Document 3J60noxLDrrLnQ2Emr0LJ1dDy

June 2, 1965 , Ref. 609 Mr. H. Junes Bigalox? 0x70ns-Corning Fibcrglas Corporation General Offices Toledo 1, Ohio Bear Mr. Bigaloxv: < ' Wo are av:are of the controvcrsazy created by Dr. J. Sclikoff on asbestos hygiene. There are fortunately how ever , several professional and comprehensive studies in progress which well determine what the asbestos health hazards are and how to solve then. The U. 5. Department of Health, Education and Wel fare in 1962 started an ''Occupational Health Study of the Asbestos Products Industry." This study covers as bestos textile, brake linings, asbestos cement and thermal insulations. I would as suae your Mr. Taylor knoxvs about the insulation part of this study. Enclosed are two offi cial publications of the Department of Health, Education and Xtelfare related to the study and the asbestos textile industry. Wa would be glad to keep you advised on addi tional information if you wish. There was a conference on "The Biological Effect of Asbestos" in New York City on October 19-21, 1964. A copy of the program is enclosed along with abstracts of Selikoff's papers. You could request copies of all the artic.es from the New York Academy of Sciences. We have not received the information as yet. A report titled "An Epidemiological Study of Lung Cancer In Asbestos (Chrysotile) Miners" (Thetford Mines - 01 023 0733Black Lake) by D, C. Braun, M. D. and T. D, Truan, M.A PLAINTIFF'S EXHIBIT a/i/- UNTIFFS EXHIBIT I* ..$5036*co * -- il. J* Eigalow 2 June 2, 1965 fished in the AHA Archives of Industrial Health, Vol 17 - June, 1950. It concludes in part "...that the acbOS'b e miners in the Province of Quebec do not have a oantly higher death rate fren lung cancer than do bio segments of the general populations." A copy resort is enclosed. tJ" e cc y c D aA 1 r*\ rh ** is also important to note that Asbestos (Chryeoi-- ocidolite) are approved as a "Filler in Rubber Products used for food handling equipment." A s information is available from the Food and .etration Department of Health, Education and . the Federal Register, Saturday, October 14, :c 9715. Listed below is some additional information on: 1. Maximum dust levels 2. Particle sire 3. Dust level measurement 4. Respirators 1. Maximum Dust Level Permitted In Different States, Industries, or References Most of the states have adopted the linit recommended by the American Conference of Government, Industrial Hygienist, a quasi official group which has assumed leadership in establishing safe limits for many of the air contaminants. The A.C.G.I.H. limit for asbestos dust is 5 million particles per cubic foot of air for 3 hour, continuous, daily exposure. This limit applies to samples collected with the Greenberg-Smith impingcr or by a comparable method and counted by light field microscopy. 4 A complete discussion of duct sample collection and evaluation is given in "Industrial Dust" by Drinker ana Hatch published by McGraw Hill, and in "Industrial Hygiene and Toxicology", Vol. I, published by Inter science Publishers, New York. 2 Data And References on Critical Particle Size There is some controversy over the relative dangers of 01 023 0734 Mr. H. Janes Eigalow 3 June 2, 1063 2. Pat?-, And References Cn Cirtical Particle Size (cont.) snail particles (short fibers under 3 nacrous in length) and long fibers of 10 microns or core. Long fibers nay provoke a fibrous reaction in lung tissue somewhat core than short fibers. Cut long fibers in the air have a lesser chance of getting down deeply in the lung be cause of entrappeent in the uppei resipratory system. So the relative clanger of snail and large particles tend to balance out. A comprehensive discussion of dust particle size and its significance is given in "Puluinary Deposition and Retention of Inhaled Aero sols" by Match and Gross, Academic Press, New York, 1964. 3. Recommendation on How to Measure Dust Level, Equipment, and Procedure______________________________ Although the original Greenberg-Smith impinger method of dust sampling is recognized as standard, it has been shown that sampling with properly calibrated midget inpingers, portable elcctro-static precipitators and mem brane (Uillipore) filters will give comparable results. The important part of the dust measurement is the count ing cell. Counting is an exacting and tedious procedure. 4. Mask and Filler Recommendation Any respirator and filter combination approved by the U. S. Bureau of Mines for protection against pneumo coniosis producing dust will provide satisfactory pro tection. The respirator should be fitted carefully to each individual. If one brand does not fit snuggly another should be tried. The leading manufacturers of respiratory protcctice equipment are Mine Safety Appliance Company, American Optical Company, and Wil son Products. Attached is a copy of a guide on As bestos published by the American Industrial Hygiene Association. I will try to obtain the information you requested on the percent of fines that is fifty microns or longer. EAFiada Very truly yours, 01 023 0735 E. A. Farrell