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FILE NAME: Talc (TALC) DATE: 1972 Apr DOC#: TALC404 DOCUMENT DESCRIPTION: Notes on Seminar on Asbestos Supplementary Notes Supplied to the Attendees of the IITRI SEMINAR ON ASBESTOS April 4-7, 1972 IIT Research Institute 10 West 35th Street Chicago, Illinois 60616 f A c k : i) a Tue sday , Apr i1 4 th Chairman - Dr. Colin F. Harwood Morning 9:00 - 9:30 9:30 - 9 :40 9:40 - 11:00 11 :00 - 11:15 11:15 - 12:00 12:00 - 1:00 Afternoon 1:00 2:00 2:15 3:30 - 2:00 2:15 3:30 4:00 Regis tra tion Opening Welcome Introduction Coffee Break Introduction (cont'd) Lunch Dr. Harwood Dr. Harwood Medical Aspects Dr. Nicholson Coffee Break Medical Aspects (cont'd) Dr. Nicholson Questions and Speakers from Floor Wednesda y, April 5th Chairman - Dr. Colin F. Harwood Morning 9:00 - 10:15 10:15 - 10:30 10:30 - 11:30 11:30 - 12:00 12:00 - 1:00 Legal Aspects Coffee Break Legal Aspects (cont'd) Questions and Speakers from Floor > Lunch Mr. Tim Harker Mr. Tim Harker Afternoon ' 1:00 - 2:00 2:00 - 2:15 2:15 - 3:15 3:15 - 3:45 3:45 - 4:00 In-Plant Control Techniques Coffee Break In-Plant Concentration Levels Experience of Good and Bad Practice , Questions and Speakers from Floor Dr. Harwood Dr, Harwood Mr. Nathan Willens Thursclay,_Ap ri] 6th Cha irma n MT RpCr -- " - -- n> otti m o v v IITRI ASBESTOS SEMINAR AGENDA Page 2 Afternoon 1:00 - 1:45 1:45 - 2:15 2:15 - 2:30 2:30 - 3:30 3:30 - 4:00 Basis for the Occupa tional Exposure Levels Worker Protection Aspects Mr. Duncan Holaday Coffee Break Worker Protection Aspects (cont'd) Mr. Duncan Boladay Questions and Speakers from Floor Friday, April 7th Morning 9:00 - 10:00 10:00 - 10:15 10:15 - 11:45 11:45 - 12:00 Chairman - Dr. Colin F. Harwood Monitoring Theory Coffee Break Standard Methods of Moni toring Questions from Floor Mr. John Stockham Mr. John Stockham production),, Total US production (1969) was 125,936 tons, valued at an estimated $10,648,000 The United States utilizes about one-fourth of the world's production of asbestos, practically all of it is imported from Canada and Africa Figure 1 graphically illustrates domestic supply and consumption 3 ASBESTOS EMISSIONS 3 o1 Non-Industrial Sources Before entering into the main source of asbestos emissions, that is, through commercial manufacturers processes, it is worthwhile to consider briefly other less obvious but important mission sources These may be listed as: < Rock Outcrops Farming Construction Talcum Powder 3.11 Rock Outcrops It has been pointed out previously in Table 1 that asbestos containing rock outcrops in very many areas of the United States It is interesting to note that in 1920, Staten Island was once considered a large enough outcrop that mining on a commercial scale was undertaken there Emission from such outcrops will occur due to the natural eroding processes of earthquakes, temperature, wind,and rain. Thus,wind and water-borne erosion products will inevitably contain asbestos particles. 3o1 o2 Farming Farming of the soil in areas containing asbestos rock will cause the emission of fibers. Such actions as tilling of the soil are always dusty operations (unless, of course, it happens to be wet), the extent of the emissions will depend on IIT RESEARCH INSTITUTE 4 the concentration of aseesees in the soil. Studies have been conducted on the effect of such emis sions on the health of the local population(1). The evidence, though not very conclusive, suggested that asbestosis could be caused by agricultural employment., 3.1.3 Construction The outcrops of asbestos-containing rock will give rise to emissions whenever construction is undertaken. Hence, such activity as excavating for housing, pipe laying, and road making, must be considered as a source. 3.1.4 Talcum ,,Powders Talcum powder is a mineral rock dust very closely related mineralogically to asbestos. The main difference lies in the fact that talcum powder has a platy morphology, while asbestos is characterized by its fibrous nature. The fact that talc 'is very frequently found with a signi ficant fibrous content; now leads to a very important situation since the total quantities of talc mined in the u.S. exceeds that of asbestos. , . It was pointed out by Craliey(2) that the majority of cos metic talcs contain significant, quantities of fibrous particles. Virtually everybody, from babies up, is exposed to cosmetic talc and so are exposed to the threat of asbestos bodies. Apart from the cosmetic use, talc is used very consider ably in industry as, for example, a filler and as a lubricant in the production of pharmaceutical tablets and rubber goods. Another large use is as a carrier for pesticides in the spraying of crops. On a more exotic note, there has been recent publications on the use of talcum for polishing r i c e (3,4) and its association stomach cancer because of its asbestos content. Even more NT RESEARCH INSTITUTE 6 er.icen may be endangered by ,.r.e' balloons. i i ;ssiGPi on La.i.c fias ,00011 included for com ole~ eoess ir. tins repor t concet nine a see stos . Certainly it should not be; neglected when considering the health effects and hazard of asbestos fibers. Other studies discussing the presence of asbestiform fibers in the mining of talc are those of Siegel(5) and of Greenberg(6) 3 -2 Manufacturing Processes 32.1 Introduction Several tasks preliminary to the manufacture of asbestos products are potential emission sources. These are common to all asbestos processing. They include such functions as un loading and storage of milled asbestos, subsequent transport of the bagged asbestos to the bag opening area, fluffing of the compacted fibers, and a mixing process \vliere asbestos fibers are dry mixed with other materials. The bagged asbestos is usually unloaded from railway box cars, moved to storage areas, and finally transported to bag opening areas by fcprk-lj ft trucks, opportunities exist, during each of these operations for bags to become damaged and spill fibers to the atmosphere. The amount of emission from the bag opening and dumping processes depend upon the degree to which the tasks are enclosed, in some instances, the bags are cut open with sharp knives and the contents dumped into a container or onto a conveyor belt. The compacted fibers, from packing at the mill, are fed through a "willow" or "Moody f.buffer" which fluffs up and separates the fibers. This operation may also be employed as a blending stage wherein several grades of fibers are thoroughly mixed. NT RESEARCH INSTITUTE 7