We can use our superpower to help end fossil fuel pollution and rise to the challenge of climate change.

In this commentary, we argue that health professionals can play a pivotal role in accelerating the adoption of public policies that will help communities, nations, and the world end fossil fuel pollution and rise to the challenges of climate change. We briefly describe our previously published research showing that communicating about fossil fuel pollution and the health relevance of climate change has many benefits in building public support for climate action. Most importantly, we make the case that because health professionals, especially medical doctors and other clinicians, are highly trusted, we collectively have a unique opportunity to bring people together across the political continuum to have constructive dialogues about the intertwined problems of fossil fuel pollution and climate change and what to do about them - even in the current hyper-partisan environment.

The refinery of the future.

Fossil fuels-coal, oil and gas-supply most of the world's energy and also form the basis of many products essential for everyday life. Their use is the largest contributor to the carbon dioxide emissions that drive global climate change, prompting joint efforts to find renewable alternatives that might enable a carbon-neutral society by as early as 2050. There are clear paths for renewable electricity to replace fossil-fuel-based energy, but the transport fuels and chemicals produced in oil refineries will still be needed. We can attempt to close the carbon cycle associated with their use by electrifying refinery processes and by changing the raw materials that go into a refinery from fossils fuels to carbon dioxide for making hydrocarbon fuels and to agricultural and municipal waste for making chemicals and polymers. We argue that, with sufficient long-term commitment and support, the science and technology for such a completely fossil-free refinery, delivering the products required after 2050 (less fuels, more chemicals), could be developed. This future refinery will require substantially larger areas and greater mineral resources than is the case at present and critically depends on the capacity to generate large amounts of renewable energy for hydrogen production and carbon dioxide capture.

Infectious Diseases in a Changing Climate.

This JAMA Insights in the Climate Change and Health series discusses the importance of clinicians having awareness of changes in the geographic range, seasonality, and intensity of transmission of infectious diseases to help them diagnose, treat, and prevent these diseases.

Air pollution deaths attributable to fossil fuels: observational and modelling study.

OBJECTIVES: To estimate all cause and cause specific deaths that are attributable to fossil fuel related air pollution and to assess potential health benefits from policies that replace fossil fuels with clean, renewable energy sources. DESIGN: Observational and modelling study. METHODS: An updated atmospheric composition model, a newly developed relative risk model, and satellite based data were used to determine exposure to ambient air pollution, estimate all cause and disease specific mortality, and attribute them to emission categories. DATA SOURCES: Data from the global burden of disease 2019 study, observational fine particulate matter and population data from National Aeronautics and Space Administration (NASA) satellites, and atmospheric chemistry, aerosol, and relative risk modelling for 2019. RESULTS: Globally, all cause excess deaths due to fine particulate and ozone air pollution are estimated at 8.34 million (95% confidence interval 5.63 to 11.19) deaths per year. Most (52%) of the mortality burden is related to cardiometabolic conditions, particularly ischaemic heart disease (30%). Stroke and chronic obstructive pulmonary disease both account for 16% of mortality burden. About 20% of all cause mortality is undefined, with arterial hypertension and neurodegenerative diseases possibly implicated. An estimated 5.13 million (3.63 to 6.32) excess deaths per year globally are attributable to ambient air pollution from fossil fuel use and therefore could potentially be avoided by phasing out fossil fuels. This figure corresponds to 82% of the maximum number of air pollution deaths that could be averted by controlling all anthropogenic emissions. Smaller reductions, rather than a complete phase-out, indicate that the responses are not strongly non-linear. Reductions in emission related to fossil fuels at all levels of air pollution can decrease the number of attributable deaths substantially. Estimates of avoidable excess deaths are markedly higher in this study than most previous studies for these reasons: the new relative risk model has implications for high income (largely fossil fuel intensive) countries and for low and middle income countries where the use of fossil fuels is increasing; this study accounts for all cause mortality in addition to disease specific mortality; and the large reduction in air pollution from a fossil fuel phase-out can greatly reduce exposure. CONCLUSION: Phasing out fossil fuels is deemed to be an effective intervention to improve health and save lives as part the United Nations' goal of climate neutrality by 2050. Ambient air pollution would no longer be a leading, environmental health risk factor if the use of fossil fuels were superseded by equitable access to clean sources of renewable energy.

Association of cooking fuel use with risk of cancer and all-cause mortality among Chinese elderly people: a prospective cohort study.

When cooking with biomass and fossil fuels, their incomplete burning can lead to air pollution, which can trigger pernicious effects on people's health, especially among the elderly, who are more vulnerable to toxic and harmful environmental damage. This study explored the association between different cooking fuel types and the risk of cancer and all-cause mortality among seniors constructing Cox regression models. Data were obtained by linking waves of 6, 7, and 8 of the Chinese Longitudinal Healthy Longevity Survey, which included a total of 7269 participants who were 65 years old and over. Cooking fuels were categorized as either biomass, fossil, or clean fuels. And the effects of switching cooking fuels on death risk were also investigated using Cox regression models. The results indicate that, compared with the users of clean fuels, individuals using biomass or fossil fuels were at a greater death risk for cancer [HR (95% CI): biomass, 1.13 (1.05-1.20); fossil, 1.16 (1.06-1.25)] and all causes [HR (95% CI): biomass, 1.29 (1.16-1.42); fossil, 1.32 (1.22-1.50)]. Furthermore, compared with sustained users of biomass fuels, individuals converting from biomass to clean fuels significantly reduced death risk for cancer [HR (95% CI): 0.81 (0.72-0.95)] and all causes [HR (95% CI): 0.76 (0.64-0.93)]. Similarly, all-cause death risk [HR (95% CI): 0.77 (0.62-0.93)] was noticeably reduced among these participants converting from fossil to clean fuels than persistent users of fossil fuels. Subgroup analyses revealed that males had a greater cancer and all-cause death risk when exposed to unclean fuels. These findings can inform the development of policies and the implementation of measures related to cooking fuel use to promote the health of older people and reduce the burden of disease on society.

Cross-sectional study of household solid fuel use and renal function in older adults in China.

BACKGROUND: Emerging evidence links outdoor air pollution and declined renal function but the relationship between household air pollution and renal function is not well understood. METHODS: Using cross-sectional data from the multi-provincial INTERMAP-China Prospective Study, we collected blood samples and questionnaire information on stove use and socio-demographic factors. We calculated estimated glomerular filtration rate (eGFR) from serum creatinine to assess renal function. Participants with eGFR <60 mL/min per 1.73 m2 were defined as having chronic kidney disease (CKD) in this analysis. Generalized estimating equations were used to estimate the association of household fuel with renal function and prevalent CKD in models adjusting for confounders. RESULTS: Among the 646 enrolled adults (40-79y; 56% female), one-third exclusively used clean fuel (gas and electric) cookstoves and 11% of northern China participants (n = 49 of 434) used only clean fuel heaters, whereas the rest used solid fuel. In multivariable models, use of solid fuel cookstoves was associated with 0.17 ml/min/1.73 m2 (95% CI: -0.30, 0.64) higher eGFR and 19% (0.86, 1.64) higher prevalence of CKD than exclusive clean fuel use. Greater intensity of solid fuel use was associated with 0.25 ml/min/1.73 m2 (-0.71, 0.21) lower eGFR per 5 stove-use years, though the confidence intervals included the null, while greater current intensity of indoor solid fuel use was associated with 1.02 (1.00, 1.04) higher prevalent CKD per 100 stove-use days per year. Larger associations between current solid fuel use and intensity of use with lower eGFR and prevalent CKD were observed among participants in southern China, those with hypertension or diabetes (eGFR only), and females (CKD only), through these groups had small sample sizes and some confidence intervals included the null. CONCLUSION: We found inconsistent evidence associating household solid fuel use and renal function in this cross-sectional study of peri-urban Chinese adults.

Role of Defect Engineering and Surface Functionalization in the Design of Carbon Nanotube-Based Nitrogen Oxide Sensors.

Nitrogen oxides (NOx) are among the main atmospheric pollutants; therefore, it is important to monitor and detect their presence in the atmosphere. To this end, low-dimensional carbon structures have been widely used as NOx sensors for their outstanding properties. In particular, carbon nanotubes (CNTs) have been widely used as toxic-gas sensors owing to their high specific surface area and excellent mechanical properties. Although pristine CNTs have shown promising performance for NOx detection, several strategies have been developed such as surface functionalization and defect engineering to improve the NOx sensing of pristine CNT-based sensors. Through these strategies, the sensing properties of modified CNTs toward NOx gases have been substantially improved. Therefore, in this review, we have analyzed the defect engineering and surface functionalization strategies used in the last decade to modify the sensitivity and the selectivity of CNTs to NOx. First, the different types of surface functionalization and defect engineering were reviewed. Thereafter, we analyzed experimental, theoretical, and coupled experimental-theoretical studies on CNTs modified through surface functionalization and defect engineering to improve the sensitivity and selectivity to NOx. Finally, we presented the conclusions and the future directions of modified CNTs as NOx sensors.

Assessing a fossil fuels externality with a new neural networks and image optimisation algorithm: the case of atmospheric pollutants as confounders to COVID-19 lethality.

This paper demonstrates how the combustion of fossil fuels for transport purpose might cause health implications. Based on an original case study [i.e. the Hubei province in China, the epicentre of the coronavirus disease-2019 (COVID-19) pandemic], we collected data on atmospheric pollutants (PM2.5, PM10 and CO2) and economic growth (GDP), along with daily series on COVID-19 indicators (cases, resuscitations and deaths). Then, we adopted an innovative Machine Learning approach, applying a new image Neural Networks model to investigate the causal relationships among economic, atmospheric and COVID-19 indicators. Empirical findings emphasise that any change in economic activity is found to substantially affect the dynamic levels of PM2.5, PM10 and CO2 which, in turn, generates significant variations in the spread of the COVID-19 epidemic and its associated lethality. As a robustness check, the conduction of an optimisation algorithm further corroborates previous results.

Environmental sustainability assessment of biodiesel production from Jatropha curcas L. seeds oil in Pakistan.

According to IPCC Annual Report (AR-5), environmental impact assessment of any product prototype is recommended before its large-scale commercialization; however, no environmental profile analysis of any biodiesel prototype has been conducted in Pakistan. Therefore, objective of this study was to conduct a comprehensive life cycle assessment (LCA), water footprint and cumulative energy demand (CED) of biodiesel production from Jatropha curcas L. (JC) seeds oil in Pakistan. A cradle-to-gate LCA approach was applied for 400 liter (L) JC biodiesel produced in Pakistan. JC biodiesel production chain was divided into three stages i.e., 1). cultivation of JC crop 2). crude oil extraction from JC seeds and 3). crude oil conversion to biodiesel. Primary data for all the stages were acquired through questionnaire surveys, field visits and measurements in the field. Potential environmental impacts were calculated in SimaPro v.9.2 software using Eco-indicator 99 methodology. Results showed that crude oil extraction stage accounted for highest emissions (77%) to the overall environmental impact categories evaluated, followed by oil conversion stage (21%) and JC cultivation stage (02%), respectively. The three stages of JC biodiesel production chain are major contributor to ecotoxicity with a contribution of 57% to this impact category. Higher contribution to ecotoxicity was due to agrochemicals used in the JC cultivation. Similarly, fossil fuels impact category was responsible for 38% of overall environmental impacts. In addition, water footprint of JC biodiesel production chain was 2632.54 m3/reference unit. Cumulative energy required for 400L JC biodiesel production chain was 46745.70 MJ in Pakistan. Fossil diesel consumption, synthetic fertilizers use and purchased electricity were major hotspot sources to environmental burdens caused by JC biodiesel production in Pakistan. By performing sensitivity analysis at 20% reduction of the baseline values of fossil diesel used, synthetic fertilizers and purchased electricity, a marked decrease in environmental footprint was observed. It is highly recommended that use of renewable energy instead of fossil energy would provide environmental benefits such as lower greenhouse gases and other toxic emissions as compared to conventional petroleum fuels. It is also recommended that JC as a biofuel plant, has been reported to have many desired characteristics such as quick growth, easy cultivation, drought resistance, pest and insect resistance, and mainly great oil content in JC seeds (27-40%). Therefore, JC plant is highly recommended to Billion Tree Afforestation Project (BTAP) for plantation on wasteland because it has multipurpose benefits.