Study shows air pollution leading risk factor for death globally

Air pollution is becoming the second leading risk for death globally for adults and children, according to a State of Global Air (SoGA) report released on Wednesday.

The study, for the first time produced in cooperation with the United Nations Children's Fund (UNICEF) and released in collaboration with the Health Effects Institute (HEI), found that air pollution accounted for 8.1 million deaths globally in 2021.

It listed high blood pressure as the leading risk factor for the deaths of adults and malnutrition the leading risk factor for children globally.

"Beyond these deaths, many more millions of people are living with debilitating chronic diseases, putting tremendous strains on healthcare systems, economies and societies," the study said. It found that children under 5 years old are especially vulnerable, with health effects including premature birth, low birth weight, asthma and lung diseases.

It said that in 2021, exposure to air pollution was linked to more than 700,000 deaths of children under 5, making it the second leading risk factor for death globally for this age group.

Some 500,000 of these child deaths were linked mainly to household air pollution in Africa and Asia due to cooking indoors with polluting fuels.

The new SoGA report analyzed recently released data from the 2021 Global Burden of Disease study, showing the severe health impacts of pollutants like fine particulate matter outdoor, household air pollution, ozone and nitrogen dioxide.

The report includes data from more than 200 countries and territories, indicating that nearly every person on Earth breathes unhealthy levels of air pollution daily, with far-reaching health implications.

"More than 90 percent of these global air pollution deaths – 7.8 million people – are attributed to PM air pollution, including ambient PM and household air pollution," the report said. "These tiny particles, measuring less than 2.5 micrometers in diameter, are so small they remain in the lungs and can enter the bloodstream, affecting many organ systems and increasing the risks for noncommunicable diseases in adults like heart disease, stroke, diabetes, lung cancer and chronic obstructive pulmonary disease (COPD)."

According to the report, PM 2.5 has been found to be the most consistent and accurate predictor of poor health outcomes worldwide.

"We hope our State of Global Air report provides both the information and the inspiration for change," said HEI President Dr. Elena Craft. "Air pollution has enormous implications for health. We know that improving air quality and global public health is practical and achievable."

The HEI is an independent U.S.-based nonprofit research organization.