Heavy metal pollution levels and health risk assessment of dust storms in Jazmurian region, Iran

The Jazmurian basin in Iran is an area affected by climate change and desertification where aerosols and dust storms are common. The aim of this work was to determine the human and ecological risks from atmospheric particles during dust storms in different cities in the Jazmurian basin. For this purpose, the dust samples were collected from Jiroft, Roodbar Jonoob, Ghaleh Ganj, Kahnooj and Iranshahr cities, which are located around the Jazmurian playa in southeast of Iran. Satellite-based Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol products and the Aerosol Optical Depth (AOD) were used to detect aerosol loading in the atmosphere. Moreover, the trace element composition of the collected particles was determined and used to evaluate human and ecological impact assessment using US EPA human health risk assessment and ReCiPe 2016 endpoint hierarchist impact assessment method incorporated in the OpenLCA 1.10.3 software. The human health risk assessment of the particles revealed high non-carcinogenic risks for children from exposure to nickel and manganese and carcinogenic risks in both adults and children due to hexavalent chromium, arsenic and cobalt during dust storm events. Terrestrial ecotoxicity was found to have the largest ecological impact on ecosystems with copper, nickel and zinc exhibiting the largest contributions.

Kinetic model of PFAS removal by semi-batch foam fractionation and validation by experimental data for K-PFOS

Adsorptive bubble separation techniques such as foam fractionation have recently been applied for the extraction of per- and polyfluoroalkyl substances (PFAS) from waters at both laboratory and operational scales. However, few authors have developed mathematical models of their removal of PFAS. This study presents a theoretical framework for the kinetics of PFAS removal from fresh and monovalent saline waters by a semi-batch foam fractionation process, by the mechanisms of adsorption, entrainment and volatilization, as a function of pertinent parameters including PFAS air-water adsorption, bubble radius, electrolyte concentration and ionic strength, PFAS volatility, and flow and geometric parameters. The freshwater model is validated for the removal of potassium perfluorooctane sulfonate (K-PFOS) using published experimental data (Meng, P. et al., Chemosphere, 2018, 203, 263-270). The proposed models provide quantitative tools for process design and the optimization of individual PFAS removal by semi-batch adsorptive bubble separation techniques such as foam fractionation.

Lead poisoning of backyard chickens: Implications for urban gardening and food production

Increased interest in backyard food production has drawn attention to the risks associated with urban trace element contamination, in particular lead (Pb) that was used in abundance in Pb-based paints and gasoline. Here we examine the sources, pathways and risks associated with environmental Pb in urban gardens, domestic chickens and their eggs. A suite of other trace element concentrations (including As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn) are reported from the sampled matrices. Sixty-nine domestic chickens from 55 Sydney urban gardens were sampled along with potential sources (feed, soil, water), blood Pb concentrations and corresponding concentrations in eggs. Age of the sampled chickens and house age was also collected. Commercial eggs (n = 9) from free range farms were analysed for comparative purposes. Study outcomes were modelled using the large Australian VegeSafe garden soil database (>20,000 samples) to predict which areas of inner-city Sydney, Melbourne and Brisbane are likely to have soil Pb concentrations unsuitable for keeping backyard chickens. Soil Pb concentrations was a strong predictor of chicken blood and egg Pb (p=<0.00001). Almost 1 in 2 (n = 31/69) chickens had blood Pb levels >20 μg/dL, the level at which adverse effects may be observed. Older homes were correlated with higher chicken blood Pb (p = 0.00002) and egg Pb (p = 0.005), and younger chickens (<12 months old) had greater Pb concentrations, likely due to increased Pb uptake during early life development. Two key findings arose from the study data: (i) in order to retain chicken blood Pb below 20 μg/dL, soil Pb needs to be < 166 mg/kg; (ii) to retain egg Pb < 100 μg/kg (i.e. a food safety benchmark value), soil Pb needs to be < 117 mg/kg. These concentrations are significantly lower than the soil Pb guideline of 300 mg/kg for residential gardens. This research supports the conclusion that a large number of inner-city homes may not be suitable for keeping chickens and that further work regarding production and consumption of domestic food is warranted.

Temporal and spatial variations of air pollution across China from 2015 to 2018

This study investigated concentrations of PM_2.5, PM₁₀, SO₂, NO₂, CO and O₃, and air quality index (AQI) values across 368 cities in mainland China during 2015-2018. The study further examined relationships of air pollution status with local industrial capacities and vehicle possessions. Strong correlations were found between industrial capacities (coal, pig iron, crude steel and rolled steel) and air pollution levels. Although statistical and significant reductions of PM_2.5, PM₁₀, SO₂, NO₂, CO and AQI values were observed in response to various laws and regulations in industrial sectors, both particle and gaseous pollutants still had annual average concentrations above recommended limits. In order to further reduce air pollution, more efforts can be done to control traffic emissions caused by minicars and heavy trucks, which was revealed after investigating 16 vehicle types. This was also consistent with the apparent air quality improvement during the COVID-19 lockdown period in China in 2020, despite industrial operations being still active at full capacities.

Life cycle impact assessment of metal production industries in Australia

Metal production industries are associated with positive economic benefits, however their activities are significantly resource and energy intensive, contributing to emission of pollutants and greenhouse gases to the environment. The balance between the economic inputs and environmental footprint of the metal production industries determines their contribution to sustainability. This work provides environmental impact assessment of the production of aluminium, copper, gold, iron and steel, lead, nickel and zinc, and considers their contribution to the economy. The emissions of selected representative industries in Australia were sourced from public national emission inventories and used as input parameters in the openLCA software. ReCiPe midpoint and endpoint hierarchist impact assessment methods were used to investigate the environmental impacts of the selected industries. The results indicate that lead, followed by aluminium and nickel production had the largest environmental impacts. The work further revealed the specific emissions for better control for each industry taking into consideration their relative environmental and economic impacts. For instance, adoption of renewable energy sources would significantly decrease the greenhouse gas emissions and the associated environmental impacts of the copper, zinc, gold, and iron and steel production industries. Improvement of sustainability of the production of lead would require further control of trace metal emissions, while for aluminium and nickel production, improved control of emissions of particles and the acidic gases SO₂ and NO_x.

Comparative life cycle assessment of system solution scenarios for residual municipal solid waste management in NSW, Australia

Life cycle assessment (LCA) is a promising tool to evaluate the environmental impacts of different technologies for sustainable waste management. This study employs LCA to assess environmental impacts of alternative scenarios for residual municipal solid waste (MSW) management in New South Wales (NSW) based on current conditions and policies. Six different scenarios including a baseline scenario (landfilling) were applied for NSW waste management for energy production and their impacts on environment. The initial results showed that the scenario 3 that employed anaerobic digestion for food waste, incineration for combustible waste and plastic waste, and landfilling for non-combustible waste produced electricity of 625 kWh/t, which was maximum compared to the other scenarios. LCA results further suggested that among all scenarios, scenario 5 (similar to scenario 3 except combustible waste was treated through gasification and plastic waste was recycled) has the lowest level of environmental burdens in global warming, freshwater and marine ecotoxicity, and human non-carcinogenic toxicity. The sensitivity analysis for energy conversion rates (23-30%) for incineration and plastic recycling rate (66-91.3%) for MSW was further conducted and the results showed that energy conversion rate of 30% makes scenario 3 more valuable for electricity generation and less impactful for ecosystems damage category compared to scenario 5. On the other hand, plastic recycling rate of 91.3% has the lowest environmental burdens and by decreasing recycling rate to 66% the environmental impacts increase; however, it was noticed that reduction in recycling rate does not make any change in the order of scenarios. Overall, the study suggests that each waste type in NSW should be treated with a specific technology to achieve the highest resource recovery and lowest environmental impacts where energy conversion and plastic recycling rates have significant impacts.

NO2 levels as a contributing factor to COVID-19 deaths: The first empirical estimate of threshold values

This study represents the first empirical estimation of threshold values between nitrogen dioxide (NO₂) concentrations and COVID-19-related deaths in France. The concentration of NO₂ linked to COVID-19-related deaths in three major French cities were determined using Artificial Neural Networks experiments and a Causal Direction from Dependency (D2C) algorithm. The aim of the study was to evaluate the potential effects of NO₂ in spreading the epidemic. The underlying hypothesis is that NO₂, as a precursor to secondary particulate matter formation, can foster COVID-19 and make the respiratory system more susceptible to this infection. Three different neural networks for the cities of Paris, Lyon and Marseille were built in this work, followed by the application of an innovative tool of cutting the signal from the inputs to the selected target. The results show that the threshold levels of NO₂ connected to COVID-19 range between 15.8 μg/m³ for Lyon, 21.8 μg/m³ for Marseille and 22.9 μg/m³ for Paris, which were significantly lower than the average annual concentration limit of 40 μg/m³ imposed by Directive 2008/50/EC of the European Parliament.

Pyrolysis of heavy metal contaminated biomass pre-treated with ferric salts: Product characterisation and heavy metal deportment

The metal(loid)-enriched Avicennia marina biomass obtained from phytoremediation was impregnated with two ferric salts (FeCl₃ and Fe(NO₃)₃) prior to pyrolysis at 300-700 °C, aiming to study the influence on pyrolytic product properties and heavy metal(loid) deportment. Results showed that the impregnated ferric salts increased the fixed carbon content of biochars, hydrocarbon fractions in bio-oils, and the evolution of CO and H₂ in gases. Cd in biomass could be effectively removed from the biomass by FeCl₃ impregnation. During pyrolysis, the ferric salts enhanced the elemental recovery of As, Cr, Ni and Pb in the biochars and decreased their distribution in gases. Notably, the ferric salt pre-treatment inhibited the mobility and bio-availability of most elements in the biochars. This study indicated that ferric salt impregnation catalysed the pyrolysis process of metal(loid) contaminated biomass, enabled the operation temperature at 500-700 °C with minimal environmental risks, providing a safe and value-added way to the phytoremediation-pyrolysis scheme.

The relevance of particle size distribution and bioaccessibility on human health risk assessment for trace elements measured in indoor dust

Trace metal contaminants in indoor dust pose a significant potential exposure risk to people because of the time spent indoors and the readily ingested and inhaled fine-grained composition of indoor dusts. However, there is limited trace metal data available on the specific interaction of dust particle size fraction and their respective bioaccessibility/bioavailability and its consequent effect on health risk assessment. This study addresses this knowledge gap by examining bioaccessible and bioavailable trace element concentrations (As, Cr, Cu, Mn, Ni, Pb, Zn) in 152 discrete size fractions from 38 indoor vacuum samples from a larger dataset (n = 376) of indoor dust from Sydney, Australia. Arsenic, Cu, Ni, Pb and Zn were most concentrated in the 90-150 μm fraction with Cr and Mn being more concentrated in < 45 μm fraction. Dust particle size fractions < 45 μm, 45-90 μm, 90-150 μm and 150-250 μm were analysed for their individual gastric phase (G-alone) in vitro trace element bioaccessibilities. Lead exposure risk was estimated using the United States Environmental Protection Agency's Integrated Exposure Uptake Biokinetic (IEUBK) children's model. Mean Pb bioaccessibility was 59.6%, 42%, 62% and 62.2% for < 45 μm, 45-90 μm, 90-150 μm, and 150-250 μm, respectively. Mean Pb absolute bioavailability (ABA) was lower at 26.2%, 18.4%, 27.2% and 27.3% for size fractions < 45 μm, 45-90 μm, 90-150 μm, and 150-250 μm, respectively. The predicted blood Pb (PbB) levels for a hypothetical child aged 1 to 3 years for each of the dust particle size fractions was > 5 μg/dL. Lead concentrations measured in the selected dust samples show a potential for adverse health impacts on young children with the greatest risk being from indoor dust sized 90-150 μm.

Contamination identification, source apportionment and health risk assessment of trace elements at different fractions of atmospheric particles at iron and steelmaking areas in China

China has the largest share of global iron and steel production, which is considered to play a significant contribution to air pollution. This study aims to investigate trace element contamination at different fractions of particulate matter (PM) at industrial areas in China. Three PM fractions, PM2.1-9.0, PM1.1-2.1 and PM1.1, were collected from areas surrounding iron and steelmaking plants at Kunming, Wuhan, Nanjing and Ningbo in China. Multiple trace elements and their bioavailability, as well as Pb isotopic compositions, were analysed for identification of contaminants, health risk assessment and source apportionment. Results showed that PM particles in the sites near industrial areas were associated with a range of toxic trace elements, specifically As, Cr(VI), Cd and Mn, and posed significant health risks to humans. The isotopic Pb compositions identified that coal and high temperature metallurgical processes in the steelmaking process were the dominant contributors to local air pollution in these sites. In addition to iron and steelmaking activities, traffic emissions and remote pollution also played a contributing role in PM contamination, confirmed by the differences of Pb isotopic compositions at each PM fraction and statistical results from Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE) and Geometrical Analysis for Interactive Aid (GAIA). The results presented in this study provide a comprehensive understanding of PM emissions at iron and steelmaking areas, which helps to guide subsequent updates of air pollution control guidelines to efficiently minimise environmental footprint and ensure long term sustainability of the industries.

Interrelationship of microplastic pollution in sediments and oysters in a seaport environment of the eastern coast of Australia

Since the middle of the twentieth century, microplastics have emerged as a pollutant of concern. Sea ports are recipients of large amount of discharges through ballast water, ship traffic and other commercial activities, which may additionally add to the overall marine microplastic pollution. The aim of this study was to determine the interrelationship of microplastic pollution in the sediments and oysters at six major seaports (Port Jackson, Botany, Kembla, Newcastle, Yamba and Eden) of New South Wales (NSW). The results revealed the significant abundance of microplastic particles both in sediments and oysters in all the studied seaports which were estimated to be around 83-350 particles/kg dry weight in the sediments and 0.15-0.83 particles/g wet weight in the oysters. Although, the abundance of microplastics showed similar pattern in the sediments and oysters of the studied seaports, oysters had higher number of microplastics than sediments in all sea ports. Moreover, the results showed that the shapes, size and colours in the oysters did not necessarily match the main components in the sediments, although the polymer types matched well between each other. Black fibres between 0.1mm-0.5mm in size were the most abundant microplastics in oysters, whereas white spherules between 0.5mm-1mm in size were dominant in the sediments of NSW seaports. Moreover, the analysis of variance between microplastic abundance in sediment and oysters showed a non-significant positive linear relationship. Fourier Transform Infrared analysis further indicated that both sediments and oysters contained microplastics with two main polymers, polyethylene terephthalate and nylon, which suggests that the abundance of microplastics in the study ports was highly influenced by the port activities, mainly the intensive commercial fishing and fish processing activities along with intensive anthropogenic and industrial activities inside and surroundings the port environments.

Characterization of size resolved atmospheric particles in the vicinity of iron and steelmaking industries in China

China currently faces environmental challenges of lower air quality, partly as a result of industrial activities. The aim of this study was to investigate the role of iron and steelmaking facilities to regional air quality in four selected industry dominated urban centres in China. Nine different particle size ranges present in atmospheric particles collected from four sites in Kunming (KM), Wuhan (WH), Nanjing (NJ) and Ningbo (NB) were analysed and compared with particles collected at one background site at the Ningbo Nottingham University (UN) with very little industrial influence in China. Similar mass concentration levels of particulate matter PM_2.1 and PM_1.1 were found at the three sites near older iron and steelmaking plants (KM, WH and NJ). Significantly lower levels of PM_2.1 and PM_1.1 were collected at the fourth site (NB), which is near to a modern and coastal iron and steelmaking plant. The particles collected had the highest mass concentration in the aerodynamic diameter range of 3.3-9.0 μm for all sites, except for the background site (UN). Scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy, and inductively coupled plasma were used to determine the surface morphology and particle chemistry. Al, Ca, Fe, K, Mg, Na and Zn were found as the most abundant elements in all samples. The enrichment factors show that elements As, Cd, Cr, Cu, Pb and Zn were significantly enriched in particles, especially in fine particles, posing an adverse impact on human health. This study can be used to assist the development of particle monitoring programmes in the vicinity of industrial areas and also help to establish an elemental modality dataset on the exposure and risk assessments of atmospheric particles.

Application of national pollutant inventories for monitoring trends on dioxin emissions from stationary industrial sources in Australia, Canada and European Union

Industrial sources, including iron ore sintering, municipal waste incineration and non-ferrous metal processing have been prominent emitters of dioxins to the environment. With the expanding industrial sectors, many international conventions were established in order to reduce the emission of dioxins in the past two decades. The Stockholm convention, a global monitoring treaty, entered into force in 2004 with the aim to promote development of strategies to reduce or eliminate dioxin emissions. According to the convention, parties are required to develop national inventory databases to report emission levels and develop a national implementation plan (NIP) to reduce further dioxin emissions. In order to understand the trend of dioxin emissions since 1990s this study provides a comparative assessment of dioxin emissions from different industrial sources by deriving emission data from the national inventory databases of Australia, Canada and the 28 European countries (EU-28). According to the data collected, iron and steel production and electricity generation were the highest emitters of dioxins in 2017 for Europe, Canada and Australia, when compared to other stationary industrial sources. The change in the trend of dioxin emissions from the iron and steel industry and the public electricity sector was also assessed. The emission of dioxins during 1990–2017 from both iron and steel production and electricity generation revealed a relative decreasing trend, except for Spain and Italy who showed higher level of emissions from iron and steel production in 2017. Furthermore, comparing emission data for metal production revealed that the blast furnace process was the prominent emitter of dioxins comparing to electric arc furnace process. Further investigation was performed to compare the amount of dioxin emitted from three different fuel types, black coal, brown coal and natural gas, used for electricity generation in Australia. The study showed that dioxin emissions from brown coal were higher than black coal for the last two years, while power production from natural gas emits the lowest amounts of dioxins to the environment.

Proximate determinants of particulate matter (PM2.5) emission, mortality and life expectancy in Europe, Central Asia, Australia, Canada and the US

BACKGROUND

The growing concern with environmental related impacts on mortality and morbidity means that the conceptual framework of environment-health-economic policy nexus is salient in the global debate on air pollution.

OBJECTIVES

With time series data spanning 2000-2016, this study explored the proximate determinants of ambient air pollution, mortality, and life expectancy in North America, Europe & Central Asia, and East Asia & Pacific regions.

METHODS

The study applied historical data on urban population, total pollution, energy consumption, GDP per capita, life expectancy, mortality rate and industrial PM_2.5 emissions to develop six parsimonious models using the generalized least squares (GLS) random-effects model estimation with first-order autoregressive [AR(1)] disturbance across 54 countries.

RESULTS

An increase in income level by 1% declined mortality rate by 0.01% and increased longevity by ~0.02% (95% Confidence Interval [CI]) in the long-run. An increase in industrial PM_2.5 emissions per capita by 1% decreased life expectancy by 0.004% and mortality rate by 0.02% (95% CI). Intensification of energy consumption and its related services by 1% were found to increase industrial PM_2.5 emissions by 0.42-0.45% (95% CI). An inversed-U shaped curve between PM_2.5 emissions per capita and income levels was found at a turning point of US$ 48,061. The validity of an environmental Kuznets curve hypothesis between ambient air pollution and urbanization was confirmed, while a rapid increase in population had a significant positive impact on ambient air pollution.

CONCLUSION

Ambient air pollution contributes significantly in reducing life expectancy and increasing mortality. However, sustained economic development, along with energy efficiency, and sustainable urban settlement planning and management are potential options for reducing ambient air pollution while improving quality of life and environmental sustainability.

Environmental sustainability assessment using dynamic Autoregressive-Distributed Lag simulations-Nexus between greenhouse gas emissions, biomass energy, food and economic growth

Increasing population demand has triggered the enhancement of food production, energy consumption and economic development, however, its impact on climate change has become a global concern. This study applied a novel environmental sustainability assessment tool using dynamic Autoregressive-Distributed Lag (ARDL) simulations for model estimation of the relationships between greenhouse gas (GHG) emissions, energy, biomass, food and economic growth for Australia using data spanning from 1970 to 2017. The study found an inversed-U shaped relationship between energy consumption and income level, showing a decarbonized and services economy, hence, improved energy efficiency. While energy consumption increases emissions by 0.4 to 2.8%, biomass consumption supports Australia's transition to a decarbonized economy by reducing GHG emissions by 0.13% and shifts the demand for fossil fuel. Food and energy consumption underpin socio-economic development and vice versa. However, food waste from production and consumption increases ecological footprint, implying a lost opportunity to improve food security and reduce environmental pressure from agricultural production. There is no single path to achieving environmental sustainability, nonetheless, the integrated approach applied in this study reveals conceptual tools which are applicable for decision making.

Investigation of Phosphate Removal Capability of Blast Furnace Slag in Wastewater Treatment

Blast Furnace Slag (BFS) is a by-product of iron making with a potential to be used in different applications. In this research, BFS is used to investigate the phosphate removal ability in wastewater. BFS has the required concentrations of surface calcium to potentially precipitate phosphate from wastewater. Removal of phosphate from wastewater depends on variety of conditions, such as the size of BFS particles, adsorbent dose, contact time and pH. The conditions responsible for phosphate removal from wastewater with BFS were analysed and the phosphate removal capacity optimised according to the BFS chemical content. The results in this work demonstrated that the basicity (CaO/SiO₂) of BFS has a reverse effect on phosphate removal capacity. High basicity reduces the capability of BFS for removal of phosphate. BFS composition before and after phosphate removal was determined with Energy Dispersive Spectroscopy (EDS), Fourier Transfer Infrared Spectroscopy (FTIR) and UV-Vis spectrophotometry. The results revealed that the slag samples added varying concentrations of trace metals Al, Cd, Co and Hg into the treated water, which will need to be further conditioned by dilution with unpolluted water or other treatments before disposal or re-use.

Bio-oil upgrading with catalytic pyrolysis of biomass using Copper/zeolite-Nickel/zeolite and Copper-Nickel/zeolite catalysts

The bio-oil obtained from a general pyrolysis process contains a higher concentration of oxygenated compounds and the resultant physical and chemical properties make it an unsuitable drop-in fuel. The oxygenated compounds in the bio-oil can be converted into hydrocarbons or less oxygenated compounds with the application of catalysts. This study demonstrated the bio-oil upgrading with the application of catalysts, comparing the catalytic effect of combined mono-metallic catalysts (Cu/zeolite and Ni/zeolite) and sole bi-metallic catalyst (CuNi/zeolite) on the composition of bio-oil and pyrolytic gases. The results demonstrated that in comparison to the combined mono-metallic catalysts, the sole bi-metallic catalyst showed better deoxygenation for all the oxygenated compounds and favoured the production of aliphatic hydrocarbons, whereas the combination of mono-metallic catalysts generated higher proportion of aromatic hydrocarbons in the bio-oil. In both cases, the catalysts equally favoured decarboxylation and decarbonylation reactions, as CO₂/CO of approximately 1 was obtained during the pyrolysis process.

Effect of temperature on heavy metal(loid) deportment during pyrolysis of Avicennia marina biomass obtained from phytoremediation

Slow pyrolysis of heavy-metal(loid)-contaminated Avicennia marina biomass obtained from phytoremediation was conducted to investigate the deportment of 12 heavy metal(loid)s in pyrolysis products (biochar, bio-oil, gas) at temperatures from 300 to 800 °C. The results indicated that different heavy metal(loid)s showed diverse volatilities, while all elements tended to transform into volatile products with the increase of pyrolysis temperature. Cd was found highly volatile, while Fe and Cu were non-volatile elements. The leaching analysis of biochars showed that pyrolysis was effective in reducing the mobility and bioavailability of the heavy metal(loid)s in biochars. Moreover, the risk assessment of biochars showed that the biochars derived from polluted biomass can be used as a potential soil amendment. Considering the energy consumption and risk of contaminant emission, pyrolysis temperatures of 400 to 500 °C were considered to be the optimum option for pyrolysis of this biomass.

Economic, social and governance adaptation readiness for mitigation of climate change vulnerability: Evidence from 192 countries

Adaptation strategies have become critical in climate change mitigation and impact reduction, to safeguard population and the ecosystem from irreparable damage. While developed countries have integrated adaptation plans and policies into their developmental agenda, developing countries are facilitating or yet to initiate adaptation policies in their development. This study examines the nexus between climate change vulnerability and adaptation readiness in 192 UN countries using mapping and panel data models. The study reveals Africa as the most vulnerable continent to climate change with high sensitivity, high exposure, and low adaptive capacity. Developed countries, including Norway, Switzerland, Canada, Sweden, United Kingdom, Finland, France, Spain, and Germany, are less vulnerable to climate change due to strong economic, governance and social adaptation readiness. International commitment from developed countries to developing countries is essential to strengthen their resilience, economic readiness and adaptive capacity to climate-related events.

Assessment of trace elements pollution in sea ports of New South Wales (NSW), Australia using macrophytobenthic plant Ecklonia radiata as a bio-indicator

In this study seaweeds (Ecklonia radiata) from six major sea ports of NSW, Australia were used as a bioindicator to assess the distribution and levels of trace elements accumulation in the ports compared to the background ecosystem. Bioconcentration ratio (BCR), biota sediment accumulation factor (BSAF), enrichment factor, multivariate statistical analysis and hierarchical cluster analysis were used to identify trace elements contamination. The results illustrate BCRs of Al, Fe, Mn, Zn, Pb, Cu, As and Ba in E. radiata whereas the BASFs portray boron enrichment in all sea ports along with bioaccumulation of As in Port Jackson and Pb in Port Botany. However, trace elements variations between studied and background locations was found to be significant for Port Kembla and Newcastle. The principal component analysis result explained four principal groups with 76.25% cumulative variance. Cluster analysis was further performed to detect major groups of elements and sites to portray interconnection between the contaminants and the locations.

Assessment of trace elements pollution in the sea ports of New South Wales (NSW), Australia using oysters as bioindicators

In this study Sydney rock oysters (S. glomerata) from six major sea ports of NSW, Australia were used as bioindicators to assess the distribution and levels of trace element accumulation in the ports. Substantial enrichment of Cu, Pb and Zn in the oysters of the sea ports were detected when compared to their background samples and the US Environmental Protection Agency (USEPA) provisional tolerable intake standard. Enrichment of As, Al, Fe, Mn, Br, Sr were also found in the oysters at the port areas. The bioconcentration ratios of the trace elements illustrated significant Fe, Cu, Zn, As, Mn, Al, Pb and Cr accumulation in S. glomerate. The biota sediment accumulation factor suggested Cu, Mn and Zn accumulation at two of the ports (Port Yamba and Botany), indicating availability of these metals in the oysters as strong metal accumulators. In addition, integrated metal contamination illustrated notable Fe, Zn, Cu and Al contamination at port environment, whereas cluster analysis portrayed interconnection between the contaminants and the study sites.

A review on Environmental Kuznets Curve hypothesis using bibliometric and meta-analysis

The Environmental Kuznets Curve (EKC) hypothesis dates back in decades and is still topical presently due to its importance in environmental policy formulation. There are several systematic reviews of the EKC hypothesis using traditional review method. However, this review employs bibliometric and meta-analysis to track historical trends on the theme using the VOSviewer software and meta-analytic methods. The review translates the network analysis into visualized forms based on authors' contribution, the impact of the research by countries, citations count, and text corpus modeling using a network data extracted from Web of Science. The meta-analysis reveals that the collection of studies that validate the inversed-U shaped relationship has an average of US$8910 as the turning point of annual income level. Low income and middle-income countries are found below the thresholds of annual income level while high-income countries are above. Heterogeneity is confirmed among turning point in studies on EKC hypothesis due to differences in the period of study and econometric methods used in model estimation. The empirical findings reveal that most of the studies on EKC hypothesis are based on atmospheric indicators, while literature is sporadic and limited on EKC hypothesis which employs land indicators, oceans, seas, coasts and biodiversity indicators, and freshwater indicators.

Effect of foreign direct investments, economic development and energy consumption on greenhouse gas emissions in developing countries

In accordance with the Sustainable Development Goal 17 of improving global partnership for sustainable development, this study examined the effect of foreign direct investment inflows, economic development, and energy consumption on greenhouse gas emissions from 1982 to 2016 for the top five emitters of greenhouse gas emissions from fuel combustion in the developing countries, namely; China, India, Iran, Indonesia and South Africa. The study employed a panel data regression with Driscoll-Kraay standard errors, U test estimation approach and panel quantile regression with non-additive fixed-effects. The study found a strong positive effect of energy consumption on greenhouse gas emissions and confirmed the validity of the pollution haven hypothesis. The environmental Kuznets curve hypothesis is valid for China and Indonesia at a turning point of US$ 6014 and US$ 2999; second, a U-shape relationship is valid for India and South Africa at a turning point of US$ 1476 and US$ 7573. Foreign direct investment inflows with clean technological transfer and improvement in labour and environmental management practices will help developing countries to achieve the sustainable development goals. Mitigation of greenhouse gas emissions depends on enhanced energy efficiency, adoption of clean and modern energy technologies, such as renewable energy, nuclear, and the utilization of carbon capture and storage for fossil fuel and biomass energy generation processes.

Assessment of contribution of Australia's energy production to CO2 emissions and environmental degradation using statistical dynamic approach

Energy production remains the major emitter of atmospheric emissions, thus, in accordance with Australia's Emissions Projections by 2030, this study analyzed the impact of Australia's energy portfolio on environmental degradation and CO₂ emissions using locally compiled data on disaggregate energy production, energy imports and exports spanning from 1974 to 2013. This study employed the fully modified ordinary least squares, dynamic ordinary least squares, and canonical cointegrating regression estimators; statistically inspired modification of partial least squares regression analysis with a subsequent sustainability sensitivity analysis. The validity of the environmental Kuznets curve hypothesis proposes a paradigm shift from energy-intensive and carbon-intensive industries to less-energy-intensive and green energy industries and its related services, leading to a structural change in the economy. Thus, decoupling energy services provide better interpretation of the role of the energy sector portfolio in environmental degradation and CO₂ emissions assessment. The sensitivity analysis revealed that nonrenewable energy production above 10% and energy imports above 5% will dampen the goals for the 2030 emission reduction target. Increasing the share of renewable energy penetration in the energy portfolio decreases the level of CO₂ emissions, while increasing the share of non-renewable energy sources in the energy mix increases the level of atmospheric emissions, thus increasing climate change and their impacts.

River sediment quality assessment using sediment quality indices for the Sydney basin, Australia affected by coal and coal seam gas mining

Coal mining activities in the Sydney basin have been historically associated with significant environmental impacts. The region is facing more recent coal seam gas extraction activities and the synergetic environmental impacts of the new mining activities are still largely unknown. The aim of this study was to provide environmental assessment of river sediments comparing upstream to downstream areas relative to industrial-discharge sites associated with coal and coal-seam-gas extraction within the Sydney basin. Various contaminants were measured to determine the sediment quality according to the Australian and New Zealand Environment and Conservation Council (ANZECC) guidelines. Arsenic, nickel and zinc were the main sediment contaminants in downstream samples exceeding the ANZECC guidelines. Degree of contamination (C_d), geoaccumulation index (I_geo), enrichment factor (EF), pollution load index (PLI) and sediment environmental toxicity quotients' increment in downstream sediment were estimated for the studied areas. Toxicology indices of metals present in the sediments near industrial discharge sites were used as an additional tool to compare the level of environmental effects with their increment. The study revealed that the sediments from coal mining sites were highly affected by increased concentrations of manganese, zinc, cobalt, nickel and barium. The sediments associated with coal mining activities were found to be substantially more affected than the sediments near coal seam gas production sites, mainly attributed to the different wastewater discharge licencing requirements. The approach applied in this study can be used as an additional model to assess the contribution of industrial and mining activities on aquatic environments.

Comparison of pollution indices for the assessment of heavy metals in the sediments of seaports of NSW, Australia

Sediments samples from six seaports of NSW, Australia were analysed for the presence of metal contamination. Geoaccumulation index (Igeo), enrichment factor (EF), pollution load index (PLI), potential ecological risk (PER) and sediment pollution index (SPI) along with multivariate statistical analysis were used to identify the pollution pattern and possible sources of metals in the ports. The results demonstrate Cu, Pb and Zn pollution (Igeo > 5) at most sites and enrichment of As, Ni, Mn (EF > 3) and other metals. The PER recommends serious pollution at Port Kembla and Eden. By contrast, PLI and SPI demonstrate high contamination in all ports with exception of Port Botany and Yamba. PCA and cluster analysis detected major groups of elements in which three distinct clusters of pollutants and sites were apparent by dendrogram which portray simple and effective baseline scenarios for port activity-related quality assessment of surface sediments.

Water quality assessment of Australian ports using water quality evaluation indices

Australian ports serve diverse and extensive activities, such as shipping, tourism and fisheries, which may all impact the quality of port water. In this work water quality monitoring at different ports using a range of water quality evaluation indices was applied to assess the port water quality. Seawater samples at 30 stations in the year 2016–2017 from six ports in NSW, Australia, namely Port Jackson, Botany, Kembla, Newcastle, Yamba and Eden, were investigated to determine the physicochemical and biological variables that affect the port water quality. The large datasets obtained were designed to determine the Water Quality Index, Heavy metal Evaluation Index, Contamination Index and newly developed Environmental Water Quality Index. The study revealed medium water quality index and high and medium heavy metal evaluation index at three of the study ports and high contamination index in almost all study ports. Low level dissolved oxygen and higher level of total dissolved solids, turbidity, fecal coliforms, copper, iron, lead, zinc, manganese, cadmium and cobalt are mainly responsible for the poor water qualities of the port areas. Good water quality at the background samples indicated that various port activities are the likely cause for poor water quality inside the port area.

Impacts of iron and steelmaking facilities on soil quality

Iron and steel are highly important materials used in a wide range of products with important contribution to the economic development. The processes for making iron and steel are energy intensive and known to contribute to local pollution. Deposition of the metals may also have adverse impacts on soil quality, which requires detailed assessment. The aim of this study was to investigate the impacts of iron and steelmaking facilities on the local soil quality. Soil samples were collected in the vicinity of two steelmaking sites in Australia, one based on blast furnace steelmaking operation, while the second site was based on electric arc furnace steel recycling. The soil samples were compared to a background site where no industrial impact is expected. The soil collected near industrial facilities contained larger toxic metal contents, however this concentration for all priority metals was within the Australian National Environmental Protection Measure guidelines for the acceptable recreational soil quality. When compared to the international soil quality guidelines, some of the soils collected near the industrial sites, particularly near the blast furnace operated steelmaking, exceeded the arsenic, iron and manganese (according to United States Environmental Protection Agency guidelines) and chromium, copper and nickel concentrations (according to the Canadian guidelines). The work further provided a novel environmental assessment model taking into consideration the environmental and health impacts of each element. The environmental assessment revealed most significant contribution of manganese, followed by titanium, zinc, chromium and lead. Titanium was the second most important contributor to the soil quality, however this metal is currently not included in any of the international soil quality guidelines.

Environmental impact of coal mining and coal seam gas production on surface water quality in the Sydney basin, Australia

The extraction of coal and coal seam gas (CSG) will generate produced water that, if not adequately treated, will pollute surface and groundwater systems. In Australia, the discharge of produced water from coal mining and related activities is regulated by the state environment agency through a pollution licence. This licence sets the discharge limits for a range of analytes to protect the environment into which the produced water is discharged. This study reports on the impact of produced water from coal mine activities located within or discharging into high conservation environments, such as National Parks, in the outer region of Sydney, Australia. The water samples upstream and downstream from the discharge points from six mines were taken, and 110 parameters were tested. The results were assessed against a water quality index (WQI) which accounts for pH, turbidity, dissolved oxygen, biochemical oxygen demand, total dissolved solids, total phosphorus, nitrate nitrogen and E .coli. The water quality assessment based on the trace metal contents against various national maximum admissible concentration (MAC) and their corresponding environmental impacts was also included in the study which also established a base value of water quality for further study. The study revealed that impacted water downstream of the mine discharge points contained higher metal content than the upstream reference locations. In many cases, the downstream water was above the Australia and New Zealand Environment Conservation Council and international water quality guidelines for freshwater stream. The major outliers to the guidelines were aluminium (Al), iron (Fe), manganese (Mn), nickel (Ni) and zinc (Zn). The WQI of surface water at and downstream of the discharge point was lower when compared to upstream or reference conditions in the majority of cases. Toxicology indices of metals present in industrial discharges were used as an additional tool to assess water quality, and the newly proposed environmental water quality index (EWQI) lead to better trend in the impact of coal and coal seam gas mining activities on surface water quality when compared to the upstream reference water samples. Metal content limits were based on the impact points assigned by the Agency for Toxic Substances and Disease Registry, USA. For environmental and health impact assessment, the approach used in this study can be applied as a model to provide a basis to assess the anthropogenic contribution from the industrial and mining activities on the environment.

Food wastes derived adsorbents for carbon dioxide and benzene gas sorption

Food wastes are produced worldwide in large quantities that could have potential to produce higher value products, including industrial adsorbents. The present work attempts valorization of food waste by CO₂ activation and functionalization through nitric acid and melamine treatment. The prepared porous materials were subjected to gas phase adsorption of CO₂ and benzene gases. The resultant highly porous carbon materials with surface area range from 797 to 1025 m²/g were synthesized showing uptake capacities of 4.41, 4.07, 4.18 and 4.36 mmol/g of CO₂ and 345, 305, 242.5 and 380.7 mg/g of C₆H₆ respectively for PyF515, PyF520, PyF715 and PyF720 in the absence of doped carbon matrix. Differential thermogravimetric (DTG) analysis showed the thermostability of the precursors to validate selected initial pyrolysis temperatures (500 and 700 °C). C₆H₆ sorption lies mainly in the physisorption region for all adsorbents ensuring re-generation potential. PyF720 and PyF520 recorded the highest isosteric enthalpy of 64.4 kJ/mol and 48.7 kJ/mol respectively, despite the low degree of coverage of the latter. Thus, PyF515 and PyF720 demonstrated the potential for use as sustainable and cost effective adsorbents for benzene gas containment suitable for swing adsorption system.

Agronomic assessment of pyrolysed food waste digestate for sandy soil management

The digestate (DFW) of an industrial food waste treatment plant was pyrolysed for production of biochar for its direct application as bio-fertilizer or soil enhancer. Nutrient dynamics and agronomic viability of the pyrolysed food waste digestate (PyD) produced at different temperatures were evaluated using germination index (GI), water retention/availability and mineral sorption as indicators when applied on arid soil. The pyrolysis was found to enrich P, K and other micronutrients in the biochar at an average enrichment factor of 0.87. All PyD produced at different temperatures indicated significantly low phytotoxicity with GI range of 106-168% and an average water retention capacity of 40.2%. Differential thermogravimetric (DTG) thermographs delineated the stability of the food waste digestate pyrolysed at 500 °C (PyD500) against the degradation of the digestate food waste despite the latter poor nutrient sorption potential. Plant available water in soil is 40% when treated with 100 g of digestate per kg soil, whereas PyD500 treated soil indicated minimal effect on plant available water, even with high application rates. However, the positive effects of PyD on GI and the observed enrichment in plant macro and micronutrients suggest potential agronomic benefits for PyD use, in addition to the benefits from energy production from DFW during the pyrolysis process.

An Analysis of Citizen Science Based Research: Usage and Publication Patterns

The use of citizen science for scientific discovery relies on the acceptance of this method by the scientific community. Using the Web of Science and Scopus as the source of peer reviewed articles, an analysis of all published articles on “citizen science” confirmed its growth, and found that significant research on methodology and validation techniques preceded the rapid rise of the publications on research outcomes based on citizen science methods. Of considerable interest is the growing number of studies relying on the re-use of collected datasets from past citizen science research projects, which used data from either individual or multiple citizen science projects for new discoveries, such as for climate change research. The extent to which citizen science has been used in scientific discovery demonstrates its importance as a research approach. This broad analysis of peer reviewed papers on citizen science, that included not only citizen science projects, but the theory and methods developed to underpin the research, highlights the breadth and depth of the citizen science approach and encourages cross-fertilization between the different disciplines.

Mass and elemental distributions of atmospheric particles nearby blast furnace and electric arc furnace operated industrial areas in Australia

The improved understanding of mass and elemental distributions of industrial air particles is important due to their heterogeneous atmospheric behaviour and impact on human health and the environment. In this study, particles of different size ranges were collected from three sites in Australia located in the vicinity of iron and steelmaking industries and one urban background site with very little industrial influence. In order to determine the importance of the type of industrial activity on the urban atmospheric quality, the industrial sites selected in this study were in the close proximity to two blast furnace operated and one electric arc furnace based steelmaking sites. The chemical compositions of the collected air particles were analysed using the proton induced X-ray emission (PIXE) technique. This study revealed significantly higher metal concentrations in the atmospheric particles collected in the industrial sites, comparing to the background urban site, demonstrating local influence of the industrial activities to the air quality. The modality types of the particles were found to be variable between the mass and elements, and among elements in the urban and industrial areas indicating that the elemental modal distribution is as important as particle mass for particle pollution modelling. The highest elemental number distribution at all studied sites occurred with particle size of 0.1 μm. Iron was found as the main dominant metal at the industrial atmosphere in each particle size range. The industrial Fe fraction in the submicron and ultrafine size particles was estimated at up to 95% which may be released from high temperature industrial activities with the iron and steelmaking industries being one of the major contributors. Hence, these industrial elemental loadings can highly influence the atmospheric pollution at local urban and regional levels and are required to consider in the atmospheric modelling settings.

Properties of oil and char derived from slow pyrolysis of Tetraselmis chui

Pyrolysis of biomass is a means to industrially manufacture renewable oil and gas, in addition to biochar for soil amendment and long-term carbon fixation. In this work, oil and char derived from the slow pyrolysis of the unicellular marine diatom Tetraselmis chui are analysed using a variety of techniques. The pyrolytic oil fraction exhibits a wide variety of fatty acids, alkanes, alkenes, amides, aldehydes, terpenes, pyrrolidinines, phytol and phenols, with a high heating value (HHV) of 28 MJ/kg. The biochar produced has a HHV of 14.5 MJ/kg and reveals a number of properties that are potentially valuable from an agronomic point of view, including high cation exchange capacity (CEC), large concentration of N, and a low C:N ratio. The quantity of C in T. chui biochar that can be expected to stabilise in soil amounts to approximately 9%/wt of the original feedstock, leading to a potential net reduction in atmospheric CO(2).

Influence of pyrolysis temperature on production and nutrient properties of wastewater sludge biochar

The important challenge for effective management of wastewater sludge materials in an environmentally and economically acceptable way can be addressed through pyrolytic conversion of the sludge to biochar and agricultural applications of the biochar. The aim of this work is to investigate the influence of pyrolysis temperature on production of wastewater sludge biochar and evaluate the properties required for agronomic applications. Wastewater sludge collected from an urban wastewater treatment plant was pyrolysed in a laboratory scale reactor. It was found that by increasing the pyrolysis temperature (over the range from 300 °C to 700 °C) the yield of biochar decreased. Biochar produced at low temperature was acidic whereas at high temperature it was alkaline in nature. The concentration of nitrogen was found to decrease while micronutrients increased with increasing temperature. Concentrations of trace metals present in wastewater sludge varied with temperature and were found to primarily enriched in the biochar.

Agronomic properties of wastewater sludge biochar and bioavailability of metals in production of cherry tomato (Lycopersicon esculentum)

This work presents agronomic values of a biochar produced from wastewater sludge through pyrolysis at a temperature of 550 degrees C. In order to investigate and quantify effects of wastewater sludge biochar on soil quality, growth, yield and bioavailability of metals in cherry tomatoes, pot experiments were carried out in a temperature controlled environment and under four different treatments consisting of control soil, soil with biochar; soil with biochar and fertiliser, and soil with fertiliser only. The soil used was chromosol and the applied wastewater sludge biochar was 10tha(-1). The results showed that the application of biochar improves the production of cherry tomatoes by 64% above the control soil conditions. The ability of biochar to increase the yield was attributed to the combined effect of increased nutrient availability (P and N) and improved soil chemical conditions upon amendment. The yield of cherry tomato production was found to be at its maximum when biochar was applied in combination with the fertiliser. Application of biochar was also found to significantly increase the soil electrical conductivity as well as phosphorus and nitrogen contents. Bioavailability of metals present in the biochar was found to be below the Australian maximum permitted concentrations for food.

Thermal processing of paper sludge and characterisation of its pyrolysis products

Paper sludge is a waste product from the paper and pulp manufacturing industry that is generally disposed of in landfills. Pyrolysis of paper sludge can potentially provide an option for managing this waste by thermal conversion to higher calorific value fuels, bio-gas, bio-oils and charcoal. This work investigates the properties of paper sludge during pyrolysis and energy required to perform thermal conversion. The products of paper sludge pyrolysis were also investigated to determine their properties and potential energy value. The dominant volatile species of paper sludge pyrolysis at 10 degrees C/min were found to be CO and CO(2), contributing to almost 25% of the paper sludge dry weight loss at 500 degrees C. The hydrocarbons (CH(4), C(2)H(4), C(2)H(6)) and hydrogen contributed to only 1% of the total weight loss. The bio-oils collected at 500 degrees C were primarily comprised of organic acids with the major contribution being linoleic acid, 2,4-decadienal acid and oleic acid. The high acidic content indicates that in order to convert the paper sludge bio-oil to bio-diesel or petrochemicals, further upgrading would be necessary. The charcoal produced at 500 degrees C had a calorific value of 13.3MJ/kg.

Thermal conversion of elephant grass (Pennisetum purpureum Schum) to bio-gas, bio-oil and charcoal

Elephant grass is an abundant, fast growing plant with significant potential as a renewable energy source and for conversion to higher calorific value fuels. This work investigates thermal conversion of elephant grass to bio-gas, bio-oil and charcoal under two heating rates of 10 and 50 degrees C/min. The energy required to pyrolyse elephant grass was evaluated using computer aided thermal analysis technique, while composition of the resultant bio-gas and bio-oil products were monitored with gas chromatographic and mass spectroscopic techniques. At 500 degrees C, the bio-gas compounds consisted primarily of CO2 and CO with small amounts of methane and higher hydrocarbon compounds. The heat of combustion of the bio-gas compounds was estimated to be 3.7-7.4 times higher than the heat required to pyrolyse elephant grass under both heating rates, which confirms that the pyrolysis process can be self-maintained. Faster heating rate was found to increase the amount of liquid products by 10%, while charcoal yields remained almost the same at 30%. The bio-oil mainly consisted of organic acids, phthalate esters, benzene compounds and amides. The amount of organic acids and benzene compounds were significantly reduced at 50 degrees C/min, while the yields of phthalate esters and naphthalene compounds increased. The difference in bio-oil composition with increased heating rate is believed to be associated with the reduction of the secondary reactions of pyrolysis, which are more pronounced under lower heating rate.

Influence of control variables on mannequin temperature in a paediatric operating theatre

BACKGROUND

Core temperature drops in all children having general anaesthesia. Convection heating may be useful, but its effectiveness in the paediatric setting is not established. Additionally, its utility in many paediatric situations is limited by blanket design.

METHODS

Using a mannequin model in a sham operation, we assessed the likely safety and effectiveness of a draping technique in association with a 'Bair Hugger' and a heat dissipation unit (HDU). In Part 1 of the study, the influence of ambient temperature was assessed. In Part 2, a simulated laparotomy was set up and a more detailed assessment of air temperatures around the mannequin was made. In addition, the effect of a change in the HDU design was assessed.

RESULTS

Part 1: the technique achieved 'near-plateau' temperature within 5-10 min. A difference of 8 degrees C in ambient temperature (between 18 and 26 degrees C) translated only to a 2-3 degrees C difference under the drapes. Part 2: the technique produced sidestream cooler zones at the head and shoulders. Air temperature at these sites was 28-34 degrees C, whereas at other points (irrespective of their distance from the heat source), it was 37-40 degrees C. Warm air reached sufficient skin sites to anticipate adequate heat transfer in the clinical situation. Air temperature at 'skin' surface stayed below 40 degrees C over the 90-min study period.

CONCLUSIONS

A customized HDU used in association with a 'Bair Hugger' unit and a careful surgical draping technique provides stable, safe and consistent air temperatures around a mannequin. Net heat gain by a child's body should occur with this arrangement. Further evaluation in a clinical study is underway.