Document 0JpQeQwJernxkN3NMe80xwR4J

FILE NAME: Saranac (SAR) DATE: 1948 Oct 28 DOC#: SAR154 DOCUMENT DESCRIPTION: Confidential Letter to Vandiver Brown from Keasbey & Mattison with Comments on the Report on Asbestos Dust Experiments Supporting Keeping Some Info Private fc fA S B E Y & M aTTIKOX C o M l ^ m ' M * tM C tg a m o f a M in 4 **e m c k >* m o d v c ** A M B L E M , ?t>i'.*5TX .V ;i?:2A October 28, 1946 Confidential Mr. Vandiver Brown Johns-Manville Corporation 22 East 40th Street New York 16, N. Y . Dear Mr. Brown: Saranac Laboratory Report on Asbestos Dust Experiments Thank you very much for your letter of October 22nd together with copy of the Saranac Laboratory report dated September 30, 1948 entitled "Asbestos Pneumoconiosis" and also copy of your comments on the report which we briefly discussed over the telephone the other day. In addition, I wish to thank you for your letter of October 27th and for the kind invitation to be present at a luncheon in the Johns-Manville Corporation Board room on Thursday, November 11th, at 12:30 P.M. I accept with pleasure and will bring my copy of the report with me to the meeting. I wish to make the following comments: 1. I fully agree with the views as expressed in your memorandum sent with your letter of October 22nd. 2. The report is confidential and is the property of those who ad vanced the funds for carrying out the experiments at the Saranac Laboratory. 3. The report should be confined to the results on animals only. 4. There should be a separate later report, not a supplementary report, dealing with human asbestosis. 6. Experiments reported on to date covering tumors and pneumonia caused by asbestos dust are inconclusive. The entire paragraph No. 02 on page 39 "Neoplasm " should be deleted. 6. The number of million asbestos particles (long and short) per cubi foot of a ir is, in my opinion, a more accurate and indicative measureme than the percentage of long fibres. M r. Vandiver Brown - 2- Octooer 23, 1948 To me, after having studied the report quite carefully, the following are the most significant points: Paragraph 81, Page 34 - Comparison of Long-Fibre and Short-Fibre Dusts. " With quartz dust it has been demonstrated that the smaller the particles, the more intense is the tissue reaction, and that there is little reaction to particles larger than three microns in diameter. In the case of asbestos, however, the reverse is true and apparently only long fibres have any specific e ffe ct." Paragraph 87, Page 37 - Theory of Irritant Action of Asbestos Minerals " In view of this evidence it seem s more likely that asbestosis is caused by an unusual mechanical irritation from long asbes tos fib res." " Further support for the theory of mechanical irritation is that asbestosis occurs in an organ of high mobility -- the lung -- and that a fibrous reaction can be produced by injection of asbestos fibres into the peritoneum, where there is also a de gree of mobility, but not in other extrapuimonary organs." Paragraph 90, Page 38 - Susceptibility to Tuberculous Infection ` `When the fibrous dust was being inhaled during the evolution of the infection, there was a spreading of the tuberculous pro cess for a time but usually the stimulus for continued pro liferation of the tubercle bacilli was not sustained, the pro gression was arrested and healing followed. Looking forward to the pleasure of seeing you on Thursday, Novem ber 11th, and with best wishes, I remain YMtNi. sincerely, exzuck cc M r. J. F . D. Rohrbach President