Document VK20LdDwM9n3QEM78oROQmmbp

FILE NAME: RT Vanderbilt (RTV) DATE: 1974 Oct 9 DOC#: RTV216 DOCUMENT DESCRIPTION: J-M Memo RE FDA Optical Methods for Counts of Asbestos Minerals Meeting OSHA Definition in Four Samples Produced by RT Vanderbilt 1 j.t~ ,,*-<***** ; Johns-ManviHe S r s t e r h a l - G a r r e s p K u A'AU?'**> R. S. Lamar. - R&D Doto: October 9, 1974 tom: v. E. Wolkodoff R&D Copies: Distribution at End of Memo Subject: FDA OPTICAL METHODS FOR COUNTS OF ASBESTOS;;MINERALS MEETING . OSHA DEFINITIONv:iN FOUR- TALC 'SAMPLESiPRODUGJED^B^Rv T.: ' VANDERBILT COMPANY Through J. .P, L e i n e w e b e r h a s requested that this memorandum listing asbestos, fa^br^counts.' o n >four samples<[of talc; from R . T* Vanderbilt^jGompanyr{submitted .by Charles Wagner Company )^be--n^1ii^^esk 'oh -Friday, October 11,.1974. Mi The R., T. Vanderbilt Company talc samples are identified as follows: 1. Lab. No. RC-74255-1 2. Lab. No... RC-74255-2 3. Lab. No. RC-74255-3 4. Lab. N o . RC- 74255-4 Nytal .200 : Nytal 400 Asbestine 3X Asbestine 325 Samples are extremely complex, due to types of asbes to s e e i n g present, t he J -M. modified optical:; method ion be-'used for each determination ,b u t ,rather we had to use the FDA Microscopical Defection->of:Asbestos in Talc by Arnold E . Schulze and:William V .<Ei'senberg; issued .on August 20, 1973. The J-M.modified optical technique, however, was used on each samples (clarified Millipore'membrane) in conjunction with Zernecke phase contrast microscopy;as a check on;vfhe total, number of fibers in each sample. .lin^ail.vtestSionly;fibers ,meeting OSHA definition were counted; that-is,./at least a 3:1 aspect ratio jand. fiber lengths have to'te- at least 5 microns pr. longer Total number of a. Nytal 200 b. Nytal 400 c. Asbestine 3X d . . Asbestine 325 fibers]per. mg in each sample: 1 y055,0001-fibers/mg 2,146,000 fibers/mg 1,460',000"; fiber/nig 1 ;526/000 fibers/mg 5.. Fibers per mg of each. /Asbestos Oomponenb for. the four - . w ... A ..-;.,-.-. : xa-J : y- CRMC-ELS-005164 .*.6. R. -.'S. Lamar. (2) October 9, 1974 samples studied are as follows: SAMPLES- 20 Nytal 400' Asbestine 3X TREMOLITE 604#.p00/mg . 1,931,000/mg 876,000/mg . CHRYSQTILE 300,000/mg 86,000/mg 561,000/mg AifiOPHYLLITE : :--- :----- :-- .1 15.1,000/mg u . 129\000/mg . 2 3 ,000/mg Asbestine 32.5. 9 9 2 ,000/mg 503,000/mg 31,000/mg yfrn The .pr:edQjminkht. -fiber^in^'each sample is Tremolite which can be .somewhat- iblocky, ;>With clipped ends,>is very harsh, but most .are ;.;h&rr'b^aife . T h e >;Chrysotile . ranges 'from'sijilcy^:(ver^^ few fibrils, ^percentage) , bundles of. numerous fibrils. . In:., general, the..^brysotile'-Jls.-Gohsi&ered medium-harsh to. harsh. The CharacterizedIby^haying: very narrow diameters,.-iDfeing^extrem^ry -;rigi:d>7~be^ spear-like since vindiv^idual;;..fibers-`-'can-MH6w.pdne-r:ehd as acicular (heedie-likd)" and others s h o w a double'' termination of acicularity 6 . By transmission electron microscopy (TEM)., six plates were taken of each sample. One print.of each sample t o . show at least ia.. few :Ghr^sotile.;fibersv:are:iattadhed;:and the-magnification'is.11.;0D0X. At this.magnification 1.1 cm equals one micron. The ,'TEM plates on file are as follows : a . ' N y t a l 200 b . 'Nytal .400; c. . Asbestine 3X d. Asbestine 325 TMImate'i Nos'.;23QltA-F TEM' Plate Nos. 2302 A-F TEM Plate. N o s . .2303 :A-F TEM'Plate Nos. 2304 A-F All plates were taken at 4400X, and. after enlargement . for prints., th magnification would, be 11,0.00.x. All TEM plates were taken, on our RCA EMU-3B electron microscope. We had planned to use.a better mo d e l , Philips 200, at The Denver Research Institute for greater. CRivfC-ELS-005165 *3B?OBCgWi... . r ' ' ' ' -y- R. S . Lamar ' - ' " t ' .:. V - . :- 1 ................ ;. ; . ' ' -- 111HUHI'll : -:.'.r"y.i- J , ; ^ . Jr ,4?*r .' '*1. So- >- ; , '. V, */ wp ', HB!$r j -'-'rV <3j , pip. October 9, 1974 clarity , better resolution./ obtainv:plates.:;:;at .higher m a gni-, .-v fication and do selected area electron diffraction to prove the identity of the asbestos minerals (which cannot be done onlour /RGAriinodel) , but the instrument at DRI was not available: :for our :use at the.^txmb>;:;h^ih'-i'a-li' probability even if available/ the work .cou-lcb hot'ihav/bh ^finished by Octoberilly, 1974, since the optical work took a great deal of time.'. / If better TEM'micrographs are needed with selected area electron diffraction;patterns for your PDA presentation, and if y o u s o m e h o w can get 'additional time before the presentation, X ^111. make arrangements: for our use o f th e, Philips 200 electron microscope at DRI. z V. E. Wolkodoff Applied Research Section jc Distribution: R. P. Carter E. M. .-Penner Paul Kotin, M.D. W. B. Reitz F. J. Solon, Jr; G. L. Swallow. A. C . F ...Finkbiner, J.' A.. .McKinney; ; H.. R. Kefe. P , A. Martinson C. J. Sulewski W. L. VanDerbeek R. G. Riede - -4N ' - 4N ` 4N . - 4N - 4N 4N I I I - 5W .- 5W . - '2W . 2W - 2W - 2S - 2S F. L . Pundsack J.:.P; Leineweber W. C . ''Streib - A. J. Mciarthur. S . Spell ( NOTEBOOK 4454 pp. 70-77 w%&. CRMC-ELS-005166 'K4 Nv t!i 200, RC 7 r r; __ '] ;M-2 0 i-U L,OOCX CRMC-ELS-005167 'i'KM Ny La J 4 00. !;,OOn CRMC-ELS-005168 TEM Asbestine 3X, RC 74255-3 EM-2 303D I I ?00OK CRMC-ELS-005169 CRMC-ELS-005170