11, 3e5. 13, tlne, L. J., Pemn, J, M., Burrnb tt'. A., t8 Ber.dmn, L. 1AnA, Hh6.1996.11,195. 14. Rubme, G., Scavan, G., Piolnm, G., Rmuna C. J. xnep. Med. 1976, It, 186 miners than among the controls. By contrast, among the talc millers, exposed to dusts containing 0•OS% silica, but no detectable asbestos, at concentrations of 20 mil- lion particles per cubic foot (27 litres), there was no excess of deaths from pulmonary disease or cancer of any site compared with the control group. The deficit of lung cancer among the talc miners is plausible in so far as a similar deficit of lung cancer among coal miners seems to be real." A continuing study of over 3200 per- sons, mainly women, at a factory in Britain where cos- metic talc has been made and packed for over fifty years, has so far revealed no evidence of health bazard,1e but follow-up would need to be extended for at least a further decade before one could be confident of a nega- tive result. Other less informative epidemiological stu- dies are reviewed by Hitdick-Smith! In most of the work in animals the quality of the talc has not been specified. An exception is a report by V('ehner and otherst' who studied the effects in hamsters of repeated exposure to aerosols of cosmetic talc up to total doses of respirable particles equal to nearly 2000 times those received by humans using cosmetic talc dur- ing baby care. Exposure had no adverse effect on body- weight, survival, incidence of pathological changes in the respiratory tract, or incidence of neoplasia at any site. Another exception is the report by Wagner 1nd his colleagues,'s who saw no mesotheliomas in 48 rats after intrapleural administration of cosmetic talc whefeas 18 out of 49 rats similarly exposed to chrysotile abbestos acquired such tumours. The same workers exposed rats to cosmetic talc by the inhalation route on five days a week for up to a year. At the highest level of exposure -about three times that studied by Wehner and his col- leaguest''-there was slightly more pulmonary fibrosis than in controls, but no substantial excess of pulmonary neoplasms. A number of less relevant animal studies, all of which gave negative results for carcinagenicity, are reviewed by HiidickSmith' In summary, there is no reason to believe that normal consumer exposure to cos- metic talc has in the past led either to cancer at any site or to measurable loss of lung function. It seems unlikely that future exposure to cosmetic talc of the specifications now agreed to by major manufacturers will present a health hazard. SS. Gnldm.n, K. P.8e.7. ind. MM. 1%7. ]r, 72. 16. Tk.hons, M. L., Mi55n. a. F., Mcnn, W. K. 5. PrPer si.m al ,minu m Bidqtv, ofT.k thrd in Hetlth Produn; C.ed'Yf, May,19'!6. 17. R'ehnn. A. P., ].rvukei, G. M., Gmmn, W. C., Waunn, C. R., Cuitm, K'. W.FdCane. Tns.1977,15,121. 16. U'arner. 1. C., Bany, G., Cooke, T. 1., Hill, R. 1. 5kidmnre, Y R'. i. Pro. reMina, of P°unh Intenutional Sympmiuni m Inhald Pankln and t'.pour.Gxford,l977. 449