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Article

Trends in Exposure to Diesel Particulate Matter and Prevalence of Respiratory Symptoms in Western Australian Miners

by
Krassi Rumchev
1,*,
Dong Van Hoang
2 and
Andy Lee
1
1
School of Public Health, Curtin University, Perth 6120, Australia
2
Department of Epidemiology and Prevention, Center for Clinical Sciences, National Center for Global Health and Medicine, Tokyo 162-8655, Japan
*
Author to whom correspondence should be addressed.
Int. J. Environ. Res. Public Health 2020, 17(22), 8435; https://doi.org/10.3390/ijerph17228435
Submission received: 19 October 2020 / Revised: 6 November 2020 / Accepted: 10 November 2020 / Published: 14 November 2020
(This article belongs to the Special Issue Indoor Air Quality at Home, School, and Work – Challenges and Considerations)
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Abstract

:
Diesel-powered equipment is used frequently in the mining industry. They are energetically more efficient and emit lower quantities of carbon monoxide and carbon dioxide than the gasoline equipment. However, diesel engines release more diesel particulate matter (DPM) during the combustion process which has been linked to harmful health effects. This study assessed the trends in DPM exposure and the prevalence of respiratory symptoms among Western Australian miners, using the available secondary data collected from 2006 to 2012. The data consisted of elemental carbon (EC) concentrations and information on miner’s respiratory symptoms. The measured EC concentrations from n = 2598 miners ranged between 0.01 mg/m3 and 1.00 mg/m3 and tended to significantly decrease over the study period (p < 0.001). Underground mine workers were exposed to significantly higher (p < 0.01) median EC concentrations of 0.069 mg/m3 (IQR 0.076) when compared to surface workers’ 0.038 mg/m3 (IQR 0.04). Overall, 29% of the miners reported at least one respiratory symptom, with the highest frequency recorded for cough (16%). Although the exposure levels of DPM in the mining industry of Western Australia have declined over the study period, they are still high and adhering to stringent occupational standard for DPM is recommended.

1. Introduction

Diesel-powered vehicles provide the main source for transport in the mining industry. They are more efficient, energetically more effective, and emit less carbon monoxide and carbon dioxide than their gasoline counterpart [1]. Despite all the advantages, diesel-powered engines emit more diesel particulate matter (DPM) than gasoline equipment during the combustion process [2,3,4]. DPM is composed of elemental carbon (EC) onto which organic carbon (OC) compounds and other particles (unburnt fuel, lubricant droplets, metallic additives, etc.) are adsorbed. The sum of OC and EC in the DPM fraction represents the total carbon (TC). TC is frequently used as an indicator of DPM exposure, but OC from other sources, such as cigarette smoke, oil mist, and other fuels, may interfere with the analysis [5,6]. Therefore, measurements of EC have been proposed to reduce the influence of OC contamination in DPM assessments [5,7,8].
Approximately 80–95% of the diesel particle mass is in the fine particle size range (≤2.5 μm), with a mean particle aerodynamic diameter of about 0.2 μm [8]. Particles with aerodynamic diameters >2.5 μm (i.e., >PM2.5) tend to be retained in the upper portions of the respiratory tract, whereas particles with diameters <2.5 μm (i.e., PM2.5) are deposited in all areas, especially into the lower part of the respiratory tract, including the alveolar region [8,9,10,11]. These fine and ultrafine particles have a very large surface area per gram mass, which enables them to adsorb and ultimately transport inorganic and organic compounds into the lung [8,9,12,13].
Short-term health effects from exposure to DPM include throat and bronchial irritation, cough, phlegm, and neurophysiological symptoms [8,14]. Combined experimental and human chronic exposure studies show evidence of long-term adverse DPM impact on the respiratory and cardiovascular systems [8,15,16,17,18,19]. Based on the proven genotoxicity of its constituents, diesel exhaust has been confirmed as mutagenic and carcinogenic to humans by the World Health Organization in 2010 [20]. In June 2012, the International Agency for Research on Cancer (IARC) classified diesel engine exhaust as a Group 1 carcinogen to humans.
Mine workers are exposed to far higher DPM concentrations than other professionals. Coble and colleagues [21] found the average EC level measured for underground miners ranged from 64 to 195 µg/m3, which is approximately twice the level measured for surface workers (38 to 71 µg/m3). The EC exposure levels for truck, bus, and taxi drivers were generally between 1–10 µg/m3, but for fire fighters they were mostly non-detectable [22]. In Australia, the EC levels among miners ranged between 10 and 420 µg/m3 for coal mines and between 11 and 117 µg/m3 for underground metal mines [23,24] (AIOH, 2013; Irving G, 2006).
The occupational exposure limit (OEL) for diesel emission varies between and within countries. In the province of Quebec, Canada, the limit of 400 µg/m3 (0.40 mg/m3) for TC was established in 2016 [25]. The U.S. Mine Safety and Health Administration has recommended an 8-h OEL of 160 µg/m3 (0.16 mg/m3) for TC [7]. However, there is no current occupational exposure standard for DPM in Australia. The Australian Institute of Occupational Hygiene [23] has set a guideline value whereby workers exposed to DPM should be controlled to below 100 µg/m3 (0.1 mg/m3) as an 8 h time weighted average value, measured as submicron EC, which is approximately equal to 0.16 mg/m3 TC or 0.2 mg/m3 diesel particulate.
The present study investigated the trends in DPM concentrations and prevalence of respiratory symptoms among workers in Western Australian mines for the period 2006–2012. The findings can contribute for setting a standard concerning DPM exposure level in the Australian mining industry.

2. Materials and Methods

2.1. DPM Exposure Measurement

All mining companies in Western Australia were required by the government to conduct regular exposure assessments of selected contaminants among mine workers. The mining sector produces more than 50 different minerals from about 1000 operating mines in Western Australia. Most diesel engines in underground mines are used to power support equipment and not production equipment, mainly for loading and hauling operations. They can be classified under three categories: permissible diesel equipment, heavy-duty non-permissible, and light-duty non-permissible diesel equipment. Additionally, there are four types of diesel engines, with Tier 3 and 4 engines having the lowest diesel emissions, although Tier 1 and 2 engines are still used in Australia [26], as they comply with the government standard, AS/NZS 3584 Set: 2012 Diesel Engine Systems Standards for Underground Coal Mines.
The sampling quota was determined for each mining site to ensure a representative sample. Personal exposure monitoring was conducted four times a year at each mine site. All data were submitted electronically within six weeks and systematically recorded in the CONTAM database, which is operated and managed by the Department of Mines and Petroleum (DMP), Western Australia (WA).
EC, as a marker for DPM exposure, was measured for the mining employees from 2006 until the end of 2012 following the NIOSH Method 5040 [27]. DPM Plastic Cyclone 37 mm has been used to meet the NIOSH 5040 specifications. The SKC DPM Cassette has a built-in impactor, which performs the differentiation of DPM, where respirable dust with particle size ≥1.0 μm is screened out, leaving only those with particle size <1.0 μm collected on the filter. The sampler was attached to a personal sampling pump and clipped onto clothing in the breathing zone of mine workers. The sampling flow rate was maintained at between 2 to 4 L/min. The work shift length of monitored miners was either 8 h or 12 h.

2.2. Respiratory Health Surveillance

In addition to the contaminant exposure assessment, the Mines Safety and Inspection Act 1994 and Regulations 1995 required a regular respiratory health surveillance to identify those with elevated dust exposures and risk for the development of respiratory symptoms. The health surveillance questionnaire was administered after a worker had entered the Western Australian mining industry, and then periodically or as directed. The respiratory health data were stored in the MineHealth database.
Questionnaires and consent forms were administered to randomly selected mine workers by the mining companies following guidelines from the DMP. The standardized questionnaire consisted of questions including gender, age, job title, shift length and pattern, use of respirator mask during work, and current smoking status (smoker, non-smoker). Mine workers were asked to report current respiratory symptoms and occurring in the last 3 months, namely, ‘cough’ (usually cough first in the morning, during the day or at night), ‘phlegm’ (usually bring up phlegm first in the morning, during the day or at night), ‘wheeze’ (ever experience of the chest sounding wheezy or whistling), ‘breathlessness’ (either short of breath at rest or on activity), and ‘any respiratory symptom’ (having at least one of the above symptoms). Responses to the respiratory questions were binary (yes/no). Mine companies were responsible for the data collection process and entry of the hygiene and health data directly into the Safety Regulations System (SRS). The CONTAM and MineHealth database were then linked and records were matched by the DMP, WA, using each worker’s unique identifier number.

2.3. Occupational Grouping

There were 87 place descriptions and 129 jobs in the original dataset. To facilitate analysis, the occupation groups were classified as either ‘surface production and services’ or ‘underground mining.’ The first group consisted of occupations in which workers were not exposed or had limited exposure to heavy diesel equipment. They included a wide range of professional activities related to geologists, mobile plant operators, engineers, electricians, and mechanics. The second group comprised mine workers who were involved in mining production or development, drilling, blasting, loading, and transport operations.

2.4. Statistical Analysis

Characteristics of the analytic sample were described by means (SD) for continuous variables, and percentages for categorical variables. The annual median (IQR) EC concentrations were calculated and stratified by occupation (surface production and services; underground mining), mask wearing status (yes; no), and work shift length (8 h; 12 h). Prevalence of each and any respiratory symptom was calculated annually. The overall prevalence (across all years) of respiratory symptoms was then compared with respect to occupation, mask wearing, work shift length, and current smoking status (smoker; non-smoker). Logistic regression was then conducted to estimate the risk of respiratory symptom for any apparent association from the univariate analysis, with “respiratory symptom status” (0 = no; 1 = yes) as the dependent variable. The linear time trend in EC levels was tested by assigning ordinal numbers (1–7) to each year (2006–2012), then fitting a linear regression model of the EC concentration for the entire dataset (n = 2598). The linear time trend in the prevalence of any respiratory symptom was assessed in a similar manner. All statistical analyses were performed in RStudio for Windows version 3.2.4 (RStudio Team 2012, Boston, MA, USA).

3. Results

3.1. Study Population

The CONTAM database contained 6785 DPM records for the period 2006–2012, with a total of 124 mines being assessed for exposure to EC. After excluding (i) workers who had been surveyed in previous year(s), (ii) observations with work shift length <8 or >12 h, and (iii) those workers whose occupation was not related to mining activity, the final analytic sample comprised n = 2598 workers from the total N = 2964 eligible miners participating in the surveys (Table 1). Among them, 2471 (95%) were male workers. The mean age of the study population was 35 ± 10 years, and 93.5% were occupied in underground mining activities. The great majority of mine workers did not wear protective equipment from dust exposure (90.1%) and worked long, 12-h shifts (90.6%). Just over one-third of them were current smokers (36.7%).

3.2. EC Exposure

Table 2 presents the average EC concentration by occupation, respiratory mask wearing status, and shift length. The EC exposure levels ranged between 0.01 mg/m3 and 1.00 mg/m3 and steadily declined over the study period (p for decreasing time trend <0.001); and the median concentrations were below the Australian guideline of 0.1 mg/m3 (Figure 1). The underground miners were exposed to significantly higher (median 0.069 mg/m3) levels of EC than those involved in surface operations (median 0.038 mg/m3). Stratified by respiratory protective equipment, mine workers who did not wear a respiratory mask during work were exposed to significantly higher EC concentration (median 0.07 mg/m3), when compared with those who used such protection equipment (median 0.04 mg/m3). However, it appears that the length of work shift did not have an effect on the EC exposure levels of miners.

3.3. Respiratory Health

Table 3 summarizes the prevalence of respiratory symptoms for mine workers over the study period. Overall, 28.6% of the miners reported at least one respiratory symptom, with the highest frequency recorded for cough (15.7%).
As shown in Figure 1, the declining time trend in the prevalence of any respiratory symptom is evident (p = 0.029) and in line with the reduced EC concentrations over the study period.
When stratified by occupation, shift length, respiratory mask wearing status, and smoking status (Table 4), higher frequencies of respiratory symptoms were observed for workers involved in underground mining and among those who had no protection from dust exposure, particularly for cough (p = 0.017 and p = 0.036, respectively). The prevalence of respiratory symptoms was similar between miners who worked 12 h and 8 h shifts. As expected, smokers reported significantly higher prevalence of all respiratory symptoms than their non-smoking counterparts (p < 0.001).
According to logistic regression analysis, the risk of cough was significantly higher (p = 0.025) among underground miners than surface workers after adjustment for their age and smoking status, the estimated odds ratio being 1.64 (95% confidence interval 1.08–2.58).
Table 5 shows that mine workers who reported cough and phlegm were exposed to elevated EC concentrations (p < 0.001), when compared to those without such symptoms. In addition, the respiratory symptoms appeared to be more common among older mine workers (Table 5).

4. Discussion

This study assessed exposure to EC levels among a large population of mine workers in Western Australia and their respiratory health for the period 2006–2012. A key finding was that underground miners were exposed to significantly higher EC concentrations than surface production workers over the study period, except in 2006, probably due to limited DPM monitoring of underground miners before the introduction of the exposure guideline by the Australian Institute of Occupational Hygiene in 2007 [28].
The findings indicated that 90% of workers did not wear protective equipment when working in dusty environments, which contributed to their elevated EC levels. Although the EC concentrations ranged from 0.01 to 1.00 mg/m3 in this study, the estimated median exposures tended to decline over the study period and were below the Australian guideline value of 0.1 mg/m3.
A study of metalliferous underground mining operations in Queensland [24] showed similar EC levels of 0.01 to 0.117 mg/m3 for underground operators. A comparison with international studies indicated that levels in WA mines were of similar or less order of magnitude as found in the mining industry elsewhere in the world. In the USA, the average EC levels measured for underground miners ranged from 0.064 to 0.19 mg/m3, while lower EC levels for the surface workers were measured, with a range between 0.04 to 0.07 mg/m3 [21]. Similar recordings were reported in a study from Canada with the mean exposure ranging from 0.04 to 0.160 mg/m3 [29]. In a more recent study conducted among underground miners in Sweden, EC exposure levels varied from 0.05 to 0.061 mg/m3 [30]. Exposure levels of EC among underground miners were measured in a US goldmine (1990s), where the diesel equipment had no emission control devices, and they ranged from 0.305 to 1.165 mg/m3 [31].
These wide range in EC exposure levels may be due to high variability between facilities and suggests that other determinants, such as type of diesel equipment, maintenance, and ventilation efficiencies in different mine sites, may also play a role in the exposure levels to diesel particulates. Sampling procedures could also differ between mine sites.
The median EC concentrations observed in our study are at the lower end of the exposure levels reported in most international studies. The rapid decline in EC exposure level in 2007 can be explained by the introduction of DPM guideline value in the same year [28]. Since then, mining companies have embarked on utilizing control technologies to reduce diesel emissions in underground mines. The implemented efforts for controlling diesel exhaust in the Australian mines included vehicle standards and statutory implications [32], vehicle management strategies [33], alternative diesel fuels [34], ultrasonic transducers with electrostatic perspiration filter [35], and cooled exhaust and scrubber [36].
Mining activities, both surface and underground, have been associated with adverse health conditions, including acute and chronic respiratory diseases. In this study, 29% of the interviewed miners reported at least one respiratory symptom over the six-year study period, with the highest frequency recorded for cough (15.7%), followed by phlegm (11.7%), wheeze (10.5%), and breathlessness (9.6%). Somewhat higher rates of prevalence for cough (28.3%) and breathlessness (22.3%) were found among miners in one study [37], but much lower prevalence rates had been reported in another study [38], namely, 9% and 3%, respectively. The observed decreasing trend in respiratory symptoms could be associated with the apparent reduction in EC concentration over the years, but might also be attributed to the improved illnesses prevention and management in the Australian healthcare system [39]. Meanwhile, there has been a continuing decline in the daily smoking rate among the general population, from 22.4% in 2001 to 18.9% in 2007 and 16.3% in 2011 [40]. Smoking is well recognized as an independent predictor of declines in respiratory health and significantly higher prevalence of cough and phlegm was evident among current smokers in this study. Similar findings have been established in other studies, although at lower rates [41,42]. Overall, 42% of miners who smoked reported a respiratory symptom, as compared to 21% of those who did not smoke.
Underground miners appeared to be more susceptible to respiratory illness, in line with their elevated EC exposure levels, while those who reported cough and phlegm were exposed to significantly higher EC concentrations than others without such symptoms. The present study found that the prevalence of cough among underground miners was 64% higher than that of surface workers, consistent with the findings of a previous study [43]. Moreover, our reported overall prevalence of cough (15.7%) for the miners was higher than that of the general population (12.5%) [44].
The EC concentrations found in this study are within the recommended guideline value of 0.1 mg/m3. However, a study by Vermeulen and colleagues [45] showed an increased risk of lung cancer at these levels. They estimated excess lung cancer deaths per 10,000 individuals for average lifetime occupational exposure levels between 0.001 and 0.025 mg/m3 (1–25 μg/m3); similar values have been recorded in our study.
The use of administrative databases was a strength of the present study, which provided access to a large data set. Similar studies have been conducted in China [46,47], in another large international study that involved a number of European countries [48], and in a joint study of Europe and Canada [49]. The outcomes of these studies clearly demonstrate the feasibility of this approach in occupational exposure assessment, although the authors of the current study acknowledge the use of existing data without involvement in the data collection process as a study limitation. The reliance on self-reported respiratory symptoms without medical diagnoses posed another limitation for this study. Nevertheless, self-report data from the respiratory health survey were used in conjunction with the quantitative DPM measurements and other information through record matching and data linkage to reduce bias and inaccuracy [50].

5. Conclusions

The concentrations of DPM in the mining industry of WA was still high, despite the reductions in exposure levels in recent years and the apparent declining trend in the prevalence of respiratory symptoms. The findings suggest that stringent occupational standard for DPM should be maintained in order to protect the respiratory health of mine workers.

Author Contributions

Conceptualization, K.R. and A.L.; methodology, K.R. and A.L.; formal analysis, D.V.H.; investigation, K.R.; writing—original draft preparation, K.R.; writing—review and editing, K.R., A.L. and D.V.H. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Acknowledgments

The authors acknowledge the Department of Mines and Petroleum, WA, for providing the data.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Sullivan, J.L.; Baker, R.E.; Boyer, B.A.; Hammerle, R.H.; Kenney, T.E.; Muniz, L.; Wallington, T.J. CO2 Emission Benefit of Diesel (versus Gasoline) Powered Vehicles. Environ. Sci. Technol. 2004, 38, 3217–3223. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  2. Hesterberg, T.W.; Long, C.M.; Sax, S.N.; Lapin, C.A.; McClellan, R.O.; Bunn, W.B.; Valberg, P.A. Particulate matter in new technology diesel exhaust (NTDE) is quantitatively and qualitatively very different from that found in traditional diesel exhaust (TDE). J. Air Waste Manag. Assoc. 2011, 61, 894–913. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  3. Chan, T.L.; Ning, Z.; Wang, J.S.; Cheung, C.; Leung, C.; Hung, W.-T. Gaseous and Particle Emission Factors from the Selected On-Road Petrol/Gasoline, Diesel, and Liquefied Petroleum Gas Vehicles. Energy Fuels 2007, 21, 2710–2718. [Google Scholar] [CrossRef]
  4. Jayaram, V.; Agrawal, H.; Welch, W.A.; Miller, J.W.; Cocker, D.R. Real-Time Gaseous, PM and Ultrafine Particle Emissions from a Modern Marine Engine Operating on Biodiesel. Environ. Sci. Technol. 2011, 45, 2286–2292. [Google Scholar] [CrossRef] [Green Version]
  5. Birch, M.E.; Cary, R.A. Elemental carbon-based method for occupational monitoring of particulate diesel exhaust: Methodology and exposure issues. Analyst 1996, 121, 1183–1190. [Google Scholar] [CrossRef]
  6. Bakke, B.; Ulvestad, B.; Thomassen, Y.; Woldbæk, T.; Ellingsen, D.G. Characterization of Occupational Exposure to Air Contaminants in Modern Tunnelling Operations. Ann. Occup. Hyg. 2014, 58, 818–829. [Google Scholar]
  7. US Office of the Federal Register. Limit on Exposure to Diesel Particulate Matter, Code of Federal Regulations Title 30, Part 57.5060(b)(3); US Office of the Federal Register: Washington, DC, USA, 2008; pp. 370–371.
  8. Ris, C. US EPA Health Assessment for Diesel Engine Exhaust: A Review. Inhal. Toxicol. 2007, 19, 229–239. [Google Scholar] [CrossRef]
  9. Sydbom, A.; Blomberg, A.; Parnia, S.; Stenfors, N.; Sandström, T.; Dahlén, S.-E. Health effects of diesel exhaust emissions. Eur. Respir. J. 2001, 17, 733–746. [Google Scholar] [CrossRef]
  10. Riedl, M.; Diaz-Sanchez, D.; Linn, W.; Gong, H., Jr.; Clark, K.; Effros, R.; Miller, W.; Cocker, D.; Berhane, K. HEI Health Review Committee. Allergic Inflammation in the Human Lower Respiratory Tract Affected by Exposure to Diesel Exhaust. Res. Rep. Health Eff. Inst. 2012, 165, 5–43, discussion 45–64. [Google Scholar]
  11. Ristovski, Z.; Miljevic, B.; Surawski, N.C.; Morawska, L.; Fong, K.M.; Goh, F.; Yang, I.A. Respiratory health effects of diesel particulate matter. Respirology 2012, 17, 201–212. [Google Scholar] [CrossRef] [Green Version]
  12. HEI. Research directions to improve estimates of human exposure and risk from diesel exhaust. In A Special Report of the Institute’s Diesel Epidemiology Working Group; Health Effects Institute: Boston, MA, USA, 2002. [Google Scholar]
  13. US EPA. Health Assessment Document for Diesel Engine Exhaust; National Center for Environmental Assessment, Washington Office: Washington, DC, USA, 2002; EPA/600/8-90/057F.
  14. Lloyd, A.C.; Cackette, T.A. Diesel Engines: Environmental Impact and Control. J. Air Waste Manag. Assoc. 2001, 51, 809–847. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  15. Zanobetti, A.; Schwartz, J.; Samoli, E.; Gryparis, A.; Touloumi, G.; Peacock, J.; Anderson, R.H.; Le Tertre, A.; Bobros, J.; Celko, M.; et al. The temporal pattern of respiratory and heart disease mortality in response to air pollution. Environ. Health Perspect. 2003, 111, 1188–1193. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  16. Kaiser, R.; Romieu, I.; Medina, S.; Schwartz, J.D.; Krzyzanowski, M.; Künzli, N. Air pollution attributable postneonatal infant mortality in U.S. metropolitan areas: A risk assessment study. Environ. Health 2004, 3, 4. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  17. Benbrahim-Tallaa, L.; Baan, R.A.; Grosse, Y.; Lauby-Secretan, B.; El Ghissassi, F.; Bouvard, V.; Guha, N.; Loomis, D.; Straif, K. Carcinogenicity of diesel-engine and gasoline-engine exhausts and some nitroarenes. Lancet Oncol. 2012, 13, 663–664. [Google Scholar] [CrossRef] [Green Version]
  18. Pope, C.A., III; Dockery, D.W. Health effects of fine particulate air pollution: Lines that connect. J. Air Waste Manag. Assoc. 2006, 56, 709–742. [Google Scholar] [CrossRef]
  19. Robinson, A.L.; Grieshop, A.P.; Donahue, N.M.; Hunt, S.W. Updating the Conceptual Model for Fine Particle Mass Emissions from Combustion Systems Allen L. Robinson. J. Air Waste Manag. Assoc. 2010, 60, 1204–1222. [Google Scholar] [CrossRef]
  20. WHO. Environmental Health Criteria 229, Selected Nitro- and Nitro-Oxy-Polycyclic Aromatic Hydrocarbons; WHO: Geneva, Switzerland, 2010. [Google Scholar]
  21. Coble, J.B.; Stewart, P.A.; Vermeulen, R.; Yereb, D.; Stanevich, R.; Blair, A.; Silverman, D.T.; Attfield, M. The Diesel Exhaust in Miners Study: II. Exposure Monitoring Surveys and Development of Exposure Groups. Ann. Occup. Hyg. 2010, 54, 747–761. [Google Scholar]
  22. Pronk, A.; Coble, J.; A Stewart, P. Occupational exposure to diesel engine exhaust: A literature review. J. Expo. Sci. Environ. Epidemiol. 2009, 19, 443–457. [Google Scholar] [CrossRef]
  23. AIOH. Position Paper—Diesel Particulate Matter and Occupational Health Issues; Australian Institute of Occupational Hygienists Exposure Standards Committee: Tullamarine, VIC, Australia, 2013. [Google Scholar]
  24. Irving, G. Diesel Particulate Matter in Queensland’s Underground Metal Mines. 2006. Available online: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.613.7646&rep=rep1&type=pdf (accessed on 13 November 2020).
  25. Carex Canada: Diesel Engine Exhaust. Available online: https://www.carexcanada.ca/profile/diesel_engine_exhaust/ (accessed on 13 August 2020).
  26. Department of Mines and Petroleum (DMP). Management of Diesel Emissions in Western Australian Mining Operations. 2013. Available online: http://dmp.wa.gov.au/Documents/Safety/MSH_G_DieselEmissions.pdf (accessed on 13 November 2020).
  27. NIOSH. Diesel Particulate Matter-Manual of Analytical Methods (NMAM). 2003. Available online: https://www.cdc.gov/niosh/docs/2003-154/pdfs/5040.pdf (accessed on 13 August 2020).
  28. Hedges, K.; Djukic, F.; Irving, G.; Fisher, T. Diesel particulate matter in underground mines—Controlling the risk. In Proceedings of the AusIMM New Leaders’ Conference, Brisbane, Australia, 2–3 May 2007; The Australasian Institute of Mining and Metallurgy: Melbourne, Australia, 2007; pp. 53–60. [Google Scholar]
  29. Health Canada. Human Health Risk Assessment for Diesel Exhaust. Cat.: H129-60/2016E-PDF ISBN 978-0-660-04555-9. 2016. Available online: http://publications.gc.ca/collections/collection_2016/sc-hc/H129-60-2016-eng.pdf (accessed on 13 August 2020).
  30. Adelroth, E.; Hedlund, U.; Blomberg, A.; Helleday, R.; Ledin, M.C.; Levin, J.O.; Pourazar, J.; Sandström, T.; Järvholm, B. Airway inflammation in iron ore miners exposed to dust and diesel exhaust. Eur. Respir. J. 2006, 27, 714–719. [Google Scholar] [CrossRef] [Green Version]
  31. McDonald, J.D.; Zielinska, B.; Sagebiel, J.C.; McDaniel, M.R. Characterization of fine particle material in ambient air and personal samples from an underground mine. Aerosol Sci. Technol. 2002, 36, 1033–1044. [Google Scholar] [CrossRef] [Green Version]
  32. O’Beirne, T.; Walton, P.; Morrell, A.; Bell, M.; O’Malley, A. Underground Design Standards and Implications, Reports Report C3063; University of Wollongong: Wollongong, NSW, Australia, 1996. [Google Scholar]
  33. Greenwood, J.; O’beirne, O.; Howard, D. Diesel Management, ACARP, C14028; University of Wollongong: Wollongong, NSW, Australia, 2009. [Google Scholar]
  34. Greenwood, J.; O’beirne, T.; Howard, D.; Ristovski, Z.; Surawski, N.; Miljevic, B. Trailling Alternative Diesel Fuels Reducing DPM & Solving Toxicity,“Toxicity”, ACARP, C18014; University of Wollongong: Wollongong, NSW, Australia, 2011. [Google Scholar]
  35. Glynn, P.; Bates, D.; Clarke, M. Diesel Agglomeration and Removal Ultrasonic Unltrasonic Transducers with Electrostatic Filter,“Filter”, ACARP, C15021; University of Wollongong: Wollongong, NSW, Australia, 2009. [Google Scholar]
  36. Greenwood, J.; Wang, H.; Ristovski, Z.; O’Beirne, T. Effect of Cooled Exhaust and Scrubber on Toxic Particulate Formation, ACARP, C20036; University of Wollongong: Wollongong, NSW, Australia, 2013. [Google Scholar]
  37. Seixas, N.; Robins, T.G.; Attfield, M.D.; Moulton, L.H. Exposure-response relationships for coal mine dust and obstructive lung disease following enactment of the federal coal mine health and safety act of 1969. Am. J. Ind. Med. 1992, 21, 715–734. [Google Scholar] [CrossRef] [PubMed]
  38. Naidoo, R.N.; Robins, T.G.; Seixas, N.; Lalloo, U.G.; Becklake, M. Respirable Coal Dust Exposure and Respiratory Symptoms in South-African Coal Miners: A Comparison of Current and Ex-Miners. J. Occup. Environ. Med. 2006, 48, 581–590. [Google Scholar] [CrossRef] [PubMed]
  39. Australian Institute of Health Care and Welfare (AIHCW). Chronic Respiratory Diseases in Australia. Their Prevalence, Consequences and Prevention Canberra. 2005. Available online: https://www.aihw.gov.au/getmedia/0f281915-2937-4015-a8d0-9abd3990f976/crdapcp.pdf.aspx?inline=true (accessed on 13 November 2020).
  40. Australian Bureau of Statistics (ABS). 4364.0.55.001 Australian Health Survey: First Results, 2011–2012; Australian Bureau of Statistics: Canberra, Australia, 2011.
  41. Rae, S.; Walker, D.D.; Attfield, M.D. Chronic bronchitis and dust exposure in British coalminers. In Inhaled Particles III; Walton, W.H., Ed.; Unwin Brothers: Surrey, UK, 1970; pp. 883–895. [Google Scholar]
  42. Marine, W.M.; Gurr, D.; Jacobsen, M. Clinically important respiratory effects of dust exposure and smoking in British coal miners. Am. Rev. Respir. Dis. 1988, 137, 106–112. [Google Scholar] [CrossRef] [PubMed]
  43. Bio, F.; Sadhra, S.; Jackson, C.; Burge, P. Respiratory symptoms and lung function impairment in underground gold miners in Ghana. Ghana Med. J. 2010, 41, 38–47. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  44. Abramson, M.; Matheson, M.; Wharton, C.; Sim, M. Prevalence of respiratory symptoms related to chronic obstructive pulmonary disease and asthma among middle aged and older adults. Respirology 2002, 7, 325–331. [Google Scholar] [CrossRef]
  45. Vermeulen, R.; Silverman, D.T.; Garshick, E.; Vlaanderen, J.; Portengen, L.; Steenland, K. Exposure-response estimates for diesel engine exhaust and lung cancer mortality based on data from three occupational cohorts. Environ. Health Perspect. 2014, 122, 172–177. [Google Scholar] [CrossRef]
  46. Friesen, M.C.; Coble, J.B.; Lu, W.; Shu, X.-O.; Ji, B.-T.; Xue, S.; Portengen, L.; Chow, W.-H.; Gao, Y.-T.; Yang, G.; et al. Combining a Job-Exposure Matrix with Exposure Measurements to Assess Occupational Exposure to Benzene in a Population Cohort in Shanghai, China. Ann. Occup. Hyg. 2011, 56, 80–91. [Google Scholar]
  47. Lavoué, J.; Vincent, R.; Gérin, M. Statistical Modelling of Formaldehyde Occupational Exposure Levels in French Industries, 1986–2003. Ann. Occup. Hyg. 2005, 50, 305–321. [Google Scholar]
  48. Burstyn, I.; Kromhout, H.; Kauppinen, T.; Heikkilä, P.; Boffetta, P. Statistical modelling of the determinants of historical exposure to bitumen and polycyclic aromatic hydrocarbons among paving workers. Ann. Occup. Hyg. 2000, 44, 43–56. [Google Scholar] [CrossRef] [Green Version]
  49. Peters, S.; Vermeulen, R.; Portengen, L.; Olsson, A.; Kendzia, B.; Vincent, R.; Savary, B.; Lavoué, J.; Cavallo, D.M.; Cattaneo, A.; et al. Modelling of occupational respirable crystalline silica exposure for quantitative exposure assessment in community-based case-control studies. J. Environ. Monit. 2011, 13, 3262–3268. [Google Scholar] [CrossRef]
  50. Althubaiti, A. Information bias in health research: Definition, pitfalls, and adjustment methods. J. Multidiscip. Healthc. 2016, 9, 211–217. [Google Scholar] [CrossRef] [PubMed] [Green Version]
Ijerph 17 08435 g001 550
Figure 1. Median elemental carbon concentration (solid line) and prevalence of any respiratory symptom (dotted line) of Western Australian miners, 2006–2012.
Figure 1. Median elemental carbon concentration (solid line) and prevalence of any respiratory symptom (dotted line) of Western Australian miners, 2006–2012.
Ijerph 17 08435 g001
Table
Table 1. Characteristics of the Western Australian miners, 2006–2012.
Table 1. Characteristics of the Western Australian miners, 2006–2012.
2006
N = 239
n = 239		2007
N = 388
n = 327		2008
N = 430
n = 351		2009
N = 507
n = 435		2010
N = 452
n = 390		2011
N = 381
n = 343		2012
N = 567
n = 513		Total
N = 2964
n = 2598
Age, mean (SD)35.3 (9.3)35.3 (9.8)34.8 (9.7)35.7 (9.6)34.7 (10.1)35.1 (10.7)33.9 (10.1)34.9 (9.9)
Sex, n (%)
    Female6 (2.5)15 (4.6)21 (5.9)12 (2.8)21 (5.4)23 (6.7)29 (5.6)127 (4.9)
    Male233 (97.5)312 (95.4)330 (94.0)423 (97.2)369 (94.6)320 (93.3)484 (94.3)2471 (95.1)
Occupation group, n (%)
    Surface production7 (2.9)10 (3.1)23 (6.6)21 (4.8)12 (3.1)34 (9.9)61 (11.9)168 (6.5)
    Underground mining232 (97.1)317 (96.9)328 (93.4)414 (95.2)378 (96.9)309 (90.1)452 (88.1)2430 (93.5)
Mask wearing, n (%)
    No219 (91.6)299 (91.4)308 (87.7)395 (90.8)356 (91.3)314 (91.5)451 (87.9)2342 (90.1)
    Yes20 (8.34)28 (8.6)43 (12.3)40 (9.2)34 (8.7)29 (8.5)62 (12.1)256 (9.9)
Shift length, n (%)
    12 h214 (89.5)281 (85.9)311 (88.6)389 (89.4)370 (94.9)313 (91.3)477 (93.0)2355 (90.6)
    8 h25 (10.5)46 (14.1)40 (11.4)46 (10.6)20 (5.2)30 (8.8)36 (7.0)243 (9.4)
Table
Table 2. Elemental carbon exposure of Western Australian miners by occupation group, mask wearing status, and work shift length, 2006–2012.
Table 2. Elemental carbon exposure of Western Australian miners by occupation group, mask wearing status, and work shift length, 2006–2012.
YearnOverallElemental Carbon Concentration (mg/m3)
Occupation GroupMask WearingShift Length
Surface ProductionUnderground MiningpYesNop8 h12 hp
2006239 7232 20219 25214
Median (IQR) 0.074 (0.067)0.09 (0.455)0.074 (0.066)0.1090.05 (0.037)0.076 (0.068)0.0090.072 (0.07)0.075 (0.067)0.884
2007327 10317 28299 46281
Median (IQR) 0.075 (0.085)0.053 (0.04)0.077 (0.085)0.1050.04 (0.05)0.079 (0.086)<0.0010.068 (0.093)0.077 (0.085)0.001
2008351 23328 43308 40311
Median (IQR) 0.066 (0.072)0.045 (0.024)0.07 (0.071)0.0010.05 (0.035)0.071 (0.074)0.0070.058 (0.106)0.067 (0.065)0.665
2009435 21414 40395 46389
Median (IQR) 0.07 (0.087)0.034 (0.019)0.073 (0.086)<0.0010.039 (0.055)0.073 (0.087)0.0040.06 (0.062)0.072 (0.086)0.004
2010390 12378 34356 20370
Median (IQR) 0.062 (0.065)0.041 (0.048)0.062 (0.065)0.1130.027 (0.04)0.066 (0.061)<0.0010.064 (0.064)0.062 (0.065)0.706
2011343 34309 29314 30313
Median (IQR) 0.063 (0.076)0.035 (0.046)0.065 (0.085)<0.0010.041 (0.04)0.065 (0.084)0.0010.057 (0.077)0.064 (0.075)0.447
2012513 61452 62451 36477
Median (IQR) 0.056 (0.077)0.037 (0.038)0.06 (0.078)<0.0010.04 (0.061)0.058 (0.079)0.070.105 (0.096)0.055 (0.068)0.087
Total2598 1682430 2562342 2432355
Median (IQR) 0.066 (0.073)0.038 (0.04)0.069 (0.076)<0.0010.04 (0.044)0.07 (0.077)<0.0010.066 (0.088)0.067 (0.073)0.521
Table
Table 3. Prevalence of respiratory symptoms of Western Australian miners, 2006–2012.
Table 3. Prevalence of respiratory symptoms of Western Australian miners, 2006–2012.
YearNRespiratory Symptom, n (%)
CoughPhlegmWheezeBreathlessnessAny
200623962 (25.9)33 (13.8)33 (13.8)41 (17.2)99 (41.4)
200732770 (21.4)38 (11.6)38 (11.6)31 (9.5)101 (30.9)
200835141 (11.7)39 (11.1)35 (10.0)33 (9.4)96 (27.4)
200943566 (15.2)57 (13.1)45 (10.3)48 (11.0)127 (29.2)
201039058 (14.9)52 (13.3)36 (9.2)31 (7.9)112 (28.7)
201134351 (14.9)39 (11.4)44 (12.8)29 (8.5)100 (29.2)
201251359 (11.5)45 (8.8)43 (8.4)36 (7.0)108 (21.1)
Total2598407 (15.7)303 (11.7)274 (10.5)249 (9.6)743 (28.6)
p-trend 0.0410.1590.1740.0410.029
Table
Table 4. Prevalence of respiratory symptoms by occupation group, mask wearing status, and work shift length (n = 2598).
Table 4. Prevalence of respiratory symptoms by occupation group, mask wearing status, and work shift length (n = 2598).
nRespiratory Symptom, n (%)
CoughPhlegmWheezeBreathlessnessAny
Occupation group
Surface production25326 (10.3)20 (7.9)26 (10.3)28 (11.1)61 (24.1)
Underground mining2345381 (16.2)283 (12.1)248 (10.6)221 (9.4)682 (29.1)
p 0.0170.0630.9690.4650.112
Mask wearing
No2342379 (16.2)279 (11.9)252 (10.8)227 (9.7)681 (29.1)
Yes25628 (10.9)24 (9.4)22 (8.6)22 (8.6)62 (24.2)
p 0.0360.2720.3350.6490.119
Shift length
12 h2355361 (15.3)274 (11.6)252 (10.7)225 (9.6)676 (28.7)
8 h24346 (18.9)29 (11.9)22 (9.1)24 (9.9)67 (27.6)
p 0.1680.9730.4930.9620.766
Smoking status
Smoker953264 (27.7)183 (19.2)153 (16.1)124 (13.0)404 (42.4)
Non-smoker1645143 (8.7)120 (7.3)121 (7.4)125 (7.6)339 (20.6)
p <0.001<0.001<0.001<0.001<0.001
Table
Table 5. Elemental carbon exposure and age of Western Australian miners by status of respiratory symptoms.
Table 5. Elemental carbon exposure and age of Western Australian miners by status of respiratory symptoms.
Status of Respiratory Symptomp
NoYes
Cough
n2191407
Age, mean (SD)33.8 (10.1)36.4 (9.96)<0.001
EC, median (IQR)0.065 (0.074)0.074 (0.079)0.018
Phlegm
n2295303
Age, mean (SD)33.9 (10.1)36.9 (9.49)<0.001
EC, median (IQR)0.065 (0.074)0.076 (0.074)0.019
Wheeze
n2324274
Age, mean (SD)33.9 (10.1)36.8 (9.48)<0.001
EC, median (IQR)0.066 (0.073)0.068 (0.073)0.826
Breathlessness
n2349249
Age, mean (SD)33.7 (9.88)39.6 (10.4)<0.001
EC, median (IQR)0.067 (0.073)0.066 (0.061)0.902
Any
n1855743
Age, mean (SD)33.3 (9.98)36.5 (9.98)<0.001
EC, median (IQR)0.065 (0.075)0.069 (0.07)0.062
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Rumchev, K.; Hoang, D.V.; Lee, A. Trends in Exposure to Diesel Particulate Matter and Prevalence of Respiratory Symptoms in Western Australian Miners. Int. J. Environ. Res. Public Health 2020, 17, 8435. https://doi.org/10.3390/ijerph17228435

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Rumchev K, Hoang DV, Lee A. Trends in Exposure to Diesel Particulate Matter and Prevalence of Respiratory Symptoms in Western Australian Miners. International Journal of Environmental Research and Public Health. 2020; 17(22):8435. https://doi.org/10.3390/ijerph17228435

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Rumchev, Krassi, Dong Van Hoang, and Andy Lee. 2020. "Trends in Exposure to Diesel Particulate Matter and Prevalence of Respiratory Symptoms in Western Australian Miners" International Journal of Environmental Research and Public Health 17, no. 22: 8435. https://doi.org/10.3390/ijerph17228435

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