Document jmvV5j5KJwnGqX5LKqN4ORJn9

FILE NAME: Union Carbide (UC) DATE: 1965 Jan 12 DOC#: UC166 DOCUMENT DESCRIPTION: Internal Memo, Nuclear Division - Asbestos Toxicology Report UNION CARBIDE CORPORATION Nuclear Division New York, N. Y. MEMORANDUM To : Messrs T. Dougherty R. A. Miller R. Stobaeus T; R. van Fleet . UISIRIBUTION W. T. Cohan p J. A. Riddle r - VV, Haskj L f C. Brice t'- -Kamens f ] A. West [~j :'S. Vessels Q , fSh-h*# ,g.r / 1 January 1& & 965^ cc: Messrs K. W. Lentz A. E. Pufahl G. S. Jordan H. F. Reichard N. J, Setter R. G. Woolery {/J * A. Ricci Dr. C. U. Dernehl Subj ect: ASBESTOS TOXICOLOGY REPORT Gentlemen: t Recently several reports were given t. technical meetings and summaries oi them carried by fcne national wire services concerning possible carcinogenic properties of asbestos. Some or you may have received cuestions from your customers on this subject. \ In order to counteract any serious problems or worries before they get out of hand, we have asked Dr. C. U. Dernehl, Director' of Toxicology, bnion Caroide Corporation, to r o murate a statement tor us. a cony' of his statement is enclosed. Additional copies can be obtained from me or you may make your own copies if you wish to pass them on to interested customers. You Will ,.obe i.udt, in. essence, the report states tact good housekccoinc --such as would be required in any dust-producing operation -- should be sufficient to prevent any problem with asoestosis. You will also note that he mentions use in a wet system -- which certainly applies to the paper and a pellet form -- one of the strong points of our asbestos -- as additional means of minimizing any potential problem with the product. rurtaer, other asbestos producers and those acquainted with the subject feel that the original data upon whicn the cancer-producing report was based did not take into account any outside influences, such as smoking or corrosive atmospheres, which also might produce cancer. Here, it should be noted that much asbestos usage considered in the technical papers is in conjunction with tar and pitch compounds which are known to contain carcinogenic materials. UCC 020782 - 2- You should have this statement available for any questions which might arise from your customers. If appropriate in your judgment, perhaps it should be discussed with certain customers who have not yet raised the subject. I do not feel we should make a big issue of it thereby drawing unnecessary attention to the subject since the conclusions are still questionable. If you have any questions, please discuss them with me. T.J.Hall/dk enc. UCC 020783 :.h'i UNION CARBIDE CORPORATION 2 7 0 P A R K A V E N U E , N E W YO RK , ,N. Y, 10017 ASBESTOS TOXICOLOGY REPORT It nas been known or ranny years chnc solig persons working in asbestos production were prone to develop a disabling lung disease. In time, this condition become known &s asbestosis and was related to ex posure to high concentrations of asbestos dust, with further experience, it was found tnat men could work with asoestos without development of lung disease if dust concentrations were i-ceo ; below a certain level. It is now generally accepted that a tan can work a 40-hour week for a life time without developing asbc.c... if tv., at' vaot c ,;t ; -.rticle count is kept at or below 5 million parcicl; concentration of 5 million particle per cur: foot ci air. This dust Aper ___ _o_u__t__ci _a_ir is cha Threshold Limit Value for asbestos, and no cases of asbestosis known, to have occurred when exposures nave bean maintained at or below this level, despite large-scale utilization (now approaching one million tons per year in .he U.S.A.). This concentration ox dust is general!''' not visible in the average work area uniess a beam of light causing a Tyndall effect is present. Usually tne dust concentration must be from 1-10 million particles per cubic foot before its presence is visible in aver age lighting conditions. * deveral years ago, it was reported that there was an increase in the incidence of cancerous tumors, especially of the lung, associated with ashestosis.. 'Recently there rave oeen reports of some cancers occurring in individuals exposed to asbestos dust, but who have not developed clinical asbestosis. It Is believed by most authorities that these cases have been associated with exposures significantly exceeding the Threshold Limit Value. A. major manufacturer of asbestos products who also mines asbestos has not been able to show an increase in cancerous growtns *n men working where dust concentrations were maintained at the Threshold Limit Value. . Control of asbestos oust exposure as tnererore necessary. The control methods are the standard ones applicable to a variety of dusty operations.. They include closed flow systems, wet processes where possible, and adequate exhaust ventilation where openings ir. the system are necessary. Pelletizing is sometimes used to improve the handling characteristics of otherwise dusty materials. Where satisfactory con tainment to stay within the Threshold Limit Value is impractical or impossible, efficient and reliable respirators are available for rhe protection of the employee. A program of environmental monitoring is highly desirable to determine that Threshold Limit Values are notbein^ exceeded. In paper manufacturing, it would be desirable to know the dCst concentrations where the asbestos is dumped from bags into the pulp Blurry. Concentrations should also be determined where dusting occurs in UCC 020784 - 2- finishing products. While initial dust determinations should be made at frequent intervals, once the level has been established as satisfactory, the frequency may be extended to occasional tests to assure continuation of a satisfactory condition. Pre-employment and periodic physical examinations of workers are desirable. These should include chest X-rays to insure that the worker has no chest condition prior to work with asbestos and to determine that no lung changea are resulting from work with asbestos. It is believed that the addition of asbestos at the proposed levels during the manufacture of paper products would be harmless to the consumer. Total dusting would have to be well in excess of any levels acceptable to the consumer for the asbestos concentration to approach the Threshold Limit Value. In conclusion, while asbestos dust in excess of the Threshold Limit Value is potentially harmful, as are many other dusts encountered in industry, it is as readily controlled as other such dusts and it can be used safely with appropriate precautions. Carl U. Dernehl, M.D, Director of Toxicology X. S. Lane, M.D. Assistant Director of Toxicology UCC 020785