Bushfire Smoke Research Articles

Can digital technology help reduce smoke exposure and protect health in extreme air quality events?

Abstract Background In the southern hemisphere summer of 2019-2020, Australia experienced its most severe bushfire season on record. Smoke from fires affected 80% of the population, with large exceedances of the Australian National Air Quality Standard for particulate air pollution recorded in all major population centres during this period. We examined if emerging and innovative digital technology can assist extreme smoke-affected populations to reduce their exposure and protect their health. Methods AirRater is a free smartphone app that tracks air quality and user symptoms in near real-time. We distributed an online survey to over 13,000 app users to assess how they used this information during the 2019-20 bushfire season, and if the app was helpful in decision-making around reducing personal smoke exposure. Results We received responses from 1732 users (13.3%). Respondents reported that the app was highly useful, supporting informed decisions regarding daily activities during the smoke-affected period. Commonly reported activities supported by information provided through the app were staying inside (76%), rescheduling or planning outdoor activities (64%), changing locations to less affected areas (29%) and informing decisions on medication use (15%). Conclusions Smartphone apps enable users to reduce smoke exposure and protect their health by providing individual-level and location-specific data. Furthermore, digital technology such as AirRater provides the potential to provide insight into the community impacts of environmental hazards such as bushfire smoke. Key messages Smartphone apps enable users to reduce their smoke exposure and protect their health. These emerging technologies can help public health authorities to understand the community impact of environmental hazards.

Take My Breath Away

This article eschews the singularity of much disaster, crisis and catastrophe research to focus on the complex dynamics of convergent crises. It examines the prolonged crises of a summer of bushfire and COVID-19 which converged in Eurobodalla Shire on the south coast of New South Wales (NSW), Australia, in 2019–2020. We focus on air and breathing on the one hand and kinship and the social organisation of survival and recovery on the other. During Australia’s summer of bushfires, thick smoke rendered air, airways and breathing a challenge, leaving people open to reflection as well as to struggle. Bushfire smoke created ‘aware breathers’. It was aware breathers who were then to experience the invisible and separating threat of COVID-19. These convergent crises impacted the ‘mutuality of being’ of kinship (after Marshall Sahlins) and the social organisation of survival. Whereas the bushfires in Eurobodalla drew on grandparent-families in survival, the social distancing and lockdown of COVID-19 has cleaved these multi-household families asunder, at least for now. COVID-19 has also made plain how the mingling of breath is a new index of intimacy.

Reflections on the Catastrophic 2019–2020 Australian Bushfires

Reflections on the Catastrophic 2019–2020 Australian Bushfires

Efforts to control air pollution in the Asia-Pacific region.

Efforts to control air pollution in the Asia-Pacific region.

Health impacts of bushfire smoke exposure in Australia

Smoke exposure from bushfires, such as those experienced in Australia during 2019-2020, can reach levels up to 10 times those deemed hazardous. Short-term and extended exposure to high levels of air pollution can be associated with adverse health effects, although the most recent fires have brought into sharp focus that several important knowledge gaps remain. In this article, we briefly identify and discuss the existing Australian evidence base and make suggestions for future research.

Bushfire smoke: urgent need for a national health protection strategy.

This research was undertaken with support from the Australian National University College of Health and Medicine, and the assistance of resources from the Centre for Air pollution, energy and health Research (CAR). We used the CAR Data and Analysis Technology platform (https://cardat.github.io) to analyse data

Removal of Volatile Phenols From Wine Using Crosslinked Cyclodextrin Polymers.

Volatile phenols have been implicated as contributors to off-odors associated with taints from bushfire smoke and microbial spoilage. Various methods for the amelioration of off-odors have been evaluated, but to date, they have not included cyclodextrin (CD) polymers. In the current study, two CD polymers were prepared from β- and γ-CD, using hexamethylene diisocyanate (HDI) as a crosslinking agent. Adsorption tests were performed with four volatile phenols (guaiacol, 4-methylguaiacol, 4-ethylguaiacol and 4-ethylphenol) at concentrations up to 1 mg/L. The removal of volatile phenols by CD polymers achieved equilibrium almost instantly, with isotherm tests suggesting an adsorption capacity of 20.7 µg of volatile phenol per gram of polymer. Langmuir and Freundlich models were subsequently used to fit the data. In batch adsorption tests, the CD polymers achieved 45 to 77% removal of volatile phenols. Polymer reusability was also evaluated and was found to be excellent. A comparison between volatile phenol adsorption by CDs vs. CD polymers, determined using a novel four-phase headspace solid-phase microextraction (HS-SPME) method for gas chromatography-mass spectrometry (GC-MS), suggests CD polymers offer several advantages for use by the wine industry.

Efficacy of dexamethasone, salbutamol, and reduced respirable particulate concentration on aerobic capacity in horses with smoke-induced mild asthma.

BackgroundMild asthma in horses decreases racing performance and impairs gas exchange. The efficacy of treatment on performance is unknown.HypothesisTreatment targeting lung inflammation improves V˙O2peak in horses with mild asthma.AnimalsThoroughbred polo horses (n = 12) with smoke‐induced mild asthma. Horses were exposed to increased ambient particulate matter (35.51 μg/m3 [PM2.5]; day mean, centrally measured) from day −33 to 0, from bushfire smoke (natural model).MethodsProspective, randomized, placebo‐controlled, double‐blinded clinical trial. All horses completed 3 V˙O2peak tests, measuring aerobic and anaerobic variables: day 0 ‐baseline; day 16 ‐after dexamethasone (20 mg IM q24h; DEX, n = 6) or saline treatment (SALINE, n = 6), under improved ambient PM2.5 concentrations (7.04 μg/m3); day 17‐15‐30mins after inhaled salbutamol (1500 μg). Bronchoalveolar lavage and mucus scoring were performed on day −8 and day 20. Linear mixed effects models were used to examine the effects of timepoint and treatment group on BAL differential cell counts, mucus scores, aerobic and anaerobic variables.ResultsHorses’ mucus scores improved significantly from day −8 to 20 by 1.27 ± .38 (P = .01). There was a significant increase in V˙O2peak of 15.5 ± 4.0 mL(min.kg)−1 from day 0 to 17 (P = .002), representing an average (mean) increase in V˙O2peak of 13.2%. There was no difference in V˙O2peak between treatment groups (SALINE versus DEX) at any timepoint.Conclusions and Clinical ImportanceThis study highlighted the key role of improved air quality on functionally important airway inflammation. Evidence provided is central to increasing owner compliance regarding improved air quality for the treatment and prevention of mild asthma.

Bushfires in Australia: a serious health emergency under climate change

Bushfires in Australia: a serious health emergency under climate change

Australia burning

Australia burning

Comparing Air Pollution Modelling and Monitoring for Bushfire Smoke Health Impact Assessment in Australia

Comparing Air Pollution Modelling and Monitoring for Bushfire Smoke Health Impact Assessment in Australia

Bushfire smoke is pro-inflammatory and suppresses macrophage phagocytic function

Bushfires are increasing in frequency and severity worldwide. Bushfire smoke contains organic/inorganic compounds including aldehydes and acrolein. We described suppressive effects of tobacco smoke on the phagocytic capacity of airway macrophages, linked to secondary necrosis of uncleared apoptotic epithelial cells, persistence of non-typeable H. influenzae (NTHi), and inflammation. We hypothesised that bushfire smoke extract (BFSE) would similarly impair macrophage function. THP-1 or monocyte-derived macrophages (MDM) were exposed to 1–10% BFSE prepared from foliage of 5 common Australian native plants (genus Acacia or Eucalyptus), or 10% cigarette smoke extract (CSE). Phagocytic recognition receptors were measured by flow cytometry; pro-inflammatory cytokines and caspase 1 by immunofluorescence or cytometric bead array; viability by LDH assay; and capsase-3/PARP by western blot. BFSE significantly decreased phagocytosis of apoptotic cells or NTHi by both THP-1 macrophages and MDM vs air control, consistent with the effects of CSE. BFSE significantly decreased MDM expression of CD36, CD44, SR-A1, CD206 and TLR-2 and increased active IL-1β, caspase-1 and secreted IL-8. BFSE dose-dependently decreased THP-1 macrophage viability (5-fold increase in LDH at 10%) and significantly increased active caspase-3. BFSE impairs macrophage function to a similar extent as CSE, highlighting the need for further research, especially in patients with pre-existing lung disease.

Glucosylation of Smoke-Derived Volatiles in Grapevine (Vitis vinifera) is Catalyzed by a Promiscuous Resveratrol/Guaiacol Glucosyltransferase.

Vinification of grapes (Vitis vinifera) exposed to forest fire smoke can yield unpalatable wine due to the presence of taint compounds from smoke and the release of smoke derived volatiles from their respective glycosides during the fermentation process or in-mouth during consumption. To identify glycosyltransferases (GTs) involved in the formation of glycosidically bound smoke-derived volatiles we performed gene expression analysis of candidate GTs in different grapevine tissues. Second, substrates derived from bushfire smoke or naturally occurring in grapes were screened with the candidate recombinant GTs. A resveratrol GT (UGT72B27) gene, highly expressed in grapevine leaves and berries was identified to be responsible for the production of the phenolic glucosides. UGT72B27 converted the stilbene trans-resveratrol mainly to the 3-O-glucoside. Kinetic analyses yielded specificity constants (kcat/KM) of 114, 17, 9, 8, and 2 mM-1 s-1 for guaiacol, trans-resveratrol, syringol, methylsyringol, and methylguaiacol, respectively. This knowledge will help to design strategies for managing the risk of producing smoke-affected wines.

Health effects of smoke from planned burns: a study protocol.

BackgroundLarge populations are exposed to smoke from bushfires and planned burns. Studies investigating the association between bushfire smoke and health have typically used hospital or ambulance data and been done retrospectively on large populations. The present study is designed to prospectively assess the association between individual level health outcomes and exposure to smoke from planned burns.Methods/designA prospective cohort study will be conducted during a planned burn season in three locations in Victoria (Australia) involving 50 adult participants who undergo three rounds of cardiorespiratory medical tests, including measurements for lung inflammation, endothelial function, heart rate variability and markers of inflammation. In addition daily symptoms and twice daily lung function are recorded. Outdoor particulate air pollution is continuously measured during the study period in these locations. The data will be analysed using mixed effect models adjusting for confounders.DiscussionPlanned burns depend on weather conditions and dryness of ‘fuels’ (i.e. forest). It is potentially possible that no favourable conditions occur during the study period. To reduce the risk of this occurring, three separate locations have been identified as having a high likelihood of planned burn smoke exposure during the study period, with the full study being rolled out in two of these three locations. A limitation of this study is exposure misclassification as outdoor measurements will be conducted as a measure for personal exposures. However this misclassification will be reduced as participants are only eligible if they live in close proximity to the monitors.

Characterization of primary and secondary organic aerosols in Melbourne airshed: The influence of biogenic emissions, wood smoke and bushfires

Detailed chemical characterisation was performed for wintertime and summertime PM10 samples collected in Melbourne, Australia. The samples were analysed for marker compounds of biomass burning and biogenic secondary organic aerosol (SOA). The chemical analysis showed that the site was significantly influenced by the emissions from wintertime domestic wood combustion and summertime bushfires. Monosaccharide anhydrides were major primary biomass burning marker compounds found in the samples with the average concentrations of 439, 191, 57 and 3630 ngm−3 for winter 2004, winter 2005, summer 2005 and summer 2006, respectively. The highest concentration was determined during the summer 2006 bushfire season with the concentration of 15,400 ngm−3. Biomass burning originating SOA compounds detected in the samples include substituted nitrophenols, mainly 4-nitrocatechol (Mr 155), methyl-nitrocatechols (Mr 169) and dimethyl-nitrocatechols (Mr 183) with the sum concentrations as high as 115 ngm−3 for the wintertime samples and 770 ngm−3 for the bushfire influenced samples. In addition to this, elevated levels of biogenic SOA marker compounds were determined in the summertime samples influence by bushfire smoke. These marker compounds can be categorised into carboxylic acid marker compounds and heteroatomic organic acids containing nitrogen and sulfur. Carboxylic acid marker compounds can be largely attributed to oxidation products originating from 1,8-cineole, α-pinene and β-pinene that are main constituents of eucalyptus VOC emissions. Among those, diaterpenylic acid, terpenylic acid and daterebic acid were found at elevated levels in the bushfire influenced samples. Heteroatomic monoterpene SOA marker compounds (Mr 295, C10H17NO7S) were detected during both winter and summer periods. Especially high levels of these compounds were determined in the severe bushfire samples from summer 2006. Based on the results obtained from the chemical analysis and a macro tracer method, we estimated that 1,8-cineole SOA alone contributed up to 3.5% of secondary organic carbon mass during the bushfire period in 2006. It is likely that biogenic VOC oxidation can be an important source of biomass burning organic aerosol mass.

Influence of fruit maturity at harvest on the intensity of smoke taint in wine.

Bushfire smoke can affect the composition and sensory properties of grapes and wines, in some cases leading to wines which exhibit undesirable “smoky”, “ashy” and “medicinal” characters. This study investigated the extent to which fruit maturity (i.e., ripeness) influences the perception of smoke taint in wine. Two white grape varieties (Chardonnay and Sauvignon Blanc) and two red grape varieties (Merlot and Shiraz) were exposed to smoke under experimental conditions, at approximately seven days post-veraison. Fruit was then harvested at two levels of maturity: Harvest A, when total soluble solids were 16–20 °Brix, i.e., the berry ripeness typically required for production of sparkling or light-bodied wines; and Harvest B, when total soluble solids were 22–25 °Brix, i.e., the berry ripeness typically required for production of full-bodied wines. The intensity of smoke taint in resulting wines was found to be influenced by fruit maturity, but differed between grape varieties. Smoke-related sensory attributes were apparent in Sauvignon Blanc wine made from early-harvested fruit and in Chardonnay wine made from late-harvested fruit, only; whereas Merlot and Shiraz wines exhibited smoke taint irrespective of fruit maturity. Smoke-derived volatile phenols, and various alcohols, esters and acids, were also quantified to determine the impact of smoke exposure and fruit maturity respectively, on wine composition.

Low cardiovascular risk subjects are more susceptible to microvascular dysfunction from bushfire air pollution

Background:Endothelialdysfunction (ED) is a likelymechanism for cardiovascular events fromair pollution.We sought the most sensitive marker for ED from bushfire-smoke and any interaction with cardiovascular (CV) risk factors (RF). Methods: We examined 55 community dwellers during bushfire smoke and clean air conditions (Smoke /Clean) and 10 controls during two clean-air conditions (Clean x2). Patients were divided into 2 groups based on their RF; low risk: thosewho had≤1 RF (male, hypertension, diabetes, dyslipidaemia and history of smoking) and high risk (those ≥2 RF). ED was assessed by flow-mediated dilatation (FMD), hyperaemic velocity time integral (VTI) and reactive hyperaemic index (RHI) by EndoPAT. Results: Daily PM10 levels (national standard <50 g/m3[Max]) during smoke-exposure were 123.2±63 /m3 (Max. 249), whereas they were 2.3±1.1 (4.8) in clean air. Although there were no significant differences in RHI and FMD (Figure), only the patients with low CV risk showed significant deterioration in VTI compared with clean air condition (65±24 cm, 81±21, p=0.013) but no change in high risk group (p=0.31). Conclusion: RHI and FMD remained similar between smoke and clean-air conditions irrespective of number of CV risk factors. However, microvascular dysfunction assessed by hyperaemic VTI deteriorates during the exposure from bushfire smoke in those with low CV risk. http://dx.doi.org/10.1016/j.hlc.2015.06.034

Response to Fay Johnston and David Bowman (2013), ‘Bushfire Smoke: An Exemplar of Coupled Human and Natural Systems’

Response to Fay Johnston and David Bowman (2013), ‘Bushfire Smoke: An Exemplar of Coupled Human and Natural Systems’

Bushfires, Human Health Economics, and Pyrogeography

AbstractBushfires (landscape fires) are a key Earth system process that affects humans and our societies and economies. In a recent article, we explored the coupling of humans to landscape fire through the lens of human health impacts of bushfire smoke. We noted that such an approach demands recognition of the indirect impacts and costs of bushfires that cannot be captured by simplistic proxies such as deaths directly attributable to a fire front. Evaluation of direct and indirect economic costs of bushfire disasters, and bushfire fire management remains a poorly developed research frontier that demands collaboration of expertise from a broad cross‐section of fields that often have limited experience of collaborating together. The need for such synthetic thinking about fire's place on Earth has spawned the discipline of pyrogeography.

Bushfire Smoke: An Exemplar of Coupled Human and Natural Systems

AbstractCarbon‐based microscopic particles have provided a crucial line of evidence in understanding the coupling between humans and fires. Through the sedimentary record, they have informed our understandings of the patterns of climate and humans on fire activity through time. The extent of contemporary atmospheric biomass burning emissions has become apparent through satellite monitoring, motivated by concerns about the effect on the climate system. Sophisticated monitoring techniques designed to monitor industrial pollution have provided a data stream useful to determine the impacts on human health of wildfire smoke: we review this rapidly expanding field. The key findings are that biomass smoke is quantitatively and qualitatively different from urban air pollution and that there is no ‘safe’ level of biomass smoke exposure. Managing fires and smoke impacts will become increasingly challenging as the climate continues to warm and demands understanding the trade‐off between wildfire and planned burns. The health impacts from severe smoke events are substantial when large populations are affected resulting in measurable increases in illness, hospital admissions, and deaths. The health impacts are not evenly distributed, and large segments of the population fall into higher risk groups. People in these categories are also likely to be adversely affected by the comparatively minor episodes of pollution generated by smaller planned burns. Planned burns thus need active programmes of public communication and air quality monitoring to ensure that the overall public health benefits of the intervention can be achieved with the minimum possible adverse impacts on higher risk individuals.