Document GyrMKMXad6NOEYMM9RQRdxDn

Council Currents July!August 1989 - C l-a/V3o~- j '^c'Vv\ Page 7 \HERA Headlines X Analysis Warning to TEM Laboratories In preparing for a surface dust sampling project, McCrone Environ mental Services, Inc. discovered a problem with preparing Nuclepore brand "Membra-Fil" 0.22(1 pore size mixed cellulose ester (MCE) filters, stock number 140628 (25 mm diameter) and 141128 (47 mm diameter). The samples were to be analyzed using an indirect prep procedure that required filtering a water-based solution through these filters and dissolving the filter material on acetone Jaffe wicks, as per the standard NIOSH 7402 prepara tion method for MCE filters used for air sampling. The filters would not dissolve with acetone even though the literature accompanying the filters indicated acetone as an acceptable dissolving agent. A call to Nuclepore revealed that the '.2p pore size MCEs, which are often used for water samples, are not manufac tured in the same manner as die 0.45p pore size MCE filters that are marketed for air samples. To facilitate water filtration the 0.22s are treated with a wetting agent, which prevents clearing on acetone wicks. Nuclepore provides some guidance to laboratories that may use MCE filters for other applications: MCE filters marked "MF' are surfactant-treated, whereas those labeled "MR" are untreated and should easily dissolve with acetone. However, all of the 0.22pm MCE filters available at this time from Nuclepore contain the wetting agent. McCrone's follow-up research proved that dimethyl formamide (DMF) success fully dissolves the Nuclepore 0.22p pore size Membra-Fil filters. By Joseph A. Krewer and Harriotte A. Hurley, CIH, McCrone Environmental Services, Inc. Global Outlook (WHO Convenes Group of Experts to Recommend Occupational Exposure Limit for Asbestos experimental evidence, lung burden analysis and epidemiological evidence of dose-response relations. Based on this review, die experts could not state definitively (hat there is a level of exposure to asbestos below which there is no risk. Yet they were of the opinion that a level of control can be achieved at which the lifetime risks of lung cancer or mesothelioma are non-existent or are so small that they could only be detected by a very large study. The group then prepared a list of recommendations to the WHO, which included the following: Per chrysctile asbestos, on the basis of health, it is recommended that the Occupational Exposure Limit (OEL) for an individual worker should be 1 fiber/ml eight-hour time weighted average (TWA). It is, however, appropriate for those countries which have not yet set an OEL to set it initially at 2 fibers/ml eight-hour TWA, with die intent that it should be further lowered as soon as practical. For crocidolite and Amosite asbestos, on the basis of health, it is recom mended that the OEL should be zero. It is, however, appropriate for the government authorities to permit use of crocidolite and Amosite for special purposes, when replacement is not reasonably practical, provided that steps are taken to ensure that the health of workers and users of the products is not placed at risk. On April 10-11,1989, a Group of Experts Meeting was convened in Oxford, England, by the World Health Organization (WHO) to review and update the present scientific information regarding the relative risks associated with specific exposure levels for asbes tos, in order to identify die efficacy of recommending an occupational exposure limit. The meeting was organized because it was felt that many countries in the devel- ~ung world needed guidance on setting xupational exposure limits for asbestos in order to comply with the international labor standards set out in the Interna tional Labour Office Convention 162, Safety in the Use of Asbestos. The meeting was chaired by Sir Richard Doll, an epidemiologist at the University of Oxford, and included experts from the United Kingdom, die United States, Canada, Japan, France, die Soviet Union, Sweden, Turkey, Brazil, Nigeria, China, Malaysia and Finland. Representatives from ribn-govemmental organizations, such as the Interna tional Federation of Chemical, Energy and General Worker's Unions (1CEF), and various WHO collaborating centers and programs also participated in the consultation meeting. Two background documents had been prepared prior to die consultation meeting, and extensive review was made of the most recent data from animal The Group of Experts Meeting in Oxford may impact the asbestos-in buildings issue in two respects. First, it brings up the issue of distinguishing between chrysotile and amphibole groups of fibers for regulatory purposes. Second, it supports recommendations from EPA that universal removal pro grams of friable insulation materials are not always warranted. Provided the materials are in good condition and not easily disturbed, managing the asbestos is a viable alternative to removal. Managing the asbestos includes conduct ing training, implementing an operations and maintenance program, and removing the asbestos at the time of renovation or demolition. HWBUI0003967 'ge8 Council Currents July!August 1989 mo... (continuedfrom page 7) ments should cottact the Asbestos Institute, 1130 Shetbrooke St W., Suite 410, Montreal, Quebec, Canada H3A should prepare and adopt, as early as possible, a "Code of Practice" on Safety in the Use of Insulation Wools. A The full report accompanied by the two background documents is expected 2M8; (514) 844-3956; fax (514) 8441381. convention on Safety in die Use of Mineral and Synthetic Fibers was to be available sometime this summer. Those interested in copies of the docu- By Scon Houston, The Asbestos Institute, Canada considered premature in view of the lack of knowledge on many of these fibers. Experts did agree, however, that where knowledge is insufficient, preventive and Global Outlook control measures should be implemented, on a temporary basis, with the under ILO Conducts Meeting on Safety in the standing that tire adequacy of these measures be reviewed when new information is available. The control Use of Mineral and Synthetic Fibers measures considered by the group of experts follow closely those outlined in From April 17-25,1989, the Interna tional Labour Office (ILO) in Geneva presided over a meeting of experts who studied the question of preventive and protective measures related to the occupational health risks due to exposure to fibers, whether natural or artificial, other than asbestos. Fifteen experts were invited to the meeting. They represented various gov ernments, and the employers' and workers' groups of the Governing Body of ILO. Several observers and advisors also attended the meeting, representing the World Health Organization, the Commis sion of European Communities, die International Organization of Employers, the International Confederation of Free Trade Unions and various other labor and employer organizations. The participants were invited to review a working document that covered demiological evidence. Reference was also made to evaluations made by die International Agency for Research on Cancer (IARC), which has classified glass wool and special purpose fibers, ceramic fibers, rock wool and slag wool, as class 2 B carcinogens--possibly carcinogenic to man. With regard to synthetic organic fibers, the experts expressed their reservation on the validity of the assess ment of the health effects of these materials, as no evaluation was available by the IARC. The experts agreed that there was evidence that, at high concen trations, certain aramid fibers could cause fibrosis and lung tumors in animal inhalation studies. No similar studies had been reported for other synthetic organic fibers. Following the review of the working document, the experts produced a report that included their conclusions and the Code of Practice on Asbestos, published by the ILO in 1984. The Geneva meeting confirmed growing scientific opinion that long, thin, durable fibers are the most hazardous, and that in all cases, die objective should be the reduction of exposure to airborne respirable fibers. These findings have important implications for building owners confronted with material replace ment decisions. Many of today's prod ucts contain man-made mineral fibers which can create respirable dust during installation, repair and removal activities. Regulations appear eminent for these materials. Consequently building owners, when choosing replacement materials, must ensure that they improve their situation and not put themselves in the position of having to make the same decision five to 10 years from now as they are facing today with friable asbestos insulation products. tiie general characteristics and manufac turing methods of man-made mineral and recommendations. Among those was an urgent recommendation that the ILO By Scott Houston, The Asbestos Institute. Canada synthetic fibers, the occupational and non-occupational exposures, die health Training Notes--------------------- effects and their evaluation with regard to human risks, the monitoring of airborne dust, die preventive and control meas NDAA Listings Available at ures, and die laws and practices in selected countries. Special emphasis was given to glass Reduced Rates wool, rock wool and slag wool, as well as The National Database of AHERA compiles that information into report to some more recently developed Accreditation is working. The first two form for local education agencies, ynthetic materials, such as refractory sales of customized listings were sold in building owners and managers, and other iceramic) fibers and aramid fibers. They mid-June just before the beginning of a interested parties. noted that the possibility for harmful full-throttle marketing blitz. The data A brochure fully explaining tire effects on the health of workers exposed base, funded by an EPA grant, gathers program and a press release campaign to to these fibers was supported by results skill and demographic information from enhance visibility in die asbestos controL ; of animal experiments and some epi AHERA-discipline trained workers and related and schools-oriented media is || HWBUI0003968