Document k6O1dabbERE6yY27gDGeKeqon

FILE NAME: CTFA (CTFA) DATE: 1973 Dec 10 DOC#: CTFA003 DOCUMENT DESCRIPTION: Unpublished Internal Report REPORT OF CTFA TALC SUBCOMMITTEE ON METHOD TO DETECT CHRYSOT1LE AND TREMOLITE IN TALC. December 10, 1973 The Scientific Advisory Committee of the Cosmetic, Toiletry 6 Fragrance Association, 1G25 Eye Street, N.W., Washington, D.C. 20006 at a meeting held on September 2, 1973, designated that a subcommittee be set up to study the optical microscopic method proposed by the Food and Drug Administration. This method vas published in the Federal Register of September 28, 1573. The present membership of the CTFA Talc Subcommittee is shovn on an attach,ed sheet. At the first meeting of the Subcommittee, it vas agreed to submit several samples of talc to c.embers who volunteered to apply the FDA proposed optical microscopic method. The following talc samples were distributed without identification - except for randomly applied and non-duplicatcd code numbers : Italian Talc Montana Talc Montana Talc Source I Vermont Talc Source II Alabama Talc No. Carolina Talc y In addition, a sample of Italian Talc spiked w/w with 1% chrysotile and 0.15% tremolite was sent to each participant. The participants were aware that the sample was spiked, but did not know the percentage of spiking. The attached table suaaaarizes all reports submitted: Final Report (Over) Sample No. "of Fibers With R.I. Greater ' Than 1590 No. of Fibers With R.I. Less Than 1574 Status With Regard to Proposed K!)A Method Dr. John A. Heffner (U. of Conn.) for Avon Cont'd Monta-n- a-F Montana-H 0 5,844 13 9,281 Alabama 26 15,125 Vermont Al 165 No, Carolina 14 11,852 Fails chrysolils Passes trer.olite Fails chrysotile Passes t.remolite Fails chrysotile Passes tre.r.iolite Fails chrysotile Passes trerr.ol it a Fails chrysotile Passes tremoli te H* M- Spiked Italian Montana-F Montana- 11 Alabama Vermont . No. Carolina Dr. Trypcve Baak of United Sierra 3,000 1,000 0 n 0 0 500 2,000 0 0 0 0 0 0 Fails Passes Passes Passes Passes Passes Passes Italian Montana-F Montana-FI Alabama Vermont No. Carolina 8,250 18,000 29,250 21,825 3,225 20,850 Spiked sample was not run. 1,350 450 5,200 6,075 675 6,000 for Whittttaakbeer CSJ Fails chrysotile & Fails chrysotile s Fails .chrysotile ti Fails chrysotile Fai Is chrysotile Zt Fails chrysotile & (Over) Sample Spiked Italian Montana- I Alab ama Vermon t No.Carolina Montana- u / 0 ' No. of Fibers With H.I. Greater Tlir.n 1590 -2- V * ' .o \ ;; U>1 ' No. of Fibers With R. I. Less Then 157^ Status With Regard to Pronosed FDA Method Mrs. I.ucy McCrone, McCrone Associates for Cbcsebrouch 320 16 Passes 120 0 Passes 0 0 Passes 0 0 Passes 0 0 Passes 0 0 Passes 0 0 Passes Mr. Harold Stanley of Pfizer Italian Montana- I Montana- ip. Alabama Vernon t No. Carolina Spiked 100 <-*- 100 <-*-100 -- 100 100 100 < 1000 > 100 >100 > 100 >100 >100 >100 >100 Mr. David Hamer of Johnson & Johnscn Italian 0 0 Montana- I 1 0 Montana- II 25 0 Alabama 0 0 Vermont 0 0 No. Carolina 0 0 Fails Cbrysotile Passes trer.ol.ite Fails Cbrysotile Passes trenolite Fails Cbrysotile Passes tremolita FaiIs Chryscti1e Passes tremolite FaiIs Chrysctile Passes ireroli te Fails Cbrysotile Passes trer.olite Fails Cbrysotile Passes trenolite Passes Passes Passes Passes Passes Passes Spiked Italian Dr. John A. P.cffner (U. of Conn.) for Avon 632 12,930 - * 220 1,114 Fails Chryscl:1e Passes Tremolile .,-Fails ChrysoliJe Tasscs Tremoli te - 4- Sample No. of Fibers With R.I. Greater Than 1590 No. of Fibers With R.I. Less Than 1574 (b) (4) Italian 53 Montana-I 0 Montana-H 0 Alabama 0 Vermont 0 *No. Carolina 0 Spiked Sample 488 0 0 . 0 0 0 0 16 Status With' Regard to Pro posed FDA Method f for Kolr.ai (jJ/hJ Passes Passes Passes Passes Passes Passes Passes *San-.ple noted to contain sonc fiber bundles which are rolled up talc plus some noil-fibrous tremolite The following participants examined their samples but were unable conscientiously to count particles with confidence, therefore, did not report numbers: Miss Marie Jones for Dr. G. Cohen - Bristol-Myers Produc ts Research Lab (b) (4) Mr.. Salvatore DiBianca - The Monncn Company yl, Research Center - for Kolr.ar Laboratories Mr.' John Facq - The Colgate Palmolive Company, Research Center The table reveals strong inconsistency between results obtained by the different scientists applying the method to the save group of coded talc samples. This inconsistency is the result of problems encountered in the methodology. 1. The alph i refractive index of talc - one of the tvb indices exhibits 1 by talc plates standing on edge - varies in value between t.539 and 1.550^. This in ccrbinatior, with iter. 2, below, m iy easily result in th mis-classification of such plates a: "fibrous, less than 1. 574" and therefore, chrysotile. Dr. Reffner of the University of Connecticut, in bis report to Avon, admits that this factor is paramount - "counts for chrysotile are high since (talc) edges will often be nistakc-n for fibr>us particles". -2. The imrae sion method for the determination ofrelative refractive index be rises unreliable when applied to extrenely small (ca. 1 pm)par ride's. This is due in part to the fact, that particles around l>J"n in width approach the limit of resolution of the human eye when both size end contrast are considered, especially when applying the P>ecke line technique prescribed. This v.'ill -l3 - 0 > (h) 2. cause eye fatigue and resulting errors. Thus, a fine talc shard or plate on edge nay be easily mistaken for an asbestos fiber. This applies to both the c'nrysotile and amphibcle . portions of the test. i .5 3. It is quite likely that chlorite - a mineral of varied compo sition -commonly found in pharmaceutical grade talc - would be incorrectly identified as trcr.olitc. Refractive indices for chlorite vary in the range 1.57-1.66^. 4. The exanination of a .".ample of one milligratn dispersed on a single microscope slide prsents the investigator with a prparation vhich is too dense for a ptrographie study. 5. The riiethod is laborious and time consuming. Dr. Refiner quotes an analysis tine of about five hours per sample and at JOHNSON & JOHNSON the investigator (D. H. Hamer) estimated at least two or three hours. 6, I (fa)(4)_______ in an earlier letter to the FDA suggested Satthere were relatively few scientists in the country who could use the method effectively. Scientists at Bristol-Myers, The Mennen Company, Liberty Mutual and Colgate-- Palmolive had great difficulty in following the method to conclusion. 7. The proposed FDA method implies that all fibrous particles in talc having optical properties similar to those of asbestos minerals are in fact asbestos. This is probably an unwarranted assumption. REFERENCES : 1. Deer, W.A., Howie, R.A., and Zussman, J., Rock-Forming Minerals, Vol. 3, p. 121 (1962). 2. Ibid, p. 131. ***************** We have concluded that the method published in the Federal Register does not provide a truly reliable means for the detection of asbestos in talc. It results in both false-positive and false-negative findings. It is also tedious and may consume as much as one half day per sample. 'The subcommittee urges that the Food and Drug Administration defer finalizing the proposed optical microscopic method and proceed into a Phase II program which would combine FDA and Industry in a strong effort to develop a truly reliable method for measuring chrysotilc content in talc. We are confident that the detection and estimation of fibrous trcmolite can also be done, if necessary, as a fringe benefit, at the same time. - 6- We estimate that a satisfactory method will take at least six months to a year to develop. We suggest a close liaison between FDA and industry in this all-out effort viLh updating reviews to take place as frequently as necessary. Review of Alternate verhods The CTFA Talc Subcommittee has reviewed several methods to detect chrysotile and tremolite in talc, including modifications of the optical microscopic method. These are listed with coaments. 1. Optical Microscopic Method - may be used with some modification. Possibly better selection of R.I. liquids and reduction of sample size per slide. 2. X-rav Step Scanning - A good method for detecting trendi to. if we could accept about 0 .?.% as the threshold of dctc-.cticn. It does not distinguish fibrous from non fibrojs_ tremoli te. The simultaneousJ detection of chlorite mokes method impractical for chrysotile. 3. X-Ray Step Scanning + Optical Microscony - Acceptable as in f2 above but the optical method continues to present the dilemma in reliable identification or chrysotile. However, this does not rule out a major revision of the optical method to do the chrysotile identification and counting. j > 4. X Ray Scanning of chrysotile is The problem of present in all cxh- rlaoyritperociendtuerrefseretnhcues in the detection far available. It is reliable for the detection of 1% txem.olite (both fibrous and non-fibrous). 5. Differential Thermal Analysis This procedure is capable of detecting chrysotile at the IX level, however, it will not detect tremalite, 6. Scanning El a c tr onMicrosconv - This procedure is not capable of identi fying asbestos. Even with energy dispersive analysis, completely satisfactory identification is not possible. 7. Transmission Electron Microsconv 4- Electron Hiffraction - This appears to offer the best, most reliable method and is probably capable of detecting chrysotile and tremolito (fibrous), both at a level, of 0.12. It is estimated that an installation would cost about $130M +, and is obviously prohibitive for the small manufacturer who uses talc. The amount of talc saeiple examined by this procedure is miniscule. - 7- SuraiTiary The CTFA Talc Subconnittee Has completed its review of the Optical Microscopic Method for the Estimation of Chrysotile and Fibrous Tremolile in Talc, which appeared in the Federal Register, voi 38 (>.'o. 188),(p. 27076, September 28, 1973). It recommends postponement of the finalization of the proposed regulation on talc. In addition, a collaborative effort between FDA & industry to resolve a satisfactory method of estimating chrysotile and tvemolite in talc, is recommended, with periodic liaison reviews to monitor the project status. A task force of industry experts has been designated to pursue alternate methods. Ve invite FDA to participate in collaboration with the task force.