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Polar environments are among the fastest changing regions on the planet. It is a crucial time to make significant improvements in our understanding of how ocean and ice biogeochemical processes are linked with the atmosphere. This is especially true over Antarctica and the Southern Ocean where observations are severely limited and the environment is far from anthropogenic influences. In this commentary, we outline major gaps in our knowledge, emerging research priorities, and upcoming opportunities and needs. We then give an overview of the large-scale measurement campaigns planned across Antarctica and the Southern Ocean in the next 5 years that will address the key issues. Until we do this, climate models will likely continue to exhibit biases in the simulated energy balance over this delicate region. Addressing these issues will require an international and interdisciplinary approach which we hope to foster and facilitate with ongoing community activities and collaborations

Polar environments are among the fastest changing regions on the planet. It is a crucial time to make significant improvements in our understanding of how ocean and ice biogeochemical processes are linked with the atmosphere. This is especially true over Antarctica and the Southern Ocean where observations are severely limited and the environment is far from anthropogenic influences. In this commentary, we outline major gaps in our knowledge, emerging research priorities, and upcoming opportunities and needs. We then give an overview of the large-scale measurement campaigns planned across Antarctica and the Southern Ocean in the next 5 years that will address the key issues. Until we do this, climate models will likely continue to exhibit biases in the simulated energy balance over this delicate region. Addressing these issues will require an international and interdisciplinary approach which we hope to foster and facilitate with ongoing community activities and collaborations.

Coral reefs have been found to produce the sulfur compound dimethyl sulfide (DMS), a climatically relevant aerosol precursor predominantly associated with phytoplankton. Until recently, the role of coral-reef-derived DMS within the climate system had not been quantified. A study preceding the present work found that DMS produced by corals had negligible long-term climatic forcing at the global-regional scale. However, at sub-daily timescales more typically associated with aerosol and cloud formation, the influence of coral-reef-derived DMS on local aerosol radiative effects remains unquantified. The Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) has been used in this work to study the role of coral-reef-derived DMS at sub-daily timescales for the first time. WRF-Chem was run to coincide with an October 2016 field campaign over the Great Barrier Reef, Queensland, Australia, against which the model was evaluated. After updating and scaling the DMS surface water climatology, the model reproduced DMS and sulfur concentrations well. The inclusion of coral-reef-derived DMS resulted in no significant change in sulfate aerosol mass or total aerosol number. Subsequently, no direct or indirect aerosol effects were detected. The results suggest that the co-location of the Great Barrier Reef with significant anthropogenic aerosol sources along the Queensland coast prevents coral-reef-derived aerosol from having a modulating influence on local aerosol burdens in the current climate.

Background: The health effects of e-cigarettes in patients with pre-existing lung disease are unknown. The aim of this study was to investigate whether aerosols from a fourth-generation e-cigarette produces similar in-vitro cytotoxic, DNA damage and inflammatory effects on bronchial epithelial cells (BECs) from patients with COPD, as cigarette smoke. Methods: BECs from patients with COPD who underwent surgery for lung cancer and comparator (immortalised 16HBE) cells were grown at air liquid interface (ALI). BECs were exposed to aerosols from a JUUL® e-cigarette (Virginia Tobacco and Menthol pods at 5% nicotine strength) or reference 3R4F cigarette for 30 min at ALI. Cell cytotoxicity, DNA damage and inflammation were measured. Results: In response to the Virginia Tobacco and Menthol flavoured e-cigarette aerosols, COPD BECs showed comparable LDH release (cell cytotoxicity, p = 0.59, p = 0.67 respectively), DNA damage (p = 0.41, p = 0.51) and inflammation (IL-8, p = 0.20, p = 0.89 and IL-6, p = 0.24, p = 0.93), to cigarette smoke. 16HBE cells also showed comparable cellular responses to cigarette smoke. Conclusion: In airway cells from patients with COPD, aerosols from a fourth-generation e-cigarette were associated with similar toxicity to cigarette smoke. These results have potential implications for the safety of e-cigarette use in patients with lung disease.

Chemistry for Health Sciences (CZB190) is a first year prerequisite for all biochemistry subjects at QUT. In addition, CZB190 develops laboratory-based experimental skills and reasoning. With a cohort of over 220 students, the shift to at-home learning due to COVID-19 was a mammoth task for CZB190 staff and students. We want to showcase how our effective collaboration as lecturers, sessional academics and centralised learning support staff resulted in a supportive experience for CZB190 students as they adapted to the online chemistry classroom.

Cloud-radiation interactions over the Southern Ocean are not well constrained in climate models, in part due to uncertainties in the sources, concentrations, and cloud-forming potential of aerosol in this region. To date, most studies in this region have reported measurements from fixed terrestrial stations or a limited set of instrumentation and often present findings as broad seasonal or latitudinal trends. Here, we present an extensive set of aerosol and meteorological observations obtained during an austral summer cruise across the full width of the Southern Ocean south of Australia. Three episodes of continental-influenced air masses were identified, including an apparent transition between the Ferrel atmospheric cell and the polar cell at approximately 64span classCombining double low line"inline-formula"  S, and accompanied by the highest median cloud condensation nuclei (CCN) concentrations, at 252 cmspan classCombining double low line"inline-formula"-3. During the other two episodes, synoptic-scale weather patterns diverted air masses across distances greater than 1000 km from the Australian and Antarctic coastlines, respectively, indicating that a large proportion of the Southern Ocean may be periodically influenced by continental air masses. In all three cases, a highly cloud-active accumulation mode dominated the size distribution, with up to 93 % of the total number concentration activating as CCN. Frequent cyclonic weather conditions were observed at high latitudes and the associated strong wind speeds led to predictions of high concentrations of sea spray aerosol. However, these modelled concentrations were not achieved due to increased aerosol scavenging rates from precipitation and convective transport into the free troposphere, which decoupled the air mass from the sea spray flux at the ocean surface. CCN concentrations were more strongly impacted by high concentrations of large-diameter Aitken mode ae

This manuscript details the application of a profluorescent nitroxide (PFN) for the online quantification of radical concentrations on particulate matter (PM) using an improved Particle Into Nitroxide Quencher (PINQ). A miniature flow-through fluorimeter developed specifically for use with the 9,10-bis(phenylethynyl)anthracene-nitroxide (BPEAnit) probe was integrated into the PINQ, along with automated gas phase corrections through periodic high efficiency particle arrestor (HEPA) filtering. The resulting instrument is capable of unattended sampling and was operated with a minimum time resolution of 2.5 min. Details of the fluorimeter design and examples of data processing are provided, and results from a chamber study of side-stream cigarette smoke and ambient monitoring campaign in Guangzhou, China are presented. Primary cigarette smoke was shown to have both short-lived (t1/2 = 27 min) and long-lived (t1/2 = indefinite) PM-bound reactive oxygen species (ROS) components which had previously only been observed in secondary organic aerosol (SOA).

The Sydney Particle Study involved the comprehensive measurement of meteorology, particles and gases at a location in western Sydney during February–March 2011 and April–May 2012. The aim of this study was to increase scientific understanding of particle formation and transformations in the Sydney airshed. In this paper we describe the methods used to collect and analyse particle and gaseous samples, as well as the methods employed for the continuous measurement of particle concentrations, particle microphysical properties, and gaseous concentrations. This paper also provides a description of the data collected and is a metadata record for the data sets published in Keywood et al. (2016a, https://doi.org/10.4225/08/57903B83D6A5D) and Keywood et al. (2016b, https://doi.org/10.4225/08/5791B5528BD63).

Particle emission characteristics and engine performance were investigated from an auxiliary, heavy duty, six-cylinder, turbocharged and after-cooled diesel engine with a common rail injection system using spiked fuels with different combinations of sulphur (S) and vanadium (V) spiking. The effect of fuel S content on both particle number (PN) and mass (PM) was clearly observed in this study. Higher PN and PM were observed for fuels with higher S contents at all engine load conditions. This study also found a correlation between fuel S content and nucleation mode particle number concentration which have more harmful impact on human health than larger particles. The highest PN and PM were observed at partial load conditions. In addition, S in fuel resulted in higher viscosity of spiked fuels, which led to lower engine blow-by. Fuel V content was observed in this study, evidencing that it had no clear effect on engine performance and emissions. Increased engine load also resulted in higher engine blow-by. The lower peak of in-cylinder pressure observed at both pre-mixed and diffusion combustion phases with the spiked fuels may be associated with the lower energy content in the fuel blends compared to diesel fuel.

Internally and externally mixed aerosols present significant challenges in assessing the hygroscopicity of each aerosol component. This study presents a new sampling technique which uses differences in volatility to separate mixtures and directly examine their respective composition and hygroscopic contribution. A shared thermodenuder and unheated bypass line are continuously cycled between an aerosol mass spectrometer and a volatility and hygroscopicity tandem differential mobility analyser, allowing real-time comparative analysis of heated and unheated aerosol properties. Measurements have been taken of both chamber-generated secondary organic aerosol and coastal marine aerosol at Cape Grim, Australia, to investigate system performance under diverse conditions. Despite rapidly changing aerosol properties and the need to restrict analysis to a narrow size-range, the former experiment separated the hygroscopic influences of ammonium sulfate and two distinct organic components with similar oxygen to carbon ratios but different volatilities. Analysis of the marine aerosol revealed an external mixture of non-sea salt sulfates and sea spray aerosol, both of which likely shared similar volatile fractions composed of sulfuric acid and a non-hygroscopic organic component.

Rationale: Exposure to diesel emissions (DE) has been associated with the development of lung cancer and increased COPD mortality in at-risk populations. The aim of this study was to investigate disease-specific changes in the expression of intracellular signalling genes in primary human bronchial epithelial cells (pHBECs) in response to diesel emission exposure using the Nanostring nCounter Intracellular Signalling RNA panel. Methods: 14 pHBEC lines (see Table 1) were exposed to DE for 30 minutes through the Cultex RFS. RNA was extracted using QIAGEN AllPrep kits. Gene expression changes of 192 intracellular signalling genes were assessed using the Nanostring nCounter Intracellular Signalling RNA panel. Quality control analysis and data analysis was performed using the nSolver Analysis Software v3.0. Results: DE exposure altered expression patterns of intracellular signalling genes in disease cohorts. Five genes had significantly altered expression levels after exposure to diesel emissions, when compared to FA. Conclusions: pHBECs may produce different intracellular signalling responses after diesel emission exposure, depending on the disease cohort. pHBECs increase the expression of immune regulating, inflammatory and anti-inflammatory genes after diesel emission exposure.

The SAFIRED (Savannah Fires in the Early Dry Season) campaign took place from 29 May until 30 June 2014 at the Australian Tropical Atmospheric Research Station (ATARS) in the Northern Territory, Australia. The purpose of this campaign was to investigate emissions from fires in the early dry season in northern Australia. Measurements were made of biomass burning aerosols, volatile organic compounds, polycyclic aromatic carbons, greenhouse gases, radon, speciated atmospheric mercury and trace metals. Aspects of the biomass burning aerosol emissions investigated included; emission factors of various species, physical and chemical aerosol properties, aerosol aging, micronutrient supply to the ocean, nucleation, and aerosol water uptake. Over the course of the month-long campaign, biomass burning signals were prevalent and emissions from several large single burning events were observed at ATARS. Biomass burning emissions dominated the gas and aerosol concentrations in this region. Dry season fires are extremely frequent and widespread across the northern region of Australia, which suggests that the measured aerosol and gaseous emissions at ATARS are likely representative of signals across the entire region of north Australia. Air mass forward trajectories show that these biomass burning emissions are carried north-west over the Timor Sea and could influence the atmosphere over Indonesia and the tropical atmosphere over the Indian Ocean. Here we present characteristics of the biomass burning observed at the sampling site and provide an overview of the more specific outcomes of the SAFIRED campaign.

There is a lack of knowledge of how biomass burning aerosols in the tropics age, including those in the fire-prone Northern Territory in Australia. This paper reports chemical characterization of fresh and aged aerosols monitored during the 1-month-long SAFIRED (Savannah Fires in the Early Dry Season) field study, with an emphasis on the chemical signature and aging of organic aerosols. The campaign took place in June 2014 during the early dry season when the surface measurement site, the Australian Tropical Atmospheric Research Station(ATARS), located in the Northern Territory, was heavily influenced by thousands of wild and prescribed bushfires. ATARS was equipped with a wide suite of instrumentation for gaseous and aerosol characterization. A compact time-of-flight aerosol mass spectrometer was deployed to monitor aerosol chemical composition. Approximately 90% of submicron non-refractory mass was composed of organic material. Ozone enhancement in biomass burning plumes indicated increased air mass photochemistry. The diversity in biomass burning emissions was illustrated through variability in chemical signature (e.g. wide range in f44, from 0.06 to 0.18) for five intense fire events. The background particulate loading was characterized using positive matrix factorization (PMF). A PMF-resolved BBOA (biomass burning organic aerosol) factor comprised 24% of the submicron non-refractory organic aerosol mass, confirming the significance of fire sources. A dominant PMF factor, OOA (oxygenated organic aerosol), made up 47% of the sampled aerosol, illustrating the importance of aerosol aging in the Northern Territory. Biogenic isoprene-derived organic aerosol factor was the third significant fraction of the background aerosol (28 %).

Biomass burning (BB) is a significant air pollution source, with global, regional and local impacts on air quality, public health and climate. Worldwide an extensive range of studies has been conducted on almost all the aspects of BB, including its specific types, on quantification of emissions and on assessing its various impacts. China is one of the countries where the significance of BB has been recognized, and a lot of research efforts devoted to investigate it, however, so far no systematic reviews were conducted to synthesize the information which has been emerging. Therefore the aim of this work was to comprehensively review most of the studies published on this topic in China, including literature concerning field measurements, laboratory studies and the impacts of BB indoors and outdoors in China. In addition, this review provides insights into the role of wildfire and anthropogenic BB on air quality and health globally. Further, we attempted to provide a basis for formulation of policies and regulations by policy makers in China.

The emission factors (EFs) for a broad range of semivolatile organic chemicals (SVOCs) from subtropical eucalypt forest and tropical savannah fires were determined for the first time from in-situ investigations. Significantly higher (t test, P < 0.01) EFs (µg kg-1 dry fuel, gas + particle-associated) for polycyclic aromatic hydrocarbons (∑13 PAHs) were determined from the subtropical forest fire (7,000 ± 170) compared to the tropical savannah fires (1,600 ± 110), due to the approximately 60 fold higher EFs for 3-ring PAHs from the former. EF data for many PAHs from the eucalypt forest fire were comparable with those previously reported from pine and fir forest combustion events. EFs for other SVOCs including polychlorinated biphenyl (PCB), polychlorinated naphthalene (PCN), polybrominated diphenyl ether (PBDE) congeners as well as some pesticides (e.g. permethrin) were determined from the subtropical eucalypt forest fire. The highest concentrations of total suspended particles, PAHs, PCBs, PCNs and PBDEs were typically observed in the flaming phase of combustion. However concentrations of levoglucosan and some pesticides such as permethrin peaked during the smoldering phase. Along a transect (10 – 150 – 350m) from the forest fire, concentration decrease for PCBs during flaming was faster compared to PAHs while levoglucosan concentrations increased.