Document OEjRr1ddv2oN04gOR4JO01dK

FILE NAME: CTFA (CTFA) DATE: 1973 Dec 10 DOC#: CTFA003 DOCUMENT DESCRIPTION: Unpublished Internal Report REPORT OF CTFA TALC SUBCOMMITTEE ON METHOD TO DETECT CHEYSOT1LE AND TREMOLITE IN TALC. December 10, 1973 The Scientific 'Advisory Committee of the Cosmetic, Toiletry 6 Fragrance Association, 1625 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, 1973. The present membership of the CTFA Talc Subcommittee is shown on an attached sheet. At the first meeting of the Subcommittee, it was agreed to submit several samples of talc to r..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-duplicated code numbers : Italian Talc Montana Talc Montana Talc Vermont Talc Alabama Talc No. Carolina Talc Source I Source II In addition, a sample of Italian Talc spiked w/w with 1% chrysotil and 0.15Z treoolite was sent to each participant. The participants were aware that the sample was spiked, but did not knew the percentage of spiking. The attached table summarizes all reports submitted: Final Report (Over) Sample , No. of Fibers With R.I. Greater ' Ilian 1590 No. of Fibers With R.I. Less Than 1574 Status With Regard to Proposed FDA Method Dr. John A. Refiner (U. of Conn.) for Avon Cont'd Montana-I 0 5,844 Montana-H 13 9,281 Alabama 26 15,125 Vermont 41 165 No, Carolina 14 11,852 Fails chrysotile Passes trenolite Fails chrysotile Passes trefoilLe Fails chrysotile Passes trenolite Fails chrysotile Passes trcmolite Fails chrysotile Passes troiiiolite Spiked Italian Montana^1 Montana -H Alabama Vermont No. Carolina Dr. Tryeve Baak of United Sierra 3,000 1,000 0 0 0 o 500 2,000 0 0 0 0 0 0 Fails Passes Passes Passes Passes Passes Passes Italian Montana-I Montana-H 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 Vhittaker C:<J Fails chrysotile & 1 Fails chrysotile & Fails .chrysotile Fails chrysctile Fails chrysotile Zi Fails chrysotile & (Over) - Vc -2- X o \ * Sample No. of Fibers With IX.I. Greater Then 3590 0> v No. of Fibers With R.I. Less Than 15? Status With Regard to Pro posed FDA Method Mrs. Lucy MeCrone, MeCrone Associates for Chcsebrouch Spiked 320 Italian 120 Montana- I 0 Alabama 0 Veruion t 0 No.Carolina 0 Montana- n 0 16 0 0 0 0 0 ' 0 Passes Passes Passes Passes Tasses Passes Passes - Mr. Harold Stanley of Pfizer Italian Montana- I Montana- II.. A1 abama Vernon t No. Carolina Spiked 100 -- 100 ~-100 -- 100 100 /-v- 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 Chrysotilc Passes trerolite Fails Chrysotilc Passes trenolite Fails Chrysotilc Passes tremolite Fails Chrysotilc Passes tre.T.olite Fails Chrysotilc Passes tremoli te Fails Chrysctile Passes trcmolitc Fails Chrysotile Passes trenolite - Passes Passes Passes Passes Passes Passes Spiked Italian Dr. John A. Refiner (U. of Conn.) for Avon 632 12,930 9 Kails Chrysciile , ^Passes Tremoli le 220 1 11 Fails Chrysotilc Tasses Tremoli te Sample No. of Fibers With R.I. Greater Than 1590 No. of Fibers With R.I. Less Tlian 1574 Italian Montana-I Montana-** Alabama Vermont *No. Carolina Spilced Sample (b) (4) 53 0 0 0 . 0 0 0 0 0 0 0 0 488 16 Status With* Regard to Pro posed FDA Method for Kolr.ai 0hj Passes Passes Passes Passes Passes Passes Passes *San:ple noted to contain some fiber bundles which are rolled up talc plus some non-fibrous treiuolite 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 Products Research Lab Mr. Salvatore DLBjanra - The Mennen Company (b) (4) >, Research Center - for Kolmar Laboratories Mrr J o h n^cq ^ The Colgate Palmolive Company, Research Center The table reveals strong inconsistency between results obtained by the different scientists applying the method to the same 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 two indices exhibitel by talc plates standing on edge - varies in value between 1,539 and 1.550*. This in ccrbinstion with i.tar. 2, below, mly easily result in the mis-classii icatiori of such plates a; "fibrous, less than 1.574" and therefore chrysotile. Dr. Reffner of the University of Connecticut, in his report to Avon, admits that this factor is paramount - "counts for chrysotile are high since (talc) edges will often be mistaken for fibrms particles". -2. The iiTime'sion method for the determination of-relative refractive index be:omes unreliable when applied to extremely small (ca. 1 pnOpartide's. This is due in p3rt to the fact that particles around IJ-*1 in width approach the limit of resolution of the human eye when both size and contrast ore considered, especially when applying the Becke line technique prescribed. This will -5- 2. cause eye fatigue and resulting errors. Thus, a fine talc shard or plate on edge ray be easily mistaken for an asbestos fiber. This applies to both the chrysotile and amphibole portions of the test. i 3. It is quite likely that chlorite - a mineral of varied compo sition -commonly found in pharmaceutical grade talc - would be incorrectly identified as trcmolitc. Refractive indices for chlorite vary in the range 1.57-1.66^. 4. The examination of a 5;ample of one mi H i grant dispersed on a single microscope slide presents the investigator with a preparation which is too dense for a petrographic study. 5. The method is laborious and time consuming. Dr. Refiner quotes an analysis time of about five hours per sample and at JOHNSON & JOHNSON the investigator (D. H. Hamer) estimated at least two or three hours. 6. j ~ (b) (4) . . . :Ji in an earlier letter to the FDA suggested tTat tHere were relatively few scientists in the country vho could use the method effectively. Scientists at Bristol-Myers, Hie 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-Formin?: 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 falsc-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 chrysotile content in talc. Ve are confident that the detection and estimation of fibrous tremolite can also be done, if necessary, as a fringe benefit, at the same time. ! rrt - A "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 with updating reviews to take place as frequently as necessary. Review of Alternate 'Vrhods The CTFA Talc Subcommittee has reviewed several methods to detect chrysotile and fremolite in talc, including modifications of the optical microscopic method. These are listed with coments. 1. Optical Microscopic Method - nay be used with some modification. Possibly better selection of R.I. liquids and reduction of sample size per slide. 2. X-ray Step Scanning - A good method for detecting Lrem.oli to if we could accept about 0..?% as the threshold of detection. It does J '0 ^ not distinguish fibrous from non fibrous trer.oli tc. The simultaneous^4 j detection of chlorite makes method impractical for chrysotile. 3. X-Ray Step Scanning + Optical '.',i croscour - Acceptable as in i'2 above but the optical method continues to present the dilemma in reliable identification of chrysotile. However, this docs not rule out a major revision of the optical method to do the chrysotile identification and counting. A. X Ray Scanning; The problem of chlorite interference in the detection of chrysotile is present in all x-ray procedures thus far available. It is reliable for the detection of 1% tiemolite (both fibrous and non-fibrous). 5. Differential Thermal Analysis This procedure is capable of detecting chrysotile at the 12 level, however, it will not detect tremolite. 6. Scanning Elec tr onMicrosconv - This procedure is not capable of identi fying asbestos. Even with energy dispersive analysis, completely satisfactory identification is not possibla. 7. Transmission Electron Microsconv + Electrcn Piffraction - This appears to offer the best, most reliable method and is probably capable of detecting chrysotile and tremo3ite (fibrous), both at a level of 0.1%. It is estinnted that an installation would cost about $130M +, and is obviously prohibitive for the small manufacturer who uses talc. The amount of talc sample examined by this procedure is miniscule. Summary The CITA Talc Subcommittee tias completed its review of tlie Optical Microscopic Method for the Estimation of Chrysotile and Fibrous Tremolile in Talc, which appeared in the Federal Register, voi. 36 (>Jo. 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 tremolate 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. '/ s ' s .y *. __ George W. Sondlnnd Chairman CTFA Talc Subcommittee