Document jy8edXvZJzOO44x1pVK6o73xN

'f. ft &asbey & Mjxttisox Com .rkfexmtiSU October 28, 1948 Confidential Mr. Vandiver Brown Jofans-Manville Corporation 22 2ist New York 16,"n. Y. Dear Mr. Brown: Sarcnas Laboratory Report on Asbestos Port 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 aiso copy at year comments on the report which we briefly discussed over the telephone the other day. In addition, I wish to thank you lor your letter of October 27th and lor the kind Invitation to be present at a luncheon in the johas-MaavUle Corporation Board room on Thursday, November 11th, at 12:30 P.M. I accent 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 la your memorandum sent with your letter of October 22nd. 2. The report is confidential and is the property at those who ad vanced the funds for carrying out the experiments it the Saranac Laboratory. 3. The report should be confined to the results on animal a only. 4. There should be a separate later report, not a supplementary report, dealing with >mma ashestnets. 6. Experiments reported on to date covering tumors and r"*"mnia caused by asbestos dust are inconclusive. The entire paragraph No. 92 an page 39 "Neoplasm" should be deleted. 6. The of minion asbestoe particles (long end short) per cub! loot of air is. In my opiates, a more accurate and indicative measureme than the percentage otf long fibres. Mr. Vandiver Brown Oetoc^r 23, 1348 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. "Willi quarts dust It has bees demonstrated that the smaller the particles, the more intense Is the tissue reaction, and that there is little reaction to particles larger than three micron* In diameter. Is the case d asbestos, nowever. the reverse is true and apparently only long fibres have any specific effect." Paragraph 87, Page 37 - Theory of irritant Action of Asbestos Minerals "In view of this evidence It seems more likely that asbestosis is caused by an unusual mechanical Irritation from long asbes tos fibres." "Further support for toe 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 eztrapxiaonary organs." Paragraph 90, Page 38 - Susceptibility to Tuberculous Infection "When the fibrous dust was being inhaled during the evclutloc of the Infection, there was a spreading of the tuberculous pro cess for a time but usually the stimulus far continued pro liferation of the tubercle bacilli was not sustained, the pro gression was arrested and healing followed. t rt^iriTiy forward to the pleasure of seeing you on Thursday, Novem ber 11th, and with best wishes, Z remain esuck ec Ur. J. F- D. Rohrbach President