KATHMANDU: Kathmandu Valley’s air pollution has decreased, with the Air Quality Index (AQI) dropping to 99 this afternoon.

Earlier this week, the AQI was 191 on Tuesday and fell to 114 on Wednesday.

The Department of Environment attributed the improvement to stronger winds dispersing pollutants.

According to the AQI data, Kathmandu, which was ranked the third most polluted city in the world on Tuesday, has now moved down to 18th place. Currently, Lahore in Pakistan leads with an AQI of 373, followed by Kolkata, India, at 186.

Department of Environment Director-General Gyanraj Subedi explained that pollution tends to rise during dry weather but decreases with rainfall and wind. “Rain helps settle dust and particles from the air, while wind disperses them, reducing pollution levels. We have advised relevant authorities to implement sustainable and eco-friendly development measures effectively,” he said.

Environmental expert Bhushan Tuladhar emphasized the need for timely preparedness, waste management, wildfire control, and strict enforcement of vehicle emission standards to maintain air quality.

Under the AQI scale, 0–50 is considered “Good” (green), 51–100 “Moderate” (yellow), 101–150 “Unhealthy for sensitive groups,” 151–200 “Unhealthy for all,” 201–300 “Very Unhealthy,” and above 300 “Hazardous,” Tuladhar noted, highlighting risks especially for people with respiratory or heart conditions.