3 7 i PROPOSED SPECS FOR ANALYZING TALC FOR ASBESTOS iProtected Document--Subject to Protective Order JNJ 000232679 1 of 7 New Brunswick, NJ. May 16. 1973 Subject: Dr. Rolle I am going to England Friday; May 25. I have been asked to bring along our proposed specs for analyzing talc for '.'asbestos.? Please get me copies of all reports, correspondence, etc., that are pertinent, plus a cover memo outlining our recommendations. England is considering method of preconcentrating the asbestos so as to be able to analyze by X?ray. They find no ?asbestos" by doing this with Italian talc.? They-find (Pooley) 0. 05% of 'a tremolite?type in Vermont. T. H. Shelley A mf c: Dr. R. A. Fuller Dr. A. J. Goudie . D12, W. Nashed Dr. D. R. Petterson ?8k ?80$ rotected Document-Subject to Protective Order JNJ 000232680 2 of 7 New-BrunsWick, NJ. I. May 22, 1973 Sub?u?:U PROPOSED SPECS FOR TALC FOR ASBESTOS i A I. Other Methods Step Scanning.X?Ray Diffractcmetry ?Advantages Disadvantages Preconcentration of Asbestos (Pooley Method) .. 7. Differential Thermal Analysis J. -Microscopy . Electron Microscopy and Petrology DisPersion Staining F. Robert Rolle, Ph. D. Present Strategy ab . cc: Dr. A. J. Goudi Dr. G. Hildic?/Emith Dr. W. Nashed '7 Dr. D. R. Petterson 231973 . \1AthD- a QHNSON LEOHNSON 8? Protected Document--Subject to Protective Order JNJ 000232681 3 of 7 have been working on a preliminary draft with Mr. George Heinze on developing a USP method for the detection of asbestos in talc. Exhibit A is the USP XIX comment proof on X-ray diffraction. Exhibit is our detailed procedure which has been submitted to Mr. Heinze, for determination of amphiboie (such as, tremolite) and serpentine (such as, in talc by scanning Xuray diffractometry. 1 . iUsing this method on Italian Talc used in SHOWER TO I lowder, we find a level of detectability of 1% for Tremolite I .and 5% . II. Other Methods Which Have Been or Are Under Consideration 'for the Detection of Asbestos in Talc Step Scanning X?Ray Diffractometry Advantages: Level of detectability better than by scanning X?ray diffraction. For example, by this method we can detect-0.1% tremolite and 3% in Italian talc (Exhibit _Disadvantage: Using the step scanning procedure. it takes one day per sample for analysis vs. a small fraction of a a. day for the scanning method. Trademark of JOHNSON JOHNSON. Protected Document--Subject to Protective Order JNJ 000232682 4 of 7 1 '1 - Preconcentration of Asbestos followed by X-Ray Diffraction AlAnalysis (Pooley Method) 1H Dr. Pooley has developed two techniques for preconcen?. 1/1) ytration of and tremolite in talc followed by iix?ray diffraction analysis. For (Exhibit D), . 'his level of detectability is 0.05% and when this method is applied to Italian and Vermont talc, no is detected.. The second technique develoPed also by Dr. Booley involves preconcentration of tremolite in talc (different procedure) followed by X?ray diffraction analysis. This technique has not been written up yet, but evidently . 'when applied to Vermont talc, 0.05% of. tremolite-type is found. The limitation of this method is that it may be too sensitive. Differential Thermal Analysis.(DTA) DTA has proven to be a relatively fast and sensitive method (at 165st for detection of in talc (Exhibit C). The DTA method is not applicable for the detection of tremolite in talc. At our suggestion, the FDA recently. purchased a DTA unit, presumably to look into this method for detecting ?Protected Document--Subject to Protective Order JNJ 000232683 5 of 7 1 '1 in 1. 1. rosco . .A. Electron Microscopy and Petrology; The areas of electron micrOSCOpy and optical microscopy (petrology) have been thoroughly evaluated_ but though, not without merit, they suffer from the following .limitations: a) require a fair degree of expertise b) in-the case of electron micrOSCOpy, we are dealing with an expensive instrument that few_laboratories have. c) pone is viewing a very small amount of material (pg) under the microscopy and one wonders how representa- W.tive it is of the bulk material. Multiply sampling and viewing under the microscopy.may eliminate this problem, but it results in consumation of a great deal of time. d) the level of detection really depends upon the amount of time spent with the micrOSCOpe. e) quantification by particle counting is very time consuming and normally not done. B. Dispersion Staining The dispersion staining method_championed by Dr. Walter throne looked initially very exciting as a quick, easy method for scanning talc for asbestos. .However, it was.found (Exhibit E) that certain non?asbestos minerals gave the same dispersion staining characteristics as the asbestos minerals. The method evidently lacks. specificity when applied to talc. 1 ?Protected Document--Subject to Protective Order JNJ 000232684 6 of 7 . . Present Strategy E- Present plans call for scanning X?ray diffraction for the 5. detection of both amphibole and serpentine asbestos in talc. ?In the case of (serpentine), Differ? 1'ential Thermal Analysis may be a good alternate method since it offers a level of detectability of 1% in talc vs. in talc by scanning X~ray ?diffraction. 1 l: Protected Document--Subject to Protective Order JNJ 000232685 7 of 7