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Exposition professionnelle aux poussières respirables et au quartz respirable dans les mines métalliques du Nord-Ouest québecois

The goal of this study was to verify if differences in respirable dust and respirable quartz concentrations exist with respect to the mines, the ore deposit types and the nature of workstations. / One hundred and seventy-nine respirable dust samples were collected in the six mines studied, in compliance with the method recommended by the Institut de recherche en sante et securite du travail du Quebec (IRSST). Then, samples were analysed using X ray powder diffraction technique to determine respirable quartz concentrations. / Results indicated statistically significant differences in the normalised exposure levels to respirable dust (p = 0.017), to respirable quartz (p < 0.001) as well as the quartz percentage in the respirable dust (p < 0.001) of the six mines studied. When grouped by ore deposit type, normalized exposure levels to respirable dust were not statistically different. However, statistically significant differences were noticed for normalized exposure levels to respirable quartz (p = 0.004) and respirable quartz percentage (p < 0.001) according to ore deposit types. / For all mines studied, respirable dust concentrations were all below the admissible exposure value whereas about 9% of the respirable quartz concentrations were equal or above the admissible exposure limit. Gold ore deposits hosted in quartz veins had the highest normalized respirable quartz exposure levels, as well as the highest percentage of quartz in the respirable dust when compared to gold ore deposits with sulfide lodes, the copper-zinc ore deposit and the disseminated gold ore deposit. / The study also revealed that workers who worked in the ore crushing and hoisting departments as well as loading and transport had higher normalised exposure levels to respirable quartz than workers who worked in the drilling and blasting or those who worked in the maintenance department. / In conclusion, this study stressed that quartz content in the mined rocks seems to be the most important factor influencing on respirable quartz concentrations in the mine worker's respiratory zone, but the relation between the two variables were not strongly correlated (Rs = 0.254, p = 0.005). Furthermore, the study showed that the gold ore deposits with quartz lodes had the highest normalized exposure levels to respirable quartz. Also, the workers assigned to ore crushing and hoisting departments as well as transport and loading had the highest exposure levels to respirable quartz. (Abstract shortened by UMI.)

Identiferoai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.36932
Date January 2000
CreatorsGagné, Lise.
ContributorsDufresne, Andre (advisor), Perrault, Guy (advisor)
PublisherMcGill University
Source SetsLibrary and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada
LanguageFrench
Detected LanguageEnglish
TypeElectronic Thesis or Dissertation
Formatapplication/pdf
CoverageDoctor of Philosophy (Department of Occupational Health.)
RightsAll items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated.
Relationalephsysno: 001804229, proquestno: NQ70024, Theses scanned by UMI/ProQuest.

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