Kathmandu air is ‘unhealthy’

Kathmandu’s air quality reached above AQI 150 on Friday, placing the federal capital valley among the world’s most polluted cities. The reading falls into the “Unhealthy” category, meaning that air pollution poses health risks to everyone, not just sensitive groups.

Long-term exposure to particulate matter, particularly PM2.5, remains a persistent health burden in Nepal. Research shows that air pollution is a leading risk factor for death and disability in the country, contributing to tens of thousands of premature deaths annually from respiratory and cardiovascular illnesses. On average, a Nepali’s life expectancy is reduced by more than four years due to prolonged exposure to polluted air.

Experts say Kathmandu’s winter pollution is driven by multiple, interlocking factors, including vehicular emissions, road dust and construction debris, smoke from brick kilns and small industries, open waste burning, and household fuel use, as well as transboundary pollution, particularly smoke from northern India.

The valley’s bowl-shaped topography and seasonal temperature inversions trap pollutants near the surface, exacerbating the impact.

Kathmandu is not alone. Urban centres such as Pokhara, Birgunj, Biratnagar and Bharatpur regularly record AQI levels above the healthy threshold, especially during the dry winter season. Lives in the plains’ urban centres get further complicated as weatherly fog mixed with smoke emissions (smog) covers the cities for weeks.

Public health authorities advise limiting outdoor activity, particularly for children, older adults, and those with pre-existing respiratory conditions.