An estimated 1 in 5 deaths every year can be attributed to fossil fuel pollution, a figure much higher than previously thought, according to research.
The study shows that more than 8 million people around the globe die each year as a result of breathing in air containing particles from burning fuels like coal, petrol and diesel, which aggravate respiratory conditions like asthma and can lead to lung cancer, coronary heart disease, strokes and early death.
The research, led by Harvard University in collaboration with UCL, the University of Birmingham and the University of Leicester has been published in the journal Environment Research.
Co-author and UCL Associate Professor Eloise Marais (UCL Geography) said: “Burning fossil fuels produces fine particles laden with toxins that are small enough to penetrate deep into the lungs. The risks of inhaling these particles, known as PM2.5, are well documented.
“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.”
Regions with the highest concentrations of fossil fuel-related air pollution, including Eastern North America, Europe, and South-East Asia, have the highest rates of mortality.
Until now, the Global Burden of Disease Study, which is the largest and most comprehensive study on the causes of global mortality, put the total number of deaths each year from all outdoor airborne particulate matter (including dust and smoke from wildfires and agricultural fires) at 4.2 million people.
This study, based on data representative of conditions in 2018, calculates that fossil fuel emissions alone account for 8.7 million people’s deaths.
Previous research relied on satellite and surface observations to estimate the average global annual concentrations of PM2.5 airborne particles. But satellite and surface observations cannot distinguish between particles from fossil fuel emissions and those from dust, wildfire smoke or other sources.
Loretta J. Mickley, Senior Research Fellow in Chemistry-Climate Interactions at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS), and co-author of the study, explains: “With satellite data, you’re seeing only pieces of the puzzle. It is challenging for satellites to distinguish between types of particles, and there can be gaps in the data.
To overcome this challenge, researchers turned to GEOS-Chem, a global 3-D model of atmospheric chemistry developed at SEAS. It has high spatial resolution, meaning researchers could divide the globe into a grid with boxes as small as 50 km x 60 km and look at pollution levels in each box individually.
Karn Vohra, a graduate student at University of Birmingham and first author of the study, who is advised by UCL’s Eloise Marais, explains further: “Rather than rely on averages spread across large regions, we wanted to map where the pollution is and where people live, so we could know more exactly what people are breathing.”
