Document zo4GjJE8jXN3MvJ7oa3ay90X7

0 H O F F MA N N - LA R O C H E INC. N U TLEY NEW JE RSE Y 07110 December 18, 1973 Hearing Clerk Food and Drug Administration Department of H ealth, Education and Welfare Room 6-88 5600 Fishers Lane Rockville, M aryland 20852 Re: Proposal by FDA to R estrict the Use of Talc in Food and Drugs on the Basis of Asbestos Content 38 FR 27076, September 28, 1973_________________ Gentlemen: Concerning the captioned proposal, Hoffmann-La Roche Inc. has the following comments. Hoffmann-La Roche In c . is a New Jersey corporation engaged i n , among other th in g s, the development, production and sale of various pharm aceu tical pro d u cts. Certain of these products contain talc as an in g red ien t. In this connection, we are interested in the proposed restrictions of the use of talc in food and drugs on the basis of asbestos content appearing in the Federal R egister of September 28, 1973. Our comments are directed toward the specific test procedure set forth in proposed Section 121.2006(c) (2) . After an intensive study of this a re a , we believe that this proposed test is not as accurate as is desirable and reasonably practicable in terms of differentiating asbestos from talc or other mineral substances commonly found in talc. Additionally, the test is unnecessarily time consuming. 75P'OS.(j?\ P HARMACEUT I CAL S FINE CHEMICALS VITAMINS cao M ED ICA L E L ECT R O N ICS DIAGNOSTI CS *f HOFFMANN -L \ ROCIIE INC NUTLEY NEW JERSEY 2- - To meet these drawbacks , a somewhat modified test has been developed and is set forth in Attachment A . This modified test appears both more accurate and more efficient than that contained in the original Federal Register proposal. The modified test is not wholly satisfactory, how ever, because like the proposed te s t, it fails to differentiate asbestos from certain minerals frequently encountered in ta lc . Hence, this modified test, like the proposed test, w ill, if implemented, result in some erroneous reje ctio n s. It is therefore recommended that the modified test be adopted by FDA in place of the proposed Section 121.2006(c)(2) as part of the standard under which talc should be examined for asbestos content; but that implementation of this regulation be stayed until July 1, 1974 so that supplem entary tests as described below may be explored. The modified test is important because u nder FDA's proposed method of testing for chrysotile fibers and amphiboles, it is often difficult in practice to spot the presence of chrysotile fib e rs. The modified test utilizes a larg er differential in the indices of refraction of chrysotile and the index liq u id , which substantially facilitates visualization of the chrysotile. The change significantly increases the accuracy of the test. The modified test does not result in any loss of accuracy in testing for amphibole content. In certain unusual instances , there is a possibility that the modified test will count talc particles as chrysotile. An additional specific test, adapted from one aspect of the proposed Section 121.2006(c)(2) , is included in the modified test to allow for this contingency and hence prevent erroneous rejections. This additional test would need be used only rarely. The modified test, as opposed to the proposed test, results in practice in a reduction of test time from approximately thirteen days to about three days. The modified test is not fully acceptable by itself, how ever. There is a group of several minerals commonly found in talc w hich, under either the proposal or the modified test, will yield a positive test for  HOFFMANN-LA ROCIIE INC NUTLEY NE^ JERSEY -3- either chrysotile or amphiboles even though these substances are absent. We have tentatively identified these m inerals as chlorite, kaolinite, and epidote, although there may be additional similar non-asbestos minerals within this g roup. Kaolinite interferes with the optical test for chrysotile, and chlorite and epidote interfere with the optical test for amphiboles. Details on refractive data for chlorite, kaolinite, and epidote, and background data from Bureau of Mines publications indicating the existence of such minerals in talc , are for your ready reference contained in Attachment B . Because the proposed modified test is not fully satisfactory, we presently plan to investigate use of differential scanning calorim etry, infra-red spectroscopy, and X -ray diffraction to differentiate asbestos from the non-asbestos m inerals noted and tru st we will have further information available at an early d ate. On the basis of the foregoing re a so n s, we are v ery concerned that implementation of the proposal, in either its original Federal Register form or in the suggested improved modified form in Attachment A, could, by resulting in erroneous rejections of talc caused by mistaking the above minerals for asbestos, lead to critical difficulties in obtaining usable talc supplies. Accordingly, we strongly recommend that any implementation of the regulations in either the proposed or modified form be stayed at least until July 1, 1974 so that alternate supplemental testing methods may be explored. Respectfully submitted HOFFMANN-LA ROCHE INC. EBA: Wbp Attachments Submitted in quintuplicate E . B . Anderson Vice President