The number of global deaths caused by fossil-fuel related air pollution could be much larger than originally thought, with new research finding that as many as one-in-five deaths globally could be attributed to the use of coal, gas and oil.
The analysis, published in the journal Environmental Research, and led by researchers from Harvard University, the University of Birmingham, the University of Leicester and University College London, found that global deaths attributable to fossil fuel pollution could have been as high as 8.7 million in 2018 – double previous estimates.
The figure would suggest that fossil fuel related air pollution could be responsible for a total of one-in-five deaths globally, and almost half the reported deaths in some regions of Asia.
The study applied new techniques for measuring the level of pollution caused by the use of fossil fuels, including particulate matter. Such particulate pollution can be caused by dust and bushfires, in addition to fossil fuel combustion, and earlier measurement techniques were not able to differentiate the sources.
The research team used a new global 3-D model of atmospheric chemistry, called GEOS-Chem, to model the health impacts of particular sources of particulate matter – finding that fossil fuels were more detrimental to human health.
The researchers found that regions with the highest levels of fossil fuel caused air pollution, including Eastern North America, Europe, and South-East Asia had the highest rates of mortality.
The most recent Global Burden of Disease Study, generally accepted as the most comprehensive assessment of global causes of mortality, estimated that air pollution was responsible for 4.2 million annual deaths. The new Harvard study suggests this figure could be a substantial underestimate.
Eastern Asia was found to be the most affected by fossil fuel air pollution, where it was responsible for as much as 43 per cent of all deaths, as smog and particulates heavily impacted major cities.
China and India, where air pollution has long been a major issue in some of the world’s largest cities, were estimated have suffered 62 per cent of fossil fuel related pollution deaths, with around 2.4 million deaths recorded in China and 2.5 million deaths recorded in India.
“Our study adds to the mounting evidence that air pollution from ongoing dependence on fossil fuels is detrimental to global health. We can’t in good conscience continue to rely on fossil fuels, when we know that there are such severe effects on health and viable, cleaner alternatives,” co-author and University College London associate professor Eloise Marais said.
The researchers said the new analysis further underpinned the need for global action to be taken to reduce the use of fossil fuels, and that a switch to clean energy sources would have benefits for both human health, as well as working to limit the impacts of global warming.
“Often, when we discuss the dangers of fossil fuel combustion, it’s in the context of CO2 and climate change and overlook the potential health impact of the pollutants co-emitted with greenhouse gases,” co-author, professor Joel Schwartz said.
“We hope that by quantifying the health consequences of fossil fuel combustion, we can send a clear message to policymakers and stakeholders of the benefits of a transition to alternative energy sources.”
The researchers were optimistic that the measures to control fossil fuel pollution could lead to dramatic reductions in related deaths.
“While emission rates are dynamic, increasing with industrial development or decreasing with successful air quality policies, China’s air quality changes from 2012 to 2018 are the most dramatic because population and air pollution there are both large,” Marais added.
“Similar cuts in other countries during that time period would not have had as large an impact on the global mortality number.”
The study estimated that around 6,000 deaths in the Australia and Oceania region were attributable to fossil fuel pollution – which was proportionally lower than regions like Eastern Asia, as pollution had a less direct impact on major population centres.
The analysis was undertaken by researchers from Harvard University, the University of Birmingham, the University of Leicester and University College London.