Pollution cuts more lives short worldwide than war, terrorism, malaria, HIV, tuberculosis, drugs or alcohol.
That's the takeaway of a report published Tuesday in The Lancet Planetary Health, which analyzed the combined health risks of air, water and toxic chemical pollution in 2019. The results show that pollution is responsible for around 9 million premature deaths each year, or one in six globally. That puts its toll on par with smoking.
"We haven't been yelling from the top of the streets, saying, 'Look at this!' loud enough,'" said Richard Fuller, the report's lead author and the founder and CEO of the nonprofit Pure Earth, which focuses on addressing pollution in low- and middle-income countries.
Fuller's report is one of two this week that have sounded the alarm about the insidious danger of pollution. The second study, published Monday, looked at the U.S. and calculated that 53,000 premature deaths could be prevented per year in the country if all energy-related emissions were eliminated.
Fuller's study found that more than 90 percent of pollution-related deaths occur in low- and middle-income countries. The countries with the highest pollution-related deaths in 2019 were India, China, Nigeria, Pakistan and Indonesia.
Air pollution — from sources like vehicles, power plants and crop burning — is the most dire threat, since it was responsible for more than 6.5 million deaths in 2019, more than any other form of pollution that year. Air pollution increases the risk of heart disease, respiratory infections, lung cancer, tuberculosis, chronic respiratory disease, diabetes, kidney disease and low birth weight, all of which can lead to premature death.
A changing mix of types of pollution
Pollution-related deaths have stayed flat worldwide since 2015, according to Fuller's research. A previous study of his showed that pollution was also responsible for 9 million premature deaths in 2015. But the dominant forms of pollution have changed over time.
His new report suggests that deaths from household air and water pollution have declined since 2000, while deaths from outdoor air pollution and toxic chemicals have risen more than 66 percent since then.
That's in part due to the growth of developing economies, a process that often leads to improvements in household sanitation while simultaneously increasing the use of industrial chemicals and fossil fuels, experts said.
"It's a compounding problem. When you have high populations and high pollution, you have more mortality because of that," said Richard Peltier, an associate professor of environmental health sciences at University of Massachusetts Amherst, who wasn't involved in either study.
Scientists have also identified increasing amounts of toxic chemicals in household items like spices, paint, children's toys and cosmetics. In 2019, lead and other chemicals were responsible for 1.8 million deaths globally — up from 900,000 in 2000, the report found.
Lead alone now kills more people worldwide than HIV, Fuller said. Other forms of chemical pollution may be severely underestimated, he added.
"We're not measuring mercury or pesticides or chromium or arsenic or asbestos," he said. "If we were to measure properly all of the different chemical exposures, it's probably as big as air pollution."
How to blunt pollution's fatal threat
Experts said it's generally difficult for people to protect themselves from pollution-related health hazards, especially in less developed countries.
"You can wear face masks when it's really polluted — if you have, say, a wildfire event in your community," Peltier said, "but that's not something that's sustainable or even attainable in many parts of the world."
In smoky conditions, N95 masks offer the best protection, according to a 2021 study.
People can also install air filters in their homes, Peltier said. But the best form of protection is probably to monitor outdoor air quality and stay inside when it's poor.
"When we see it's hazy, maybe we will defer that afternoon jog," Peltier said.
On a larger scale, experts said, countries need to devote more funding to controlling pollution.
"If you could spend $1 to fix the problem, I would spend that dollar on transitioning energy economies to finding cleaner resources, whether that's implementation of electric vehicles [or] retrofitting power plants to cleaner burning fuels," Peltier said.
The U.S. has already improved its air quality dramatically: Between 1990 and 2020, the country saw a 78 percent decline in the combined emissions of six common pollutants. But Monday's study underscored that there's more to be done.
If the U.S. eliminated emissions from road vehicles, for instance, that could prevent around 11,700 premature deaths, the study estimated. Eliminating emissions from the electricity sector could prevent another 9,300 deaths.
"We have the technologies available to get us to essentially an emissions-free electricity sector nationwide in the U.S.," said Nicholas Mailloux, the lead author of that study and a graduate student at the University of Wisconsin–Madison. "Some other sectors will be trickier, like aviation."
"Obviously, that doesn't happen overnight," Mailloux added. "There will be a decadeslong process of ratcheting down emissions on the scale that we show."
Even if U.S. pollution levels do drop further, the health benefits of that would likely not be felt evenly. Mailloux's study found that lowering emissions in the Southwest would mostly benefit the people who live in that area, whereas lowering emissions in Rocky Mountain states like New Mexico and Utah would have strong spillover effects in the Midwest, Southeast and parts of the South.
The more states and regions coordinate their efforts, Mailloux said, "the more benefit you get everywhere."