Silicosis and coal worker's pneumoconiosis are serious occupational respiratory diseases associated with the coal mining industry and the inhalation of respirable dusts that contain crystalline silica. Silica exposure is an occupational health priority even when exposure has ceased or is below the occupational exposure limit (0.1 mg/m3). The objective of this study was to determine the individual contributions of the underground coal mining tasks to the total amount of respirable dust and respirable silica dust concentrations found in this environment. The tasks that were identified were continuous miner (CM) cutting, construction, the transfer point, tipping and roof bolting. Respirable dust sampling was conducted at the intake and return of each task, as well as at the intake and return of the section and the intake airway to the section. The five occupations that perform these tasks were also sampled to determine the personal exposure levels. Respirable dust concentrations and small concentrations of respirable silica dust were found in the intake airway and intake of the section, indicating that the air that enters the section is already contaminated. The respirable dust-generating hierarchy of the individual tasks was: transfer point>CM right cutting> CM left cutting> CM face cutting> construction> roof bolting > tipping. For respirable silica dust the hierarchy was: CM left cutting> construction> transfer point> CM right cutting. CM face cutting, tipping and roof bolting generated concentrations of below quantifiable levels. The personal exposures also differed and the eM and stamler operators had the highest exposure to respirable dust (3.417 ± 0.862 mg/m3) and respirable silica dust (0.179 ± 0.388 mg/m3) concentrations, respectively. Recommendations have been included for lowering the respirable dust and silica dust concentrations that are generated and that the workers are exposed to underground. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2010.

Silicosis and coal worker's pneumoconiosis are serious occupational respiratory diseases associated with the coal mining industry and the inhalation of respirable dusts that contain crystalline silica. Silica exposure is an occupational health priority even when exposure has ceased or is below the occupational exposure limit (0.1 mg/m3). The objective of this study was to determine the individual contributions of the underground coal mining tasks to the total amount of respirable dust and respirable silica dust concentrations found in this environment. The tasks that were identified were continuous miner (CM) cutting, construction, the transfer point, tipping and roof bolting. Respirable dust sampling was conducted at the intake and return of each task, as well as at the intake and return of the section and the intake airway to the section. The five occupations that perform these tasks were also sampled to determine the personal exposure levels. Respirable dust concentrations and small concentrations of respirable silica dust were found in the intake airway and intake of the section, indicating that the air that enters the section is already contaminated. The respirable dust-generating hierarchy of the individual tasks was: transfer point>CM right cutting> CM left cutting> CM face cutting> construction> roof bolting > tipping. For respirable silica dust the hierarchy was: CM left cutting> construction> transfer point> CM right cutting. CM face cutting, tipping and roof bolting generated concentrations of below quantifiable levels. The personal exposures also differed and the eM and stamler operators had the highest exposure to respirable dust (3.417 ± 0.862 mg/m3) and respirable silica dust (0.179 ± 0.388 mg/m3) concentrations, respectively. Recommendations have been included for lowering the respirable dust and silica dust concentrations that are generated and that the workers are exposed to underground. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2010.

Thesis (MPH. (Occupational and Environmental Health))-- University of Limpopo, 2012 / Background: The objective of this study was to quantify personal time-weighted average respirable dust and silica exposure of workers at foundries in Gauteng and to rank the occupations in foundries according to the risk of exposure to silica quartz. Methods: A task-based risk assessment of 56 personal samples from two foundries was conducted. Personal exposure data was collected from workers’ breathing zones for the full working shift. All analyses of samples for silica dust were carried out in the CSIR Centre for Mining Innovation’s Laboratory, which has SANAS accreditation (ISO 17025) for both x-ray powder diffraction and particle size analysis methods. Results: The personal time-weighted average mean and median respirable silica dust concentration was 0.184 mg/m³ and 0.167 mg/m³ respectively. The maximum exposure concentration was 0.835 mg/m³ and minimum exposure was 0.010 mg/m³. The occupations within the foundries with the highest exposures were moulders, sand mixers, furnace operators and the lowest exposed occupations were grinders, closers, and casting operators. The majority of foundry workers (62%) in both foundries are exposed to respirable silica dust at above the South African occupational exposure level (OEL). Conclusion and recommendations: Foundry workers are over-exposed to respirable silica dust and are potentially at high risk of contracting silicosis and other occupational diseases associated with respirable silica dust. It is recommended that a dust control programme be implemented and a baseline study be conducted.

Thesis (MPH.) --University of Limpopo, 2006 / Studies conducted on people who reside next to dust producing mines and industries show major health risks. Air pollutants from the mine and industries are inhaled by exposed miners and people who live in the vicinity (Steenland, 1995). Aim The aim of the study is to investigate non-occupational exposure to silica dust at gaMaja village in Polokwane, Limpopo Province. Methodology Study design For this study a cross sectional descriptive study design was used. Study site The study was conducted at gaMaja village near Polokwane in the Limpopo Province Sampling A total sample of 200 villagers participated in the present study. vi Data Collection Two hundred questionnaires were used to collect survey data and were coupled with four dust deposition gauges. The four gauges were mounted at four different positions in the village and were left for six hours. Data Analysis Questionnaires were analysed using SPSS computer software to determine silica-related illnesses and indicators of exposure to silicosis susceptibility. Dust samples from dust deposition gauges were analysed using a Varian 110 atomic absorption spectrometer for determination of silicon. Results The majority of both male and female participants reported that they do not wheeze (81.4%) or bring out phlegm from their chest (71.4%) as compared to those who reported episodes of cough (48%). Gauges were able to identify exposure to a particular pollutant, silica dust, and were successful.Discussion Data from questionnaires revealed that villagers do not show signs and symptoms related to silicosis, however, that does not rule out infection in a long run. The results from dust samples that were collected reveal that there are traces of silica (crystabolite) in the village of gaMaja. Dust samples were collected during normal production at the mine in the middle of summer. Conclusion Findings from this study show that people residing next to dust producing mines and industries are at high risk of health hazard. Mining companies and policy makers should take note of the findings while planning preventive strategies for reduction of air pollutants.

Abstract Background: The high prevalence of smoking on the mines contributes significantly to the public health burden due to exposure to crystalline silica dust and high HIV and TB prevalence rates. Progressive anti-tobacco legislation that informs workplace smoking policies is in existence but there are no formal smoking interventions to achieve the objectives of such policies and to facilitate health promotion. Health care workers, in particular have a vital role to play in this regard. Objectives: The objectives of this research study were to determine the knowledge, attitudes and practices of HCWs regarding prevention of smoking in gold mine workers and to use this information to propose a framework for a smoking intervention programme for the mines. Methods: This was a cross-sectional descriptive knowledge, attitudes and practice (KAP) study. Data were obtained from 69 HCWs using self-administered questionnaires, from 161 occupational lung disease (OLD) and 30 medical ward admission record reviews, and from 4 informal discussions. Results: While knowledge and attitudes about smoking was good overall and 84.1% of HCWs reported that they would routinely ask smoking status and document it, this was not done in practice. An overwhelming majority of HCWs are aware that smoking is harmful to one’s health (98.6%); is harmful to mine workers’ health (97.1%), and predisposes them to acquiring lung diseases (95.7%). Half (56.7%) of the nurses, but no doctors documented smoking history on admission and poor follow up of this advice (38.5%) is an area of concern. HCWs identified a need for support structures such as workplace and community programmes that include education, training and awareness campaigns. Conclusion: Overall, HCWS are responsive to workplace smoking interventions: they are knowledgeable, and show insight and have positive attitudes towards smoking interventions, but a more enabling environment is required to establish good workplace practices. To this end a “Proposed framework for smoking interventions on the mines, incorporating the HCW programme” has been developed and partially implemented. Awareness of this study and its preliminary findings has already demonstrated a paradigm shift in thinking about tobacco on the gold mines.

Le mésothéliome pleural est considéré comme très spécifique d’une exposition à l’amiante. Cependant, certains aspects de l’étiologie de cette maladie n’ont pas encore été bien caractérisés. Les objectifs de cette étude sont : i) d’estimer la relation dose-effet entre exposition professionnelle aux fibres d’amiante et survenue de mésothéliome pleural selon différents indicateurs temporels d’exposition ; ii) d’étudier l’effet d’une exposition professionnelle aux laines minérales et aux poussières alvéolaires de silice cristalline libre sur le risque de survenue de mésothéliome pleural et iii) d’identifier les professions et secteurs d’activité à risque de survenue de mésothéliome pleural à partir de données recueillies sur une période de 20 ans. Les cas provenaient de ceux recrutés dans une précédente étude cas-témoins réalisée entre 1987 et 1993 et des cas enregistrés dans le programme national de surveillance du mésothéliome entre 1998 et 2006 (1 199 hommes). Les témoins ont été appariés en fréquence sur l’année de naissance et le sexe (2 378 hommes). L’exposition professionnelle à l’amiante, aux laines minérales et à la silice a été évaluée à partir de matrices emplois-exposition. Les relations dose-effet ont été estimées à l’aide du modèle logistique et leur forme a été obtenue grâce à l’utilisation de fonctions splines cubiques restreintes. Si la relation dose-effet à l’amiante est bien confirmée (particulièrement aux faibles doses), cette étude apporte de nouveaux résultats sur la relation temps-effet (rôle du temps écoulé depuis la dernière exposition ou effet de l’âge à la première exposition). Elle ouvre également de nouvelles perspectives sur le rôle des co-expositions (laines minérales) et permet d’identifier de nouvelles activités à risque, comme les mécaniciens automobiles. / Asbestos exposure is recognized as the primary cause of pleural mesothelioma. However, some aspects of etiology of this disease have not been well characterized. The objective of this study was to elucidate dose-response relationships of temporal pattern of occupational asbestos exposure in males, using case-control data, to study effect of man made vitreous fibers and silica dust on the risk of pleural mesothelioma and finally, to describe occupations and industries at high risk for this cancer among men in France according a period of twenty years of observation. Cases came from a French case-control study conducted in 1987-1993 and from the French National Mesothelioma Surveillance Program in 1998-2006 (1,199 males). Population controls were frequency matched by sex and year of birth (2,378 males). Occupational asbestos exposure was evaluated with a job-exposure matrix. The dose-response relationships were estimated using logistic regression models and form of this relationship were estimated using restricted cubic spline functions. Dose-response relationship was confirmed (particularly for lowest doses). However, this study provides new results about time-effect relationships (role of time since last exposure or effect of age at first exposure). This study opens up new prospects on the role of co-exposure (mineral wool) and permit to identify new activities at risk for pleural mésothéliome as motor vehicle mechanics.

Kvartsdamm är ett arbetsmiljöproblem som kan leda till allvarliga konsekvenser för de exponerade yrkesarbetarna. De sjukdomar som ligger till följd för en hög exponering av kvartsdamm är framförallt silikos, KOL och lungcancer. Kvartsdammet uppstår då byggmaterial som innehåller kvartshaltigt material bearbetas, tillexempel betong. De små respirabla partiklarna av kvarts som uppstår vid bearbetningen bildar ärrvävnader i lungorna, vilket leder till att dem tappar sin kapacitet. Tidigare har krav ställts att arbetsplatserna ska utföra egna mätningar av kvarts, men inte längre. Nya författningssamlingen, AFS 2015:2 gör det möjligt för byggarbetsplatserna att använda sig av referensvärden och kringgå faktiska mätningar vid riskbedömningen av kvartsdamm. Examensarbetet redovisar några utav de hjälpmedel som används för en minskad exponering av dammet, där syftet är att hitta de största bristerna hos fallföretaget i byggproduktionen samt se hur den övergripande kunskapen ser ut på byggarbetsplatserna.Informationen till arbetet har samlats in från olika informationskällor, bland annat kvantitativa enkätundersökningar, semistrukturerade intervjuer samt informationssökning via internet där primärkällor prioriterats. Alternativa fakta har sorterats ut för en minskad avgränsning då examensarbetet enbart inriktar sig på den praktiska hanteringen av kvartsdamm.Examensarbetets resultat förväntas göra företagets riskbedömningsmall för kvartsdamm mer hanterbar genom den förenkling som tagits fram under arbetets gång. Diskussionerna har i huvudsak kretsat kring självkritisk bedömning av informationsinsamlingen samt hur utfallet av rapporten hade ändrats om fokus lades på andra delar vid arbetets början.Fallföretaget arbetar konstant med riskbedömning av kvarts för att uppnå en fullgod arbetsmiljö. En rotorsak var svårigheter kring just hanteringen av referensvärdena som gör att företaget inte använder riskbedömningsmallen som ett hjälpmedel. Då kvartsdamm ska bedömas i arbetsberedningarna är tanken att riskbedömningen som utförts i ett tidigare skede ska underlätta arbetet. Även kunskapen om kvartsdamm var varierande, där de anställda hos de större företagen har goda kunskaper medan de mindre underentreprenörerna har bristfälliga kunskaper. / Quartz dust is a health and safety problem that has serious consequences for the exposed workers. The diseases that are due to excessive exposure of silica are silicosis, COPD and lung cancer. The quartz dust occurs when building materials that containing quartz are processed, such as concrete. The small respirable quartz dust particles that occur during processing form scar tissues in the lungs, causing them to lose their capacity. In the past, demands have been made that workplaces should carry out their own measurements of quartz, but no longer. The new regulation, AFS 2015:2, enable construction sites to use benchmarks and circumvent actual measurements in the risk assessment of quartz dust. The study reports some of the tools used to reduce exposure to the dust, where the purpose is to find the biggest shortcomings of the case company in the construction production and see how the overall knowledge looks at the construction sites.The information for the work has been collected from various sources of information, including quantitative surveys, semi structured interviews and information retrieval via the Internet where primary sources have been prioritized. Alternative facts have been sorted out for a reduced demarcation as the degree project focuses solely on the practical handling of quartz dust. The discussion mainly revolved around self-critical assessment of information gathering. The discussion has also investigates how the outcome of the report have been changed if the focus had been other parts at the start of work.The case the company is constantly working with risk assessment of quartz to achieve an acceptable working environment. A isolating was a problem in dealing with the reference values, which means that the company does not use the risk assessment template as an aid. When quartz dust is to be assessed in the working preparations, the idea is that the risk assessment template facilitates the work. The knowledge of quartz dust was also variable, where the employees of the larger companies had good knowledge while the smaller subcontractors had inadequate knowledge.