Air pollution in Kathmandu Valley has worsened in recent days, prompting health warnings and growing calls for urgent government action. Despite rising public concern, authorities have so far limited their response to issuing advisories urging people to stay indoors.
Kathmandu topped the list of the world’s most polluted cities on Thursday afternoon, with an Air Quality Index (AQI) of 341, according to Swiss firm IQAir. By Saturday at 4:53 PM, the AQI had slightly improved to 189—but the PM2.5 concentration remained over 29 times higher than the World Health Organization’s (WHO) recommended safe limit .
AQI levels above 300 are considered hazardous, with any reading above 100 posing health risks—especially to vulnerable groups like children, the elderly, pregnant women, and those with chronic illnesses.
PM2.5 refers to fine particulate matter of 2.5 microns or smaller in diameter, which can penetrate deep into the lungs and enter the bloodstream, impacting major organs. According to the WHO, exposure to PM2.5 increases the risk of cardiovascular and respiratory diseases, including stroke, lung cancer, and chronic obstructive pulmonary disease (COPD).
Crisis Deepens, Action Still Limited
Some environmentalists have urged the government to declare a public health emergency and launch a nationwide awareness campaign. So far, no such measures have been introduced.
Climatologist Dr. Dharma Raj Uprety, attributed the toxic air to a combination of rising temperatures, stagnant wind patterns, crop residue burning, and widespread forest fires.
Government data recorded 253 wildfires across 45 districts on Wednesday alone.
Doctors are advising people to limit outdoor activity, especially in the morning when pollution peaks. Cardiologist Dr. Ranjit Sharma warned that “patients with heart conditions should avoid morning walks,” while ophthalmologist Dr. Muna Kunwar reported a rise in eye infections and dryness due to the smog.
Long-Term Patterns, Weak Enforcement
An ICIMOD analysis earlier this week showed that high pollution has been the norm in the Valley in 2025: with inhabitants suffering 75/90 days of unhealthy air in the past three months.
“Experts at the centre attribute the spike to pre-monsoon forest fires across Nepal, especially in the west where many districts are in moderate to extreme drought,” read the ICIMOD’s statement on Thursday. “On April 3, the Government of Nepal’s Air Quality Monitoring dashboard recorded a 24-hourly AQI of 365 (Bhaktapur), 273 (Shankapark), 248(Ratnapark), 235 (Bhaisipati) and 235(Khumaltar).”
The World Air Quality Report 2024 , published by IQAir last month, ranked Nepal as the world’s seventh most polluted country, with an average PM2.5 concentration of 42.8 µg/m³, up slightly from 42.4 µg/m³ in 2023. This figure exceeds the World Health Organization’s (WHO) annual safety guideline of 5 µg/m³ by more than eightfold.
Although Kathmandu ranked 193rd among the world’s most polluted cities, its average PM2.5 level surpassed WHO’s safe limit by over 10 times during five months of 2024: January, February, March, April, and December.
Notably, the highest monthly pollution level was recorded in April 2024 at 86.9 µg/m³, while the lowest was 9.9 µg/m³ in August.
Despite such figures, enforcement remains weak. The 2019 Air Quality Management Work Plan classifies AQI levels above 300 as a disaster. However, officials from the Environment Department admit that violators continue to evade penalties, even after repeated warnings.
“We've had less winter rain for four consecutive years,” said Environment Department Director General Gyanraj Subedi. “The lack of green infrastructure is compounding the crisis.”
While Meteorologist Pratibha Manandhar forecast slight improvements in air quality, she warned that the winds necessary to disperse pollutants are still out of sight.
The government has warned that high pollution levels may persist until mid-June. In the meantime, health experts are calling for immediate, coordinated action to protect public health and reduce emissions.
(With inputs from RSS)
