Millions of people are living with poor air quality, placing their health and lives at risk

IQAir has published its sixth Annual World Air Quality Report, which reveals troubling details of worldwide pollution in 2023. The report is an annual air quality analysis that tracks worldwide exposure to harmful levels of PM2.5 pollution. The report ranks 134 countries, territories, and regions across 7,748 locations using data from over 30,000 air quality monitoring stations around the globe.

Causing an estimated one in every nine deaths worldwide, air pollution is the greatest environmental threat to human health. According to the World Health Organization (WHO), air pollution is responsible for an estimated seven million premature deaths worldwide every year.1

Exposure to PM2.5 air pollution leads to and exacerbates numerous health conditions, including but not limited to asthma, cancer, stroke, and lung disease.2 Additionally, exposure to elevated levels of fine particles can impair cognitive development in children, lead to mental health issues, and complicate existing illnesses including diabetes.

PM2.5 concentration, fine particulate aerosol particles measuring up to 2.5 microns in diameter, is the primary air quality indicator for the World Air Quality Report. Measured in micrograms per cubic meter (?g/m³), PM2.5 is one of six common pollutants monitored and regulated by environmental agencies worldwide due to the significant impacts to human health and the environment.

PM2.5 can originate from a variety of sources, each potentially resulting in distinct chemical compositions and physical characteristics. Common components of PM2.5 include sulfates, black carbon, nitrates, and ammonium. Anthropogenic sources of PM2.5 are predominantly linked to combustion engines, industrial processes, power generation, coal and wood burning, agricultural activities, and construction. Natural sources include dust storms, wildfires, and sandstorms.

The story in Europe

The data used to create this report was aggregated from the global distribution of more than 30,000 regulatory air quality monitoring stations and low-cost air quality sensors operated by research institutions, governmental bodies, universities and educational facilities, non-profit non-governmental organizations, private companies, and citizen scientists.

The 2022 World Air Quality Report included data from 7,323 locations in 131 countries, regions, and territories. In 2023, those numbers have grown to include 7,812 locations in 134 countries, regions, and territories.

In 2023, 7 percent (135) of the cities in the region achieved the WHO annual PM2.5 guideline of 5 ?g/m3, including every city in Iceland.

The United Kingdom had the highest number of cities in Europe to achieve the WHO annual PM2.5 guideline level, with 30 cities reporting annual averages less than 5 ?g/m3, followed by Finland with 27, and Sweden with 14.

Overall, there was a general trend of lower annual average PM2.5 levels for European cities in 2023. There was a substantial shift in the number of cities previously classified in the yellow (2 to 3 times the WHO annual PM2.5 guideline) and orange (3 to 5 times the WHO annual PM2.5 guideline) breakpoint ranges in 2022, shifting to the green range (1 to 2 times the WHO annual PM2.5 guideline) in 2023.

While 39 percent of European cities were classified in the green breakpoint in 2022, more than half (54 percent) of European cities fell within this range in 2023.

A worldwide problem

Coverage in Africa has expanded significantly in 2023 with seven new countries being added to the region. Coverage has also expanded across Latin America with four additional countries included in 2023.

The African nations of Chad and Sudan, as well as the West Asian country of Iran, are notably absent in 2023 due to a lack of publicly available monitoring data. In 2023, 10 out of the reporting 134 countries and regions succeeded in achieving the WHO annual PM2.5 guideline value of 5 µg/m3 . With only 9 percent of globally reporting cities achieving the WHO annual PM2.5 guideline, much more work remains to be done to combat air pollution. While PM2.5 poses direct health risks, its implications extend beyond human health to complex environmental processes impacted by the Earth’s climate.

Climate change, primarily driven by greenhouse gas emissions, plays a pivotal role in influencing concentrations of PM2.5 air pollutants, and fossil fuel emissions are simultaneously responsible for the majority of PM2.5 related deaths.3 Simultaneously addressing air pollution and climate change goals is feasible, offering opportunities for comprehensive environmental improvements.