Wood heater smoke and mortality in the Australian Capital Territory:a rapid health impact assessment

Objectives: To estimate the number of deaths and the cost of deaths attributable to wood heater smoke in the Australian Capital Territory. Study design: Rapid health impact assessment, based on fine particulate matter (PM2.5) data from three outdoor air pollution monitors and published exposure–response functions for natural cause mortality attributed to PM2.5 exposure. Setting: Australian Capital Territory (population, 2021: 454 000), 2016–2018, 2021, and 2022 (2019 and 2020 excluded because of the impact of extreme bushfires on air quality). Main outcome measures: Proportion of PM2.5 exposure attributable to wood heaters; numbers of deaths and associated cost of deaths (based on the value of statistical life: $5.3 million) attributable to wood heater smoke. Results: Wood heater emissions contributed an estimated 1.16–1.73 μg/m3 to the annual mean PM2.5 concentration during the three colder years (2017, 2018, 2021), or 17–25$57–136 million (most conservative exposure–response function) and $140–333 million (least conservative exposure–response function). Conclusions: The estimated annual number of deaths in the ACT attributable to wood heater PM2.5 pollution is similar to that attributed to the extreme smoke of the 2019–20 Black Summer bushfires. The number of wood heaters should be reduced by banning new installations and phasing out existing units in urban and suburban areas.</p

Evaluating portable air cleaner effectiveness in residential settings to reduce exposures to biomass smoke resulting from prescribed burns

AIM: Prescribed burning is the most common method employed to reduce fuel loads in flammable landscapes. This practice is designed to reduce the hazard associated with uncontrolled bushfires. Prescribed burns are frequently conducted close to residential areas, and the associated smoke impacts can adversely affect community health. Particulate matter is the predominant pollutant within the smoke and is strongly and consistently linked with adverse health effects. Outdoor smoke readily infiltrates buildings and reduces the quality of indoor air. Portable air cleaners containing high-efficiency particulate air (HEPA) filters are a promising indoor air quality intervention for reducing outdoor smoke exposure.METHODS: We provided 10 homes from semirural regions of Victoria, Australia, with HEPA cleaners and conducted continuous monitoring of indoor and outdoor fine particulate matter (PM2.5) for 2-4 weeks during prescribed burning periods. We calculated the potential improvements to indoor air quality when operating a HEPA cleaner during a smoke episode. Ventilation measures were conducted to identify points of smoke ingress and housing characteristics that could lead to higher infiltration rates.RESULTS: Depending on the house, the use of HEPA cleaners resulted in a reduction in indoor PM2.5 concentrations of 30-74%.CONCLUSIONS: HEPA cleaners have the potential to substantially improve indoor air quality during episodic smoke episodes.</p

Healthy country, healthy people: the relationship between Indigenous health status and "caring for country"

Objective: To investigate associations between &ldquo;caring for country&rdquo; &mdash; an activity that Indigenous peoples assert promotes good health &mdash; and health outcomes relevant to excess Indigenous morbidity and mortality.Design, setting and participants: Cross-sectional study involving 298 Indigenous adults aged 15&ndash;54 years in an Arnhem Land community, recruited from March to September 2005.Main outcome measures: Self-reported involvement in caring for country, health behaviours and clinically measured body mass index (BMI), waist circumference, blood pressure, type 2 diabetes status, albumin to creatinine ratio (ACR), levels of glycated haemoglobin (HbA1c) and high-density lipoprotein (HDL) cholesterol, lipid ratio, score on the five-item version of the Kessler Psychological Distress Scale (K5), and 5-year cardiovascular disease (CVD) risk.Results: Controlling for sociodemographic characteristics and health behaviours, multivariate regression revealed significant and substantial associations between caring for country and health outcomes. An interquartile range rise in the weighted composite caring-for-country score was significantly associated with more frequent physical activity, better diet, lower BMI (regression coefficient [b] = &minus; 2.83; 95% CI, &minus; 4.56 to &minus; 1.10), less abdominal obesity (odds ratio [OR], 0.43; 95% CI, 0.26&ndash;0.72), lower systolic blood pressure (b = &minus; 7.59; 95% CI, &minus; 12.01 to &minus; 3.17), less diabetes (OR, 0.12; 95% CI, 0.03&ndash;0.52), lower HbA1c level (b = &minus; 0.45; 95% CI, &minus; 0.79 to &minus; 0.11), non-elevated ACR (OR, 0.28; 95% CI, 0.13&ndash;0.60), higher HDL cholesterol level (b = 0.06; 95% CI, 0.01&ndash;0.12), lower K5 score (b = &minus; 0.97; 95% CI, &minus; 1.64 to &minus; 0.31) and lower CVD risk (b = &minus; 0.77; 95% CI, &minus; 1.43 to &minus; 0.11).Conclusions: Greater Indigenous participation in caring for country activities is associated with significantly better health. Although the causal direction of these associations requires clarification, our findings suggest that investment in caring for country may be a means to foster sustainable economic development and gains for both ecological and Indigenous peoples&rsquo; health

Heatwave and health impact research : a global review

Background Observed increases in the frequency and intensity of heatwave events, together with the projected acceleration of these events worldwide, has led to a rapid expansion in research on the health impacts of extreme heat. Objective To examine how research on heatwaves and their health-related impact is distributed globally. Methods A systematic review was undertaken. Four online databases were searched for articles examining links between specific historical heatwave events and their impact on mortality or morbidity. The locations of these events were mapped at a global scale, and compared to other known characteristics that influence heat-related illness and death. Results When examining the location of heatwave and health impact research worldwide, studies were concentrated on mid-latitude, high-income countries of low- to medium-population density. Regions projected to experience the most extreme heatwaves in the future were not represented. Furthermore, the majority of studies examined mortality as a key indicator of population-wide impact, rather than the more sensitive indicator of morbidity. Conclusion While global heatwave and health impact research is prolific in some regions, the global population most at risk of death and illness from extreme heat is under-represented. Heatwave and health impact research is needed in regions where this impact is expected to be most severe

The value of local heatwave impact assessment : a case-crossover analysis of hospital emergency department presentations in Tasmania, Australia

Heatwaves have been identified as a threat to human health, with this impact projected to rise in a warming climate. Gaps in local knowledge can potentially undermine appropriate policy and preparedness actions. Using a case-crossover methodology, we examined the impact of heatwave events on hospital emergency department (ED) presentations in the two most populous regions of Tasmania, Australia, from 2008–2016. Using conditional logistic regression, we analyzed the relationship between ED presentations and severe/extreme heatwaves for the whole population, specific demographics including age, gender and socio-economic advantage, and diagnostic conditions that are known to be impacted in high temperatures. ED presentations increased by 5% (OR 1.05, 95% CI 1.01–1.09) across the whole population, by 13% (OR 1.13, 95% CI 1.03–1.24) for children 15 years and under, and by 19% (OR 1.19, 95% CI 1.04–1.36) for children 5 years and under. A less precise association in the same direction was found for those over 65 years. For diagnostic subgroups, non-significant increases in ED presentations were observed for asthma, diabetes, hypertension, and atrial fibrillation. These findings may assist ED surge capacity planning and public health preparedness and response activities for heatwave events in Tasmania, highlighting the importance of using local research to inform local practice

Managing Extreme Heat and Smoke: A Focus Group Study of Vulnerable People in Darwin, Australia

Extreme heat and poor air quality arising from landscape fires are an increasing global concern driven by anthropogenic climate change. Previous studies have shown these environmental conditions are associated with negative health outcomes for vulnerable people. Managing and adapting to these conditions in a warming climate can present substantial difficulties, especially in climates already challenging for human habitation. This study was set in the tropical city of Darwin, Australia. We recruited individuals from population groups vulnerable to outdoor hazards: outdoor workers, teachers and carers, and sportspeople, to participate in focus group discussions. We aimed to gain an understanding of the impacts of extreme heat and poor air quality and how individuals perceived and managed these environmental conditions. We identified a number of key themes relating to impacts on health, work and activity, and adaptive behaviors, while identifying gaps in policy and infrastructure that could improve the lives and protect the health of vulnerable people living, working, and playing in this region. In addition, these outcomes potentially provide direction for other regions with similar environmental challenges. Extreme heat and poor air quality place an additional burden on the lives of people in high-risk settings, such as outdoor workers, teachers and carers, and sportspeople

Long-term exposure to low concentrations of air pollutants and hospitalisation for respiratory diseases:A prospective cohort study in Australia

Background: Short- and long-term spatiotemporal variation in exposure to air pollution is associated with respiratory morbidity in areas with moderate-to-high level of air pollution, but very few studies have examined whether these associations also exist in areas with low level exposure. Objectives: We assessed the association between spatial variation in long-term exposure to PM and NO and hospitalisation for all respiratory diseases, asthma, chronic obstructive pulmonary disease (COPD), and pneumonia, in older adults residing in Sydney, Australia, a city with low-level concentrations. Methods: We recorded data on hospitalisations for 100,084 participants, who were aged >45 years at entry in 2006–2009 until June 2014. Annual NO and PM concentrations were estimated for the participants’ residential addresses and Cox proportional hazards regression was used to model the association between exposure to air pollutants and first episode of hospitalisation, controlling for personal and area level covariates. We further investigated the shape of the exposure-response association and potential effect modification by age, sex, education level, smoking status, and BMI. Results: NO and PM annual mean exposure estimates were 17.5 μg·m and 4.5 μg·m respectively. NO and PM was positively, although not significantly, associated with asthma. The adjusted hazard ratio for a 1 μg·m increase in PM was 1.08, 95% confidence interval 0.89–1.30. The adjusted hazard ratio for a 5 μg·m increase in NO was 1.03, 95% confidence interval 0.88–1.19. We found no positive statistically significant associations with hospitalisation for all respiratory diseases, and pneumonia while negative associations were observed with COPD. Conclusions: We found weak positive associations of exposure to air pollution with hospitalisation for asthma while there was no evidence of an association for all respiratory diseases

Hilbert Spaces from Path Integrals

It is shown that a Hilbert space can be constructed for a quantum system starting from a framework in which histories are fundamental. The Decoherence Functional provides the inner product on this "History Hilbert space". It is also shown that the History Hilbert space is the standard Hilbert space in the case of non-relativistic quantum mechanics.Comment: 22 pages. Minor updates to match published versio

Ambient biomass smoke and cardio-respiratory hospital admissions in Darwin, Australia

<p>Abstract</p> <p>Background</p> <p>Increasing severe vegetation fires worldwide has been attributed to both global environmental change and land management practices. However there is little evidence concerning the population health effects of outdoor air pollution derived from biomass fires. Frequent seasonal bushfires near Darwin, Australia provide an opportunity to examine this issue. We examined the relationship between atmospheric particle loadings <10 microns in diameter (PM₁₀), and emergency hospital admissions for cardio-respiratory conditions over the three fire seasons of 2000, 2004 and 2005. In addition we examined the differential impacts on Indigenous Australians, a high risk population subgroup.</p> <p>Methods</p> <p>We conducted a case-crossover analysis of emergency hospital admissions with principal ICD10 diagnosis codes J00–J99 and I00–I99. Conditional logistic regression models were used to calculate odds ratios for admission with 10 μg/m³rises in PM₁₀. These were adjusted for weekly influenza rates, same day mean temperature and humidity, the mean temperature and humidity of the previous three days, days with rainfall > 5 mm, public holidays and holiday periods.</p> <p>Results</p> <p>PM₁₀ranged from 6.4 – 70.0 μg/m³(mean 19.1). 2466 admissions were examined of which 23% were for Indigenous people. There was a positive relationship between PM₁₀and admissions for all respiratory conditions (OR 1.08 95%CI 0.98–1.18) with a larger magnitude in the Indigenous subpopulation (OR1.17 95% CI 0.98–1.40). While there was no relationship between PM₁₀and cardiovascular admissions overall, there was a positive association with ischaemic heart disease in Indigenous people, greatest at a lag of 3 days (OR 1.71 95%CI 1.14–2.55).</p> <p>Conclusion</p> <p>PM10 derived from vegetation fires was predominantly associated with respiratory rather than cardiovascular admissions. This outcome is consistent with the few available studies of ambient biomass smoke pollution. Indigenous people appear to be at higher risk of cardio-respiratory hospital admissions associated with exposure to PM10.</p