Air pollution remains the greatest external risk to human health as most countries fail to set or meet their standards for clean air.
While pollution slightly dipped due largely to a trend reversal in South Asia, more than three-quarters of countries worldwide have not set or aren’t meeting national pollution standards.
Though global pollution was slightly lower in 2022, its burden on life expectancy remains, according to new data from the Air Quality Life Index (AQLI).
The AQLI— developed by the University of Chicago’s Energy Policy Institute—is perhaps the most important pollution index that translates particulate air pollution and its impact on life expectancy.
If the world were to permanently reduce fine particulate pollution (PM2.5) to meet the World Health Organization’s (WHO) guideline, the average person would add 1.9 years onto their life expectancy—or a combined 14.9 billion life-years saved worldwide.
Air pollution impacts life expectancy, comparable to that of smoking, more than 4 times that of high alcohol use, more than 5 times that of transport injuries like car crashes, and more than 6 times that of HIV/AIDS.
Yet, the pollution challenge worldwide is vastly unequal. People living in the most polluted places on earth breathe air that is six times more polluted than the air breathed by those living in the least polluted places—and seeing their lives cut short by 2.7 years more because of it.
“While air pollution remains a global problem, its largest impacts are concentrated in a relatively small number of countries—cutting lives short several years in some places and even more than 6 years in some regions,” said Michael Greenstone, the Milton Friedman Distinguished Service Professor in Economics and one of the creators of the AQLI.
National standards are an important tool to set strong policies and improve air quality.
A third of the world’s population lives in regions that don’t meet the standards that their countries have set. If those countries did meet their own benchmarks, these 3 billion people would live an average of 1.2 years longer, according to the latest AQLI.
It also assesses that 37 out of 94 countries with standards aren’t meeting them, more than half of all countries and territories have not set a standard at all.
South Asia
Global pollution declined in 2022 due almost entirely to a trend reversal in South Asia. While pollution had been on the rise for more than a decade, it declined by 18 percent in one year. While it’s difficult to know for sure the reasons for this decline, meteorological causes—such as above normal rainfall—likely played a strong role and only time will tell whether policy changes are having an impact. Even with the decline, the region remains the most polluted in the world, accounting for 45 percent of total life years lost due to high pollution. The average person living in these countries would gain 3.5 years onto their lives if pollution were permanently reduced to meet the World Health Organization guideline.
Middle East and North Africa
Pollution has been on the rise in the Middle East and North Africa—2022 was no exception, with pollution increasing 13 percent. If this high level of pollution continues, residents are expected to lose about 1.3 years off their lives on average and 3 to 4 years in the most polluted areas such as Qatar—the world’s fourth most polluted country after the South Asian countries.
Central and West Africa
Air pollution is as much of a health threat in Sub-Saharan Africa as well-known killers in the region like HIV/AIDS, malaria and unsafe water, with pollution taking as much as 5 years off lives in the most polluted areas. The Democratic Republic of the Congo, Rwanda, Burundi, Cameroon and Equatorial Guinea are among the ten most polluted countries in the world. Yet, out of 27 countries in this region, only two have a national pollution standard. Those without a standard don’t even have the monitoring and open pollution data networks needed to help them set an appropriate standard.
China
Although the challenge of reducing air pollution across the world may seem daunting, China has had remarkable success, reducing pollution by 41 percent since 2013, the year before the country began a “war against pollution.” Due to these improvements, the average Chinese citizen can expect to live 2 years longer, provided the reductions are sustained. However, China still accounts for 20 percent of the world’s air pollution burden. The average person in China could see their life expectancy increase by 2.3 years more if the country met the WHO guideline for pollution.
Southeast Asia
Like South Asia, most of Southeast Asia experienced a decline in pollution in 2022, though pollution levels have remained dangerously high and largely unchanged for two decades. Almost all Southeast Asian residents breathe air deemed unsafe by the WHO guideline, reducing average life expectancy by 1.2 years.
Latin America
In many parts of Latin America, such as Columbia, air pollution’s toll on life expectancy is comparable to violence. While average air quality is at an unsafe but relatively low level across the region, the most polluted areas—located within Guatemala, Bolivia, and Peru—experience pollution similar to South Asia. In these regions, the average resident would gain up to 4 years of life expectancy if their air quality met the WHO guideline.
United States
In the United States, Americans are exposed to 67.2 percent less particulate pollution than they would have been in 1970—prior to the passage of the Clean Air Act—and they’re living 1.5 years longer because of it. Yet, 94 percent of the country still doesn’t meet the WHO’s guideline (5 µg/m3). This year, the EPA implemented a more stringent standard (10 µg/m3) for particulate pollution, gaining 1.9 million total life years if this standard is met. In 2022, 10 out of the top 20 most polluted counties were in California due to the impact of wildfires.
Europe
In Europe, residents are exposed to about 30.2 percent less pollution than they were in 1998, soon after the Air Quality Framework Directive started, gaining 5.6 months of life expectancy because of it. Yet, 96.8 percent of Europe still doesn’t meet the WHO’s guideline. In 2022, the EU proposed ratcheting down their standard of 25 µg/m³ to 10 µg/m³ by 2030. But 75 percent of the population in 12 out of 28 EU member countries don't meet this standard. The more polluted areas are in eastern Europe, where residents are living 4.8 months less than their western neighbors due to dirtier air. If all of the EU met the proposed standard, 56.4 million total life years would be gained.
