Canadian asbestos

World Symposium on Asbestos, Montreal, Canada, May 25—27, 1982. Canadian Asbestos Information Center, Montreal, Canada. 

Canadian asbestos WeiCasbest, Chrysotil whole-body exposure GanzkOrperbestrahlung whole mount Totalpraparat whole mount plastination Ganzkbrperplastination wick Docht... 

The evolution in the world production of asbestos fibers since 1950 is illustrated in Table 5 (5) after a peak near 1980, production leveled off after 1985 at 4.2 4.3 X 10 t. Changes in the production of the two main producers, Canada and the former USSR, over the same period are also illustrated. These figures show a substantial decrease in the Canadian production with a concomitant increase in the former USSR production. During recent years, several other countries, namely Brazil, Zimbabwe, and China, have substantially increased their production of chrysotile. Most of China s production, as well as the limited production of many other countries, is used in local industrial appHcations. South Africa is the only country where the three main types of asbestos are produced (chrysotile, crocidoHte, and amosite), and the only significant producer of amphibole fibers. 

The difficulties of adequate and reproducible diagnosis have interfered with determination of the incidence of mesothelioma. McDonald studied 11,000 Canadian chrysotile miners and, in 1980, reported that of the 4547 deaths in this group between 1910 and 1975, only 11 were recorded as resulting from mesothelioma (McDonald et al. 1980). At other sites, especially shipyards, mills, and manufacturing plants, other authors had reported higher incidences among individuals exposed to asbestos (e.g., Elmes et al., 1965 Newhouse and Thompson, 1965). Selikoff reported 15 mesotheliomas out of 199 deaths in 689 asbestos production and textile workers exposed between 1959 to 1971, although only 4 such deaths had been recorded before 1966 (Selikoff et al., 1972). 

C.02.005 states the requirements for the use of automatic, mechanical, and electronic equipment, including computerized systems, and the foreword of the interpretation of regulation C.02.024 the requirements for the maintenance of backup data. The Canadian GMP code does not have correspondence to regulation 211.72, which states the requirements for the filters for liquid filtration used in the manufacture of injectable products. Nor does it cover requirements for the use of fiber-releasing or asbestos-containing filters. 

Differences are found between the maximum values in the Canadian guidelines for sodium (not specified), sulfate (500 mg/L), and total dissolved solids (500 mg/L) and those specified by WHO guidelines for sodium (200 mg/L), sulfate (400 mg/L), and total dissolved solids (1000 mg/L). Asbestos, lead, and arsenic were identified for reconsideration because of high public concern about these substances. The WHO guidelines for lead and arsenic are identical to those found in the current... 

Canadian guidelines, and no limit is set for asbestos in both the WHO standards and the Canadian guidelines. 

The carbon blacks consisted of Spheron 6 and Sterling FT (fine thermal) black, both non-heat-treated and 2700° C. heat-treated (obtained from the Godfrey L. Cabot Co., Boston, Mass.). Published surface areas for the four carbon blacks are 114, 84.1, 15.5, and 12.5 sq. meters per gram, respectively (31). The silica sand was supplied by the New Jersey Silica Sand Co., Millville, N. J., with the manufacturer s designation of No. 325 flour. Screen analysis by the supplier showed a considerable range in particle size about 60% was retained on a 90-mesh screen and 90% on a 200-mesh screen. Finally, a sample of asbestos was tested (obtained from the Canadian Johns-Manville Co., Port Credit, Toronto, with the designation 7R). Zettlemoyer (31) has studied this material. 

An i/8-inch thick compressed asbestos gasket failed on a 20-inch (50.8 cm) Class 6(X) ASM flange after a regular semiannual turnaround. About 66 pounds (30 Kg) of hydrogen leaked from the manway flange on a compressor knockout drum, ignited, and exploded. Two employees died and two other employees were injured in this incident in a Canadian styrene plant. [15]... 

Exports of asbestos were low until the mid-1960s when a significant increase in exports oeeurred. In reeent years, export volumes have generally deereased from 132 million pounds (60,000 metric tons) in 1987 to 48 million pounds (22,000 metric tons) in 1991and 39.6 million pounds (18,000 metric tons) in 1994. In 1999, exports of unmanufactured asbestos were approximately 47.7 million pounds (21,700 metrie tons), of whieh approximately 15.4 million pounds (7,000 metric tons) were of domestic origin. These exports ineluded asbestos erodes, fiber, stucco sand, and refuse. Re-exports of Canadian... 

Begin R, Boileau R, Peloquin S. 1987a. Asbestos exposure, cigarette smoking, and airflow limitation in long-term Canadian chrysotile miners and millers. Am J Ind Med 11 55-66. 

Pooley FD. 1976. An examination of the fibrous mineral content of asbestos lung tissue from the Canadian chrysotile mining industry. Environ Res 12 281-298. 

Robb JA, Hammar SP, Yokoo H. 1993. Pseudomesotheliomatous lung carcinoma a rare asbestos-related malignancy readily separable from epithelial pleural mesothelioma. 1993 Annual Meeting of the United States and Canadian 68(1) 134A. 

Nolan R. P., Langer A. M., Ross M., Wicks F. J., and Martin R. F. (eds.) (2001) The Health Effects of Chrysotile Asbestos Contribution of Science to Risk-Management Decisions. The Canadian Mineralogist Special Publication No. 5, 304pp. 

Aluminum production workers are exposed to PAHs [L], asbestos, fluorides [H], sulfur dioxide [-2.20], and magnetic fields. A case control Canadian study showed increased risks of lung cancer in aluminum production workers. I54l... 

Desired minerals are always mixed with other rocks that must be separated. In many cases, particularly for more valuable metals, the mineral that is sought is less than 1% of the ore. This requires processing of the ore, a procedure called beneficiation, which produces relatively large amounts of finely divided by-product rock. For economic reasons, beneficiation is usually carried out at the mine site with the residues returned to the mine or left in piles at the site. As a result, water pollution problems may develop from the leaching of mine spoils. Some communities in the vicinity of lead mines have been contaminated by lead from mine residues, with particular concern over the health of exposed children. Spoils from iron mining in Minnesota have contaminated water with an asbestos-like mineral associated with the iron ore, requiring remedial action that has cost millions of dollars. Enormous piles of tar-contaminated sand are left over from the extraction by hot water of heavy crude oil from tar sands in the Canadian province of Alberta. 

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