Document Z49od2yoJJwMKMjQ5mmX2w3NV

The Saranac Laboratory FOR THE STUDY OF TUBERCULOSIS OF THE EDWARD L. TRUDEAU FOUNDATION Saranac Lake, N.Y. (COPY) April 11, 1946 PLAINTIFF'S EXHIBIT 0W9-6P Mr. Edward C. Anes Owens-Coming Fi'oerglas Corporation Toledo, Ohio Re: Leached Superfine Fiber Dear Mr. Ames: We have submitted the leached superfine fiber that you sent us to the sane treatment previously reported for the "D" yarn fabric. As night be expected, the new material, being composed of finer fiber, broke up into much smaller fragments, but again the process of treat ment did not create a dust cloud comparable to that obtained when crysotlle asbestos was handled in the same manner. One would Infer that if industrial processes were such that superfine fiber were subject to the proper manipula tion, a bust composed of particles small enough to be Inhaled would be crested. Whether these fibers have suffi cient flexibility to penetrate the respiratory passages still remains a question. Msny of them are about one micron in diameter and none were found over four microns in thick ness. Usually, when they broke into lengths under ten microns, the fragments were straight and never curved. Ey contrast, the still thinner asbestos fiber in these lengths is often curved. I know of no way to be absolutely sure whether this material is inhalable except by actual test in animals. This would necessitate using relatively large amounts of material and would involve experiments over periods of months. To satisfy my own curiosity, I an having some of the materi al injected into the tracheas of guinea pigs to observe the effect. I feel quite certain that, under the circumstances, we will produce an effect comparable to that produced by as bestos. Such a test, hovrever, will not give you the information that you need on inhalabllity. In view of these considerations, I can only say that I believe this latest form of fiber is more likely to cause pulmonary damage than any which you have previously sent us. I shall check the potentialities of the fiber to cause fibrosis by injecting into the lung under highly artificial conditions. I am not sure whether the fiber is Inhalable. 501 1606 (COPY) Page 2. Mr. Edward C. Ames Owens-Cornlng Fiberglas Corporation Re: Leached Superfine Fiber Incidentally, our X-ray department reports that they have received no films from any of your plants during the current year. I would be Interested to know whether this is merely the result of chance or whether you anticipate that more will be submitted later. My reason for asking Is a necessity for arranging the work of this department. It has personnel and facilities for doing a limited number of examinations a year and I have had to turn down requests for routine interpretations that might involve more films than could be handled. If you are not likely to need as much of our time as you have in the past, I shall take on one or more other industries who have asked for such service. Sincerely yours, LUG:LB H Leroy U. Gardner Director 01 501 1607