Long-Term PM2.5 Exposure: The dangers of pollution aren't just limited to your lungs. According to a new study, it also affects the brain. Let's explain how and what impact it has.

Which disease is caused by pollution?

Long-Term Exposure to PM2.5 and Mental Health: While the central government's budget emphasized strengthening mental health infrastructure, a new national study paints a worrying picture. According to the research, long-term exposure to ultra-fine particles (PM2.5) present in polluted air is associated with an increased risk of depression and anxiety. This clearly demonstrates that environmental risks are exacerbating mental health problems in India.

This study, conducted by researchers from IIT Delhi in collaboration with AIIMS New Delhi, NIMHANS, and St. John's Medical College, has been published in the international journal iScience. The research analyzed data from 34,802 adults across 12 states, including Punjab, Uttar Pradesh, Rajasthan, and Assam.

What did the research reveal?

The research found that those exposed to long-term PM2.5 had an 8 percent higher risk of depression and a nearly 2 percent higher risk of anxiety. This analysis is based on clinically diagnosed cases from the National Mental Health Survey 2015-16. Since this is a cross-sectional study, it indicates correlation, not causation.

What do the experts say?

According to study author Dr. Anand Krishna, from the Department of Community Medicine at AIIMS, this distinction is important to understand. However, he also noted that when large populations are exposed to polluted air, even such "seemingly small" associations have serious implications. According to the report, the impact was most pronounced among those living in urban metropolitan areas, those aged 40 to 49, and those in lower income groups. Regional differences were also evident. Pollution-related depression was more pronounced in eastern India, while anxiety was more associated in western India.

What things were investigated?

The study wasn't limited to just total PM2.5 levels, but also examined its individual chemical components. It revealed that emissions from traffic, industry, and agriculture, such as sulfate, nitrate, and ammonium, were strongly linked to depression. Elemental carbon, a marker of diesel and fossil fuel combustion, was found to have the strongest association with anxiety.

The researchers say that identifying these components of pollution helps determine which emission sources should receive priority action. At a time when air quality continues to deteriorate in many parts of the country, the study included participants from Gujarat, Manipur, Madhya Pradesh, Chhattisgarh, West Bengal, Jharkhand, Tamil Nadu, and Kerala.