Air quality in Kathmandu deteriorated sharply over the past 24 hours, placing the city second on global pollution rankings, according to IQAir. Kathmandu recorded an Air Quality Index (AQI) of 247, behind Lahore which registered an AQI of 381. AQI values above 200 are classified as very unhealthy and present serious health risks for the general population.
Fine particulate matter (PM2.5) is a major concern: these particles, smaller than 2.5 micrometres, can bypass the upper respiratory system, penetrate deep into the lungs and enter the bloodstream. PM2.5 stays suspended in the air, increasing the chance of inhalation and health harm.
Using the Environmental Protection Agency’s AQI scale, 151–200 is considered unhealthy for all, 201–300 very unhealthy with increased health risks for everyone, and readings above 300 are hazardous and can trigger severe health effects across the population.
Kathmandu, which covers about 413.7 square kilometres and housed nearly 2 million people in the 2022 census, has emerged as a pollution hotspot over the last decade. High population density increases exposure, while key pollution sources include industrial and household smoke, vehicle emissions, unregulated waste burning and vehicles that fail emission standards.
Nepal’s Ministry of Health estimates that air pollution causes around 42,000 deaths in the country each year. Of those deaths, roughly 19 percent are children under five and 27 percent are people over 70. The ministry also reports that air pollution has reduced average life expectancy in Nepal by about 4.1 percent. Overall air quality in the country remains far worse than World Health Organization guideline levels, creating a growing public health challenge.
Health experts warn that prolonged exposure to high pollution increases the risk of respiratory infections, exacerbates cardiovascular and lung conditions, and raises long-term health risks. Children, the elderly and people with pre-existing medical conditions are particularly vulnerable.
Authorities have urged residents to limit outdoor activities during severe pollution episodes, use masks that filter fine particles, and follow local advisories. Environmental groups and public health advocates are calling for stronger enforcement of emission standards, improved waste management, better urban planning and investment in sustainable transport to reduce pollution sources and protect public health.
