On. Oct. 23, 2025, Air pollution continues to exacerbate global health, including noncommunicable diseases and dementia, according to the sixth edition of the State of Global Air (SoGA) report released today. Air pollution remains the leading environmental risk factor for death around the world, contributing to 7.9 million deaths in 2023, with the largest health impacts seen in low- and middle-income countries where people have higher exposures and more limited access to healthcare and other services.

The report finds that of those, 6.8 million deaths (86%) were from noncommunicable diseases
(NCDs). Beyond this, NCDs also account for 161 million healthy years of life lost, resulting in high healthcare use, increased hospital admissions and the need for emergency medical care, loss of productivity and income, and mental health and other burdens for affected individuals, their caregivers, and families. The State of Global Air report was released by the Health Effects Institute (HEI), an independent US-based nonprofit research organization, in collaboration with the Institute for Health Metrics and Evaluation and the NCD Alliance. 

Noncommunicable diseases are diseases that typically last many years, slowly get worse over time, and are not transmissible from one person to another. These include heart disease, diabetes, cancer, stroke, and chronic obstructive pulmonary disease (COPD). Between 2000 and 2023, global NCD deaths due to air pollution increased from 5.99 million to 6.8 million, nearly a million more deaths, or 110 additional deaths every single day, an increase of 13%. Half of all chronic respiratory deaths are attributable to air pollution, as are one in four deaths from heart disease. 

This year, for the first time, the SoGA report includes information about the effects of air 
pollution on people living with dementia. In 2023, dementia related to air pollution resulted in 
more than 625,000 deaths around the world and nearly 12 million healthy years of life lost.

Since people with dementia require help with their daily care, a higher occurrence of this disease 
has rippling effects on economic productivity for families and caregivers, with an estimated 
global economic impact of over one trillion dollars a year. Women often bear the largest burden, 
being both more likely to provide care for people with dementia and more likely to develop 
dementia themselves.

Fine particle pollution (ambient PM2.5) is the largest driver of air pollution’s burden of disease 
worldwide. In 2023, 4.9 million deaths and 124 million healthy years of life lost were attributed 
to long-term exposures to ambient PM2.5 pollution. Primarily, PM2.5 comes from the burning of 
fossil fuels in vehicles, power plants, factories, and homes, as well as agricultural and industrial 
activities, waste burning, wildfires, and many other human and natural activities. 

Regions with the highest exposures to ambient PM2.5 pollution were South Asia; North Africa 
and the Middle East; and East, West, Central, and Southern Africa. In fact, the 20 countries with 
the highest exposure to ambient PM2.5 in 2023 are located in these three regions.

More than 36% of people around the world live in areas where PM2.5 levels do not meet even the 
least stringent interim target, set at 35 micrograms per cubic meter by the World Health 
Organization. Millions of people around the world experience severe air pollution episodes that 
cross borders, societies, and economies, bringing the threat of air pollution into stark focus. 

Household air pollution (HAP), which comes from the burning of solid fuels inside homes for 
cooking, heating, and other domestic tasks, was attributed to 2.8 million deaths, and an 
additional 470,000 deaths worldwide were attributed to ozone exposure. These health burdens 
vary widely around the globe, reflecting differences in exposures, underlying prevalence of 
disease, and other differences in population susceptibilities.