Over the last century or so, human life spans around the globe have almost doubled thanks to modern medicine, better nutrition and other improvements. Most people on Earth can expect to live to 70 and beyond. And while that jump is semi-miraculous, it’s not as great as it should be due to one particular cause: air pollution. Katy Daigle at ScienceNews reports on a new study suggesting that particulate matter in the air is robbing people around the globe of an average of one year of life—though the number ranges from just a few months in Western Europe and North America to 1.5 to 2 years in parts of Africa and Asia.
To investigate the impact of air pollution on mortality, the researchers pulled data from the Global Burden of Disease 2016 dataset, a comprehensive collection of all the diseases, injuries and other problems that kill people across the world each year. According to a press release, the team looked specifically at fine particulate matter, pollution particles smaller than 2.5 microns (PM2.5), about 30 times smaller than the width of a human hair, which can be inhaled deeply into the lungs. Exposure to these pollutants has been associated with increased incidence of stroke, heart attack and respiratory disease.
The research, led by Joshua Apte in the Cockrell School of Engineering at the University of Texas at Austin, examined PM2.5 exposure levels in 185 countries, then calculated the pollution's impact on life expectancy. The results appear in the journal Environmental Science & Technology Letters.
“A body count saying 90,000 Americans or 1.1 million Indians die per year from air pollution is large but faceless,” Apte says in the release. “Saying that, on average, a population lives a year less than they would have otherwise—that is something relatable.”
The impacts are quite different around the globe. In the United States, PM2.5 is shaving about four months off the average life. In Bangladesh and Egypt, where the amount of pollution is much higher, poor air is taking more than 1.8 years away from people. Overall, 42 countries saw their life expectancy drop by a year or more due to particulate matter.
But the study also has a more positive side. The researchers calculated how much life people would gain if countries were able to limit their exposure to 10 micrograms per cubic meter of PM2.5, the standard set by the World Health Organization. Meeting that goal would give the average Egyptian back 1.3 years of life, and improve outcomes for many people in the most polluted parts of the world. According to the release, in many countries the longevity boost from decreasing air pollution would be more than that from finding a cure for lung and breast cancer combined. “For much of Asia, if air pollution were removed as a risk for death, 60-year-olds would have a 15 percent to 20 percent higher chance of living to age 85 or older,” Apte says.
Like improving food and medicine, solutions for the air pollution problem are within reach. Somini Sengupta at The New York Times reports that nearly all common sources of PM2.5 are linked to fossil fuels and other greenhouse gas emitters. The upshot is that moving to cleaner power sources across the globe will improve health and lifespans. Not only is clean energy important for limiting climate change, it's also a major global health initiative. “For example, more efficient cars or cleaner electricity directly benefit both climate and health,” Apte tells Sengupta. “Indeed, the near- and long-term health benefits of cleaner and more efficient energy use are one of the best co-benefits of tackling climate change, as we will lead healthier and longer lives.”
But there are mixed signals about whether the nations of the world will make progress in reducing air pollution anytime soon. In the United States, Sengupta reports, the EPA recently rolled out a proposal to replace the Clean Power Plan, which pushed the energy sector toward cleaner energy, with a more fossil-fuel friendly agenda. Earlier this week Australia abandoned its Paris Agreement plan to reduce emissions 26 percent from the 2005 levels by 2030. And the one incredible piece of climate change news—that China had met its emissions goals 12 years earlier than projected—was countered by other research showing that emissions in the country have risen sharply in the last two years, a trend that could negate those gains. Which means it may be a while before we can all breathe easier.