Document ba610JYpjGGzLX96nM76Nz3z6

i Plasties Department Commercial Resina Division Experimental Station RECEIVED ; 1966 HASKELL LABORATORY C-OOdST/. ee: H. L. Cats*, Jr. J. W. Clayton,Jr. R. C. Doban B. N. Epstein E. H. Price 2. H. Tan EyeVc Pile: 33A - 323 - Haskell - D Bide. - 323 - 323 - WWL November 7, 1966 -JO: J. F. MOROAN Employaa Relations Department, Haskall Lab FROM: R. A. DARBY L foXlCITY OP ASBESTOS Wa eartalnly appreciated your visit on November 3 to discuss health problems associated with the use of asbestos. In accord with your reconsendatlons, we are proceeding as follows: 1. Work with any type asbestos has bean haltad until we have obtained approved face masks (recomended by the Bureau of Mines) for filtering asbestos dust. / 2. Haskall Laboratory will be invited to observe our aemlworks operations whereby asbestos will be extrusion compounded At the moment we do not have a firm date for this, partly because the approved masks are not In hand. 3. In view of your comments, we will not purchase or work with the croeodollte form of asbestos pending further classi fication of this material. As I understand It, this form of asbestos contains measurable amounts of benzpyrene, a carcinogen, and the incidence of caneer In South African miners has been related to exposure to croeodollte. The major fora of asbestos, chrysctlle, apparently Is much safer than croeodollte In this respect. We would appreciate your opinion of the hazards of anthophylllte asbestos, which is supplied by the Blue Rock Mining Corporation. >- 4. Haskell Laboratory will keep us Informed of future developments In thsir study of the toxicology of asbestos. Por example, the investigation of an Instrument(Impinger) to measure dust concentration may be a significant benefit to us and other groups working with such materials as asbestos or glass. I gathered from your comments that dust levels below 5 MM particlsa/ft* UoS DUP 0900683 J. P. Morgan 2 November 7, 1966 are generally safe for chrysotlle asbestos, while concentrations of glass dust less than 20 MM partlc.les/fts are not harmful. (A reference value of 0.5 MM partielee/ft* for an office or similar * room may be helpful in appreciating the levels mentioned above.) In recalling our discussion, X believe you mentioned that asbestosis, which is the formation of nodules around asbestos fibers accumulated in the lung, results from continuous exposure to asbestos dust for long periods of time, and la aimilar to sillcosls. Asbestosis can lead to cancer in the lower lobes of the lung. Mesothelioma is the formation of malignant tuaora in the layer of tissue called the mesothella, and usually occurs in the plural cavity, although tumors have been lcnown to develop in the same stratum of tlasua elsawhere in the body. Your guidance in the proper handling of asbestos, glass and related fillers for plastics will be greatly appreciated. This area of research has considerable business potential and while we do not want to inhibit ourselves unnecessarily, we want to make sure that our operations are consistent with the latest medical knowledge. sdo DUP 0900684