Researchers have reported that fossil fuel pollution caused more than eight million premature deaths in 2018, accounting for nearly 20 percent of adult mortality worldwide.
Going by their report in the journal, Environmental Research, half of that grim tally was split across China and India, with another million deaths equally distributed among Bangladesh, Indonesia, Japan and the United States.
This is coming as statistics previously said a ‘pandemic’ of air pollution shortens lives worldwide by nearly three years on average, and causes 8.8 million premature deaths annually.
Eliminating the toxic cocktail of molecules and lung-clogging particles cast off by burning oil, gas and coal would restore a full year of life expectancy, they reported in the journal Cardiovascular Research.
“Air pollution is a larger public health risk than tobacco smoking”, lead author, Jos Lelieveld, of the Max Planck Institute in Mainz, Germany told AFP.
“Much of it can be avoided by replacing fossil fuels with clean renewable energy.”
Compared to other causes of premature death, air pollution kills 19 times more people each year than malaria, nine times more than HIV/AIDS, and three times more than alcohol, the study found.
Coronary heart disease and stroke account for almost half of those deaths, with lung diseases and other non-communicable diseases such as diabetes and high blood pressure accounting for most of the rest.
Only six percent of mortality stemming from polluted air is due to lung cancer.
“Our results show there is air pollution pandemic”, said senior author, Thomas Munzel, of the Max Planck Institute’s departments of chemistry and cardiology.
“Both air pollution and smoking, are preventable, but over the past decades much less attention has been paid to air pollution than to smoking, especially among cardiologists.”
The worst-hit region is Asia, where average lifespan is cut 4.1 years in China, 3.9 years in India, and 3.8 years in Pakistan.
In some parts of these countries, toxic air takes an even steeper toll, other research has shown.
In India’s Uttar Pradesh—home to 200 million—small particle pollution by itself slashes life expectancy by 8.5 years, while in China’s Hebei Province (population 74 million) the shortfall is nearly six years, according to the Air Quality Life Index, developed by researchers at the Energy Policy Institute of Chicago.
African lives are also foreshortened by 3.1 years on average, with people in some nations—Chad, Sierra Leone, Central African Republic, Nigeria and Cote d’Ivoire—losing 4.5 to 7.3 years.
Among wealthier nations, the Soviet Union’s former satellite states have the deadliest pollution, especially in Bulgaria, Hungary and Romania.
“We show that about two-thirds of premature deaths are attributable to human-made pollution, mainly from fossil fuel use”, Munzel said.
“This goes up to 80 percent in high-income countries,” he added.
“5.5 million deaths worldwide a year are potentially avoidable.”
Unavoidable excess mortality stems from natural dust storms, such as in central Asia and northern Africa, along with forest fires, though both phenomena are being amplified by manmade climate change, according to climate scientists.
The least-impacted regions of the world are the Americas, western and northern Europe, and small island states.
The figure of 8.8 million premature deaths from outdoor air pollution each year is double estimates from World Health Organisation (WHO).
“The impact of air pollution on cardiovascular and other non-communicable diseases was significantly underestimated”, Lelieveld explained, echoing a conclusion from other recent research.
Air pollution causes damage to the blood vessels through greater oxidative stress, leading to increases in blood pressure, diabetes, stroke, heart attacks and heart failure.
The revised number for China is 2.8 million premature deaths each year, two-and-a-half times the WHO estimates.
The researchers said there are signs in India, China and other emerging economies that people are growing intolerant of life-shortening toxic air.
“The realisation that air pollution is a major health risk can contribute to the willingness to phase-out fossil fuels—with the co-benefit of reducing climate warming,” Lelieveld said.
To assess the impact of air pollution on life expectancy, the researchers applied data on exposure to micro-particles (PM2.5) and ozone for the year 2015 to models that simulate how chemical processes in the atmosphere interact with natural and manmade pollutants, and data from the Global Burden of Disease.
Indoor pollution—mainly from cookstoves fuelled by biomass or coal—is also a major killer, but was not considered here.
However, the toxic cocktail of tiny particles cast off by burning oil, gas and especially coal was responsible for a quarter or more of the mortality in half a dozen nations, all in Asia.
“We often discuss the dangers of fossil fuel combustion in the context of CO2 and climate change and overlook the potential health impacts”, co-author, Joel Schwartz, a professor of environmental epidemiology at the Harvard T.H. Chan School of Public Health, said in a statement.
The potential to avoid millions of premature deaths should be a powerful additional incentive for policymakers to drive down greenhouse gas emissions and hasten the global shift from brown to green energy, he said.
Worldwide, air pollution shortens lives by more than two years on average, earlier research has shown.
Worst-hit is Asia, where average lifespan is cut 4.1 years in China, 3.9 years in India, and 3.8 years in Pakistan. In some regions of these countries, life expectancy is reduced by twice as much.
In Europe, it is shortened by eight months on average.
The new study nearly doubles previous estimates of the number of people killed by fossil fuel pollution.
WHO says that air pollution—including indoors—kills seven million people per year, with 4.2 million of those deaths due to ambient, or outdoor, pollution.
The most recent Global Burden of Disease study—the most comprehensive catalogue of why people die—advances roughly the same numbers.
Both of these estimates relied on satellite data and surface observations to determine concentrations of the smallest—and most deadly—calibre of pollution, known as PM2.5.
But they cannot determine whether these microparticles come from burning fossil fuels or, say, dust and wildfire smoke, according to co-author Loretta Mickley, an expert in chemistry-climate interactions at Harvard.
“With satellite data, you’re seeing only pieces of the puzzle,” she said.
To get a more fine-grained picture of where particle pollution comes from and its health impacts, Mickley and colleagues used a 3-D model of atmospheric chemistry, known as GEOS-Chem, that divides Earth’s surface into 50-by-60-kilometre (30-by-36-mile) blocks.
A new risk assessment
“Rather than rely on averages spread across large regions, we wanted to map where the pollution is and where people live”, said lead author Karn Vohra, a graduate student at the University of Birmingham.
The next step was to plug in data on carbon emissions—from the power sector, industry, shipping, aviation and ground transport—along with NASA simulations of air circulation.
Once the researchers had PM2.5 concentrations for each box in the global grid, they still needed to determine the consequences for health.
Previous calculations of air pollution impacts—based on exposure to indoor second-hand smoke—seriously underestimate the danger, recent studies have found, so the researchers developed a new risk assessment model.
Compared with other causes of premature death, air pollution kills 19 times more people each year than malaria, nine times more than HIV/AIDS, and three times more than alcohol.
Coronary heart disease and stroke account for almost half of those deaths, with lung diseases and other non-communicable diseases such as diabetes and high blood pressure making up most of the rest.