Only 13 countries, territories and regions globally met the World Health Organization's guidelines for healthy air quality last year, according to a new report from Swiss technology company IQAir.
The company, which has worked with the United Nations Environmental Program, UN-Habitat and Greenpeace to combat air pollution, examined air data from more than 30,000 stations and sensors that monitor air quality from 7,323 cities across 131 countries, regions, and territories.
According to the report, Australia, Bermuda, Bonaire, Estonia, Finland, French Polynesia, Grenada, Guam, Iceland, New Caledonia, New Zealand, Puerto Rico, Sint Eustatius and Saba, and the U.S. Virgin Islands have all achieved the target air quality guidelines of PM2.5, or five micrograms per cubic meter or less.
PM2.5 is a fine particulate matter that is an air pollutant that can harm people's health when the levels are high, according to the New York State Department of Health.
When high, those particles can decrease visibility and make the air seem hazy, according to the NYS Department of Health.
"The size of particles is directly linked to their potential for causing health problems," the Environmental Protection Agency said. "Small particles less than ten micrometers in diameter pose the greatest problems, because they can get deep into your lungs, and some may even get into your bloodstream."
Last year, countries and territories in Africa and Central and South Asia had the highest yearly average of PM2.5 concentrations by population, according to IQAir.
Chad has the highest concentration of PM2.5, with 89.7 micrograms per cubic meter; followed by Iraq with 80.1; and Pakistan with 70.9, according to the report.
Bahrain, Bangladesh, Burkina Faso, Kuwait, India, Egypt and Tajikistan comprise the rest of the report's top 10 most polluted countries.
Despite growth in recent years, procuring air quality data in Africa continued to be an issue. Only 19 out of the continent's 54 countries had necessary data available, according to the report.
According to the report, 118 countries, or about 90%, did not meet the World Health Organization's recommended guidelines on air quality.
The WHO's air quality guidelines, implemented in 2021, were created for governments around the world to use as targets to reduce air pollution and ultimately improve people's health, the organization said.