While asbestos has been called a 'miracle substance' because of its unique properties, asbestos has also caused cancer in those exposed to its indestructible fibres. This mix of benefits and costs has made the regulation of asbestos particularly difficult for policymakers; in both countries, regulation has been characterized by exceptional measures. In Canada, regulating asbestos has led to innumerable government studies, including the Ontario Royal Commission on Matters of Health and Safety Arising from the Use of Asbestos (1984). The Commission's Report was unique in its extensive scope and detail. Its three volume report included a detailed treatment of asbestos-related diseases, quantitative risk estimates, and assessments of current regulations. The regulatory history of asbestos in the US was also somewhat exceptional. It involved a protracted battle between the Environmental Protection Agency and the Office of Management and Budget. Out of this battle came a House Subcommittee investigation into OMB interference in EPA rulemaking (1985). The comprehensiveness of the Royal Commission's Report is highly significant given that detailed scientific explanations of policy, and the criteria used to balance costs and benefits are usually not explicitly revealed by Canadian regulators. In this sense, the somewhat anomalous nature of the Commission's Report offers an especially detailed view of regulating hazardous substances in Canada. Like the Royal Commission Report, the House investigation provides an extraordinarily detailed look at the politics of regulating a hazardous substance. Out of these involved deliberations, though, emerge very different policies on asbestos. While the US has implemented a three-stage ban, Canadian regulators view asbestos primarily as an occupational problem. The workplace standards of the US, Ontario and Quebec differ, with the US being more stringent. The contributions of this paper stem from its balanced consideration of scientific and political determinants and its comparative nature. This balanced consideration illustrates the double impact of science. While science can set the boundaries of a policy debate, uncertain areas of scientific evidence are usually politicized by competing interests. Thus, the less science is certain, the more politics matters. Within the boundaries set by science, various political forces have an impact on the policy process. Policies are shown to emerge from very different interrelationships between state structures and societal actors, influenced by varying degrees of economic dependence on asbestos. Group theory alone fails to explain the divergent policy outcomes; so do neo-Marxist and institutionalist approaches. Thus, this study demonstrates the superiority of integrative approaches, as opposed to those which emphasize one causal variable at the expense of others. / Arts, Faculty of / Political Science, Department of / Graduate

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International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The White Sands Telemetry Data Center (TDC) is moving to a new home. The TDC, along with various range functions, is moving to the new J. W. Cox Range Control Center (CRCC). The CRCC is under construction and will replace the present control center. Construction of the new CRCC and the resulting move was prompted by the presence of asbestos in the present Range Control Center (RCC). The CRCC construction will be completed in September 1999 at which time the communications backbone will be installed. (Estimated time to complete the installation is nine months.) In early 2000, White Sands will begin transition of the TDC and other commodity functions to the CRCC. The transition must not interrupt normal support to range customers and will result in the consolidation of all range control functions. The new CRCC was designed to meet current and future mission requirements and will contain the latest in backbone network design and functionality for the range customer. The CRCC is the single point of control for all missions conducted on the 3700 square mile range. The Telemetry Data Center will be moved in two parts into the new CRCC. This will allow us to run parallel operations with the old RCC until the CRCC is proven reliable and minimize overall downtime. Associated telemetry fiber optics, microwave communications and field data relay sites will be upgraded and moved at the same time. Since the TDC is so tightly dependent upon data input from both fiber optics and microwave communications inputs, a cohesive move is critical to the overall success of the transition. This paper also provides an overview of the CRCC design, commodity transition, and lessons learned.

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Our research purpose is to build up new and efficient methods to quantitate amounts of air-borne asbestos. A basic idea behind the methods is the use of a FT-IR instrument to measure the asbestos absorbances. Karen McCune, an ex-coworker in our group, developed three procedures to eliminate background absorbances from the filters on which the asbestos is collected. These procedures included the spectral subtraction, the chemical digestion, and the ashing of cellulose ester filters.My research has ultilized and expanded on the ashing procedure. First, the detection limits and linearity of the aforementioned transmission method were determined. Using amosite asbestos, we developed a standard curve from 40 tg to 2 µg which agreed well with Beer's Law. We determined that the detection limit of this method resulted from minutely contaminated salt and not from instrumental limitations. Even using highly pure KBr, CsCl, or KC1, similar detection limits were obtained.Second, the use of diffuse reflection to measure the asbestos absorbances was investigated. The method, much simpler than the transmission technique, consists of pouring the recovered asbestos-salt mixture into a small cup and obtaining the diffuse reflectance spectrum using a special accessory. A standard curve of amosite ranging from 40 p.g to 1 .tg was produced. One important observation was that when KCl adsorbed water from the air while a background spectrum was collected, the water absorption band contributed negatively to the area under the Si-O stretching region. This contribution prohibits the detection of smaller amounts of amosite. A standard curve of chrysotile asbestos ranging from 40 µg to 5 µg was also produced.Another goal of our research is to investigate the quantitation and identification capabilities when asbestos is present as mixtures of amosite, chrysotile, or other closely related silicates such as, kaolin. In conjunction with the diffuse reflection method, a curve fitting program was used to analyze the amount of each component in a mixture. First mixtures of amosite and chrysotile were studied. Then mixtures of amosite, chrysotile, and kaolin, mixtures which resemble the real world's environment, were studied.Overall, the FT-IR spectroscopic methods are more efficient and applicable than the traditional fiber-counting methods. Our methods not only objectively quantitate the amount of asbestos but also identify the type. / Department of Chemistry

A dissertation submitted to the Faculty of Medicine, University of the Witwatersrand, Johannesburg, for the degree of Master of Science (Medicine). / Objective: To determine the relationship between asbestos exposure and chromosome damage, as depicted by sister chromatid exchange frequency. Design: Descriptive, cross-sectional study. Setting: Asbestos-products factory Subjects: 31 asbestos-exposed subjects and 21 unexposed subjects Main outcome measure: Mean sister chromatid exchange (SCE) frequency per metaphase cell. Results: The control group had a slightly higher mean SCE frequency per cell than the exposed group (3.4%) but this difference was not statistically significant (p = 0.5935). Smoking contributed significantly to SCE frequencies in both the exposed and unexposed groups. The mean SCE frequencies per cell in the exposed group were 10.49 for smokers and 8.59 for non-smokers (p = 0.0078). The frequencies for smokers and non-smokers in the unexposed group were 10.83 and 8.58, respectively (p = 0.0257). Conclusions: The failure to observe an increase in SCE frequency does not rule out asbestos exposure as a genotoxic agent. Rather, it may help to resolve the limitations of this method for detecting genetic damage. Alternatively, the fibre levels to which this group was exposed may have been too low to cause chromosome damage. / WHSLYP2016

Faculty of Health Sciences, Master of Science in Medicine in the field of Epidemiology and Biostatistics, 9502650w / An autopsy-based case-series of South African miners was used to evaluate the evidence required to attribute a miner’s lung cancer to occupational asbestos exposure for compensation. The slightly different Helsinki (1997) and National Institute for Occupational Health (NIOH) criteria (1988) require that one of four factors (asbestosis, occupational exposure, raised burden of asbestos fibres and/or bodies) be fulfilled for attribution. These criteria were applied to the case-series to determine and compare the proportions of NIOH- and Helsinki-attributable lung cancers. Of 195 lung cancer cases, 47% (91) were Helsinki-attributable and 52% (101) NIOH-attributable: with 72% concordance. Some differences in the details of occupational exposure criteria and methods for assessing the burden of asbestos in the lung were responsible for differences in these proportions. If attribution had taken place using only presence of asbestosis and the occupational exposure history, many cases would not have been attributable to asbestos. Therefore, taking into account burden of asbestos in lung tissue was important. However, it was found that phase contrast microscopy (PCM) for counting asbestos bodies was “sufficient” and that scanning electron microscopy (SEM), advocated by the Helsinki criteria, added <1% of the cases, suggesting that the cost of expensive SEM fibre counts in a developing country may outweigh the benefits. Using the Helsinki criteria as the gold standard, the sensitivity of the NIOH criteria was 75.8% (95% CI: 65.7 – 84.2).

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