Air pollution is harming brain health; India's disease burden is rising

                                 Air pollution is harming brain health; India's disease burden is rising

According to the State of Global Air 2025 report released by the Health Effects Institute (HI) and the Institute for Health Metrics and Evaluation (ISME), United States, two million lives were lost in India in 2023 due to air pollution-related diseases. This is a staggering increase from 1.4 million deaths in 2000, a 43 percent increase. Nearly nine out of 10 of these deaths were linked to non-communicable diseases (NCDs) such as heart disease, lung cancer, diabetes, and even dementia.

Globally, air pollution is responsible for eight million deaths annually - about one in eight deaths worldwide. More than half of these deaths (about 4.9 million) are caused by outdoor air pollution, 2.8 million by indoor air pollution and the rest by ozone pollution.

A major shock this time is the strong evidence of a link between air pollution and an increased risk of dementia, which caused 626,000 deaths globally and 40 million healthy years of life lost.

Rising burden of disease in India The death rate due to air pollution in India is now 10 times higher than in high-income countries with 186 deaths per 100,000 people, compared to 17 deaths per 100,000 in rich countries. States like Maharashtra, Uttar Pradesh, Rajasthan, Bihar and West Bengal have recorded the highest impact, with each state reporting more than 100,000 deaths in 2023.

The report highlights the increasing incidence of NCDs caused by air pollution. In 2023, 89 percent of deaths due to air pollution in India were due to NCDs, including heart and lung disease, lung cancer, diabetes and dementia.

According to the report, air pollution is responsible for seven out of 10 chronic obstructive pulmonary disease (COPD) deaths, one in three lung cancer deaths, more than one in four heart disease deaths and almost one in five diabetes deaths. More than two-thirds of all COPD deaths are due to exposure to air pollution. This points to a growing risk for India’s elderly population.

Globally, 95 percent of air pollution-related deaths among adults over 60 are due to NCDs. Between 2000 and 2023, global NCD deaths linked to air pollution increased by 13 percent, from 5.99 million to 6.8 million.

However, deaths due to household air pollution (due to the use of solid fuels for cooking) have been steadily declining in India. But deaths due to both ambient PM 2.5 and ozone have increased significantly. The magnitude of the risk is evident from the fact that 75 percent of the country’s population lives in areas where annual PM 2.5 exposure exceeds the WHO’s air quality interim target of 35 µg/m3.

New toxic front: Dementia A key highlight of this year’s report is the inclusion of dementia as a new indicator of the health harm of air pollution. In 2023, air pollution contributed to 626,000 dementia deaths worldwide and an estimated 40 million healthy years of life lost. Scientists have warned that long-term exposure to fine particles (PM 2.5) can damage brain tissue and accelerate cognitive decline.

In India, where life expectancy is increasing and the elderly care system is still underdeveloped, this finding is a significant concern. The country’s pollution-related dementia deaths, which were estimated to exceed 54,000 in 2024, represent a growing threat to families, healthcare systems and caregivers. The report says women are disproportionately affected, both as primary caregivers and as those at risk of developing dementia themselves.

Regional Highlights The burden of disease from air pollution is concentrated in low- and middle-income countries where rapid industrialization, industrial emissions and limited healthcare access exacerbate risks. South Asia remains the world’s worst-affected region, with India at the epicentre of the crisis.

In 2018, the UN High-Level Meeting on NCDs officially recognized air pollution as one of the five leading risk factors for chronic diseases, alongside tobacco use, unhealthy diet, physical inactivity and harmful alcohol consumption.

Subsequently, the World Health Assembly included air pollution in its global NCD framework, a turning point in government’s efforts to address the intersection between health and the environment. Yet, progress has been uneven. Most LMICs, including India, are unlikely to meet the UN’s Sustainable Development Goal 3.4, which calls for reducing NCD deaths by one third by 2030, without strong and sustained air pollution control efforts.

For India, this means integrating clean air strategies directly into national health and development planning. Integrated action needed This report highlights the dual opportunity of air pollution control, saving lives while supporting broader climate and health goals. Reducing exposure to PM2.5 and ozone not only reduces the risk of NCDs and dementia but also