Document 8O5ZYxVZz045oD1kLkBp424wd

FILE NAME: ZZZ DATE: D DOC#: DOCUMENT DESCRIPTION:ZdZZZZZZ E .7,11,41111, :::; *: : Omcovt.ilv CUM"? ." 410 (_ HSTOS Group i Fitid Sales Force Hay 26, 1969 C, Voi c ,-_>. ASRESTO5 TOXICOLOGY REPORT Attached is the most recent Toxicology Report on Asbestos as issued by Union Carbide. The only major change is the notation regarding the change in thieshold limit value (TLV) from 5milLion_particies . psr cubic Coot of air(tucf).. tn_A-MItestablished by. 0!eDepartment of Labor undei the Walsh-Healy Act. This environmental safety restriction applies to concerns sit plying materials under government contract or involving public funds. It is almost certain that this standard trill be adopted by the AGM conference for all industry. These levelu of asbestos, dust concentration can be raached by proper care and equipment. The use of Calidria Asbestos proprietary pelletized products utii male everyone's job easier: V3Y/ds Attachment - Walter S. Y ung, Jr. UNION CARRiDE CORPORATION CI IEMICALS AND PLASTICS 270 PARK AVENUE. N Y.N il2U17 /.1..1.! 1' j /141OISCOVOIV CUM* 1 ,V;V:Idi.kl) ,,." .r ) ........--. . / . ' \I c . ( . L... ( 1 _Z ...,- . . Z-"cga, EA G 74. a 6 ASBESTOS TOXICOLOGY REPORT It has been known for years that some persons working in asbestos production were prone to develop a disabling lung disease. In time, this condition became known as asbestosis and was related to exposure to high concentrations of asbestos dust. With further experience, it was found that men could work with asbestos without development of Lung disease if dust concentrations were kept below a certain level. Et has been generally accepted that a worker will not develop asbestosis if he is exposed to no more than 5 million particles per cubic foot of air, even if this exposure continues for his entire working lifetime. Although no cases of asbestosis are known to have occurred when exposures have been maintained at or below this level, the ACGIii (which sets the threshuld Limit value (TLV) in the U. S. A.) has indicated they intend to lower the TLV for asbestos to 2 million particles pPr cubic foot in an effort to increase the satety factor incorporated in the limit. The U. S. Department of Labor has already issued a regulation under the Welsh-Healy Act placing the TLV for asbestos at 2 million particles per cubic foot for public contracts In which they have jurisdiction. This concentration of dust is generally not visible in the average work area unless a beam of tight causing a Tyndall effect is present. Usually the dust concentration must be from 8-10 million particles per cubic foot (MPPCF) before its presence is visible in average lighting conditions. Several years ago, it was reported that there was an increase in the incidence of cancerous tumors, especially of the lung, associated with asbestosis. Recently there have been 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 type of cancer named mesotheLtoma has been noted to be associated with asbestos exposure in recent years. These tumors, while rather few in number to date, may occur in individuals with histories of only slight expusnres, and chat as much as twenty to forty years earlier. There is considerable evidence that crocidolite is most frequently associated with mesotheliomas. From the data available it appears that the TLV of 5 MPPCF may not be low enough to protect against mesothelioma. Research on the problem continues. ANION CA111111)E EnflPfli1/1IION CHEMICALS ANI'l ntirlrli :In) AvrNur. N 1 ,N 114117 1 3 -2- Control of asbestos dust exposure is therefore 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 En the system are necessary. _Palletising is sometimes used to improve the handling characteristics of others:rat dusty materials. Where satisfactory containment to stay within the Threshold Limit Value is impractical or impossible, efficient and reliable respirators are available for the protection of the employee. A program of environmental monitoring is highly desirable to determine that Threshold Limit Values are not being exceeded. In manufacturing industries it would be desirable to know the dust concentrations where the asbestos is dumped from bags into the process. Concentrations should also be determined where dusting Occurs in 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 examination of workers are desirable. These should include chest X-rays to insure that the worker has no chest conditionOrior-tb-work-Ulth--iiiiiitBi-ind to determine that no lung changes are resulting from work with asbestos. It is believed that the addition of asbestos at the proposed levels during the manufacture of 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 concentrations 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. 5/8/69 Industrial Uedicine And Toxicology Department Union Carbide Corporation