Exposure to dust and respiratory health among Australian miners

Purpose: Occupational exposure to dust has been recognised as a significant health hazard to mine workers. This study aimed to investigate the association between exposure to inhalable (INH) and respirable (RES) dust and respiratory health among mine workers in Western Australia using an industry-wide exposure database. Methods: The database comprised cross-sectional surveys conducted by mining companies for the period 2001–2012. The study population consisted of 12,797 workers who were monitored for exposure to INH and RES dust and undertook health assessments including a respiratory questionnaire and spirometry test. Results: Despite the general trend of declining exposure to both INH and RES dust observed over the 12 years period, mine workers reported a higher prevalence of phlegm and cough when exposed to elevated concentrations of INH and RES dust. Logistic regression analysis further confirmed the positive association between INH dust exposure and the prevalence of phlegm with an adjusted odds ratio of 1.033 (95% CI 1.012–1.052). Overall, 6.3% of miners might have potential airway obstruction, and exposure to INH dust was associated with impaired lung function parameters. Conclusion: Exposure levels of INH and RES dust particles among mine workers have reduced considerably and were well below currently legislated occupational exposure limits. However, given the reported higher prevalence of phlegm and cough among those with elevated dust concentrations, there is a continued need for effective dust exposure monitoring and control in the mineral mining industry

Modelling the Spatio-Temporal Concentration of Diesel Particulate Matter in an Underground Mine

Diesel Particulate Matter (DPM) is an important pollutant, both in industrial areas and cities, and also in underground mines. DPM is essentially the carbonaceous aerosol emitted by diesel engines, with a primary particle size of 10-30 nm, though which rapidly agglomerates to form 100-300 nm aerosols. Most guidelines limit occupational exposure to DPM (measured as elemental carbon) to 100 μg/m3, on an 8-hr averaged basis. However directly assessing worker exposure is both time consuming and expensive. Apart from sampling the exposure of each individual worker, or conducting continuous (and expensive) monitoring, it is difficult to determine if the DPM levels in a workplace will be sufficient to cause DPM exposures above guideline levels. This work has developed a combined particle dynamics and Bayesian regression model, which allows the DPM levels in an underground mine to be predicted both spatially and temporally. The model incorporates known physical effects, (airflow conditions, dispersion, agglomeration), vehicle movement and vehicle emission rates. This enables the model to account for changing (increased) levels of productivity in the mine, a change in the vehicle fleet, or other such factors. The model has been validated against a monitoring study performed in the mine

The association between indoor air quality and adult blood pressure levels in a high-income setting

Background: Indoor air pollution is still considered one of the leading causes of morbidity and mortality worldwide. We aimed to investigate the potential association between indoor particulate matter (PM) and fasting clinic blood pressure in adult Australians. Methods: Sixty-three participants residing within the Perth metropolitan area were studied. Participants were aged between 18 and 65 years and free of major medical conditions. We conducted 24-h monitoring of residential PM concentrations, including the size fractions PM1, PM2.5, PM4, and PM10. All participants attended a clinical assessment at Curtin University following a 10–12 h overnight fast. Results: In this study we found that PM1 and PM2.5 were significantly associated with heart rate: a one interquartile range (IQR) increase in PM1 or PM2.5 was associated with a 4–6 beats per minute (bpm) increase in heart rate. Both PM10 and total PM exposure had a significant impact on systolic blood pressure (SBP): a one IQR increase in PM10 and total PM were associated with a 10 mmHg (95% CI: 0.77–20.05) and 12 mmHg (2.28–22.43 mmHg) increase in SBP, respectively. Conclusion: The study findings provide additional support to the thesis that indoor air pollution is an important modifiable factor in the risk of hypertension

The Association between Exposure to Residential Indoor Volatile Organic Compounds and Measures of Central Arterial Stiffness in Healthy Middle-Aged Men and Women

It is well reported that individuals spend up to 90% of their daily time indoors, with between 60% to 90% of this time being spent in the home. Using a cross-sectional study design in a population of 111 healthy adults (mean age: 52.3 ± 9.9 years; 65% women), we investigated the association between exposure to total volatile organic compounds (VOCs) in indoor residential environments and measures of central arterial stiffness, known to be related to cardiovascular risk. Indoor VOC concentrations were measured along with ambulatory measures of pulse pressure (cPP), augmentation index (cAIx) and cAIx normalized for heart rate (cAIx75 ), over a continuous 24-h period. Pulse wave velocity (cfPWV) was determined during clinical assessment. Multiple regression analysis was performed to examine the relationship between measures of arterial stiffness and VOCs after adjusting for covariates. Higher 24-h, daytime and night-time cAIx was associated with an interquartile range increase in VOCs. Similar effects were shown with cAIx75 . No significant effects were observed between exposure to VOCs and cPP or cfPWV. After stratifying for sex and age (≤50 years; >50 years), effect estimates were observed to be greater and significant for 24-h and daytime cAIx in men, when compared to women. No significant effect differences were seen between age groups with any measure of arterial stiffness. In this study, we demonstrated that residential indoor VOCs exposure was adversely associated with some measures of central arterial stiffness, and effects were different between men and women. Although mechanistic pathways remain unclear, these findings provide a possible link between domestic VOCs exposure and unfavourable impacts on individual-level cardiovascular disease risk

Residential indoor exposure to fine and ultrafine particulate air pollution in association with blood pressure and subclinical central haemodynamic markers of cardiovascular risk among healthy adults living in Perth, Western Australia

Despite that large percentages of individual daily time is spent in the home, few studies have examined the relationship between indoor particulate matter (PM) exposure in residential settings with subclinical indicators of cardiovascular risk. This cross-sectional study investigated associations between exposure to fine (PM2.5) and ultrafine (UFP) PM in domestic indoor environments, with central blood pressure (BP) and component BP measures (pulse pressure, augmented pressure [AP], augmentation index [AIx], mean arterial pressure, pulse wave velocity [PWV]) in 40 non-smoking, otherwise healthy adults (58% women) living in Perth, Western Australia. Overall, in adjusted models, an interquartile range (IQR) increase in PM2.5 was associated with a 3.2 mmHg (95% confidence interval [CI]: 0.99, 5.45) higher diastolic BP, and a 1.8 mmHg lower AP (95%CI: − 3.63, − 0.01) and 0.4 m/s PWV (95%CI: − 0.80, − 0.08), respectively. For the UFP fraction, an IQR increase was associated with a 5.2% higher AIx (95%CI: 0.51, 9.97) and a 0.6 m/s lower PWV (95%CI: − 1.00, − 0.11). When stratified by sex, higher UFP concentrations were associated with higher DBP and lower PWV among women. Among men, higher UFP concentrations were associated with lower AP. Exposure to domestic indoor fine and ultrafine PM was associated with preclinical indicators of cardiovascular risk and some of these relationships were affected by sex. These findings contribute important evidence linking low-level residential indoor PM exposure with measurable impacts on cardiovascular physiology and may inform preventative recommendations as part of risk profiles for susceptible individuals

Associations between sub-clinical markers of cardiometabolic risk and exposure to residential indoor air pollutants in healthy adults in Perth, Western Australia: A study protocol

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. Background: A growing body of epidemiological and clinical evidence has implicated air pollution as an emerging risk factor for cardiometabolic disease. Whilst individuals spend up to two-thirds of daily time in their domestic residential environment, very few studies have been designed to objectively measure the sub-clinical markers of cardiometabolic risk with exposure to domestic indoor air pollutants. This cross-sectional study aims to investigate associations between the components of domestic indoor air quality and selected sub-clinical cardiometabolic risk factors in a cohort of healthy adults living in Perth,Western Australia. Methods: One hundred and eleven non-smoking adults (65% female) living in non-smoking households who were aged between 35-69 years were recruited for the project. Study subjects were invited to participate in all sections of the study, which included: Domestic indoor air monitoring along with the concurrent 24 h ambulatory monitoring of peripheral and central blood pressure and measures of central hemodynamic indices, standardized questionnaires on aspects relating to current health status and the domestic environment, a 24 h time-activity diary during the monitoring period, and clinic-based health assessment involving collection of blood and urine biomarkers for lipid and glucose profiles, as well as measures of renal function and an analysis of central pulse wave and pulse wave velocity. Results: This study provides a standardized approach to the study of sub-clinical cardiometabolic health effects that are related to the exposure to indoor air pollution. Conclusion: The findings of this study may provide direction for future research that will further contribute to our understanding of the relationship that exists between indoor air pollution and sub-clinical markers of cardiometabolic risk

Snoring in primary school children and domestic environment: A Perth school based study

BACKGROUND: The home is the predominant environment for exposure to many environmental irritants such as air pollutants and allergens. Exposure to common indoor irritants including volatile organic compounds, formaldehyde and nitrogen dioxide, may increase the risk of snoring for children. The aim of this study was to investigate domestic environmental factors associated with snoring in children. METHODS: A school-based respiratory survey was administered during March and April of 2002. Nine hundred and ninety six children from four primary schools within the Perth metropolitan area were recruited for the study. A sub-group of 88 children aged 4–6 years were further selected from this sample for domestic air pollutant assessment. RESULTS: The prevalences of infrequent snoring and habitual snoring in primary school children were 24.9% and 15.2% respectively. Passive smoking was found to be a significant risk factor for habitual snoring (odds ratio (OR) = 1.77; 95% confidence interval (CI): 1.20–2.61), while having pets at home appeared to be protective against habitual snoring (OR = 0.58; 95% CI: 0.37–0.92). Domestic pollutant assessments showed that the prevalence of snoring was significantly associated with exposure to nitrogen dioxide during winter. Relative to the low exposure category (<30 μg/m(3)), the adjusted ORs of snoring by children with medium (30 – 60 μg/m(3)) and high exposures (> 60 μg/m(3)) to NO(2 )were 2.5 (95% CI: 0.7–8.7) and 4.5 (95% CI: 1.4–14.3) respectively. The corresponding linear dose-response trend was also significant (P = 0.011). CONCLUSION: Snoring is common in primary school children. Domestic environments may play a significant role in the increased prevalence of snoring. Exposure to nitrogen dioxide in domestic environment is associated with snoring in children

Assessing employees perception on health and safety management in public hospitals

This article examined the perception of employees regarding the management of Occupational Health and Safety (OHS) in public hospital in Malaysia.418 employees from three state hospitals in the northern region of Malaysia participated in this study and that gave a response rate of 43.15%. Data was collected using a set of questionnaires which consists of variables including safety satisfaction and feedback, safety communication, role of supervisor, work pressure, training and competence, management commitment, safety involvement, safety objectives, safety reporting, and leadership style.Data analysis was done using descriptive statistics, t-test, one-way ANOVA, Pearson correlation and multiple regressions.Findings showed that employees perceived safety reporting as the most important dimension and work pressure as the least important component in the OHS practices in their workplaces.Empirical evidence indicated that there was no significant difference in safety satisfaction and feedback between male and female workers but there was a significant difference among these employees in safety involvement.In addition, results also showed that there was a significant difference in safety satisfaction faced by job position like nurse but there was no significant difference between employees with job tenure comprise of less than 1 year, 2 to 15 years, and 16 years and above.Findings suggested that there was a significant positive correlation between safety satisfaction and feedback and safety communication, safety involvement, training and competence, safety reporting, work pressure, safety objectives, management commitment, role of supervisors, and leadership style.Regression analysis revealed approximately 54.5% (R2 = 0.545) of variance in safety satisfaction and feedback, that was simultaneously explained by five independent variables including safety involvement, safety reporting, work pressure, management commitment, and safety objectives