Toxic haze blankets Kathmandu, world's most polluted capital

Times of Oman

12-04-2025

Kathmandu: Nepal's Kathmandu has been covered by a toxic haze of dust and smoke for multiple days, with the sun glowing an eerie red through the smog. The Himalayan nation is famous for its mountains, including Mount Everest, but its capital is located in a valley which hasn't seen significant rainfall in six months.
Widespread forest fires in the valley's vicinity — particularly in the southern and eastern regions — have sent air pollution levels spiking, along with vehicle emissions and stagnant air trapped by the city's unique topography.
"Kathmandu Valley is shaped like a bowl. When there is no rainfall, pollutants remain suspended in the air without settling, and there is little wind movement. As a result, pollution accumulates in the valley," Bidhya Banmali Pradhan, an air pollution specialist at International Center for Integrated Mountain Development (ICIMOD), told DW.
"Unlike the plains, it takes longer here for polluted air to clear," she said.
ICIMOD is a regional body whose members include Nepal, India, China, and Pakistan. Recent ICIMOD data shows rising carbon monoxide levels in Kathmandu's air, posing a serious risk to human health. Flights at Kathmandu's Tribhuvan International Airport have been repeatedly disrupted due to poor visibility.
Kathmandu has worst air quality in the world
The Nepalese capital is currently ranked as the world's most polluted city in the terms of air quality by the IQ Air, a Swiss-based platform aggregating information on air pollution from various sources including governments, companies, and NGOs.
Its Air Quality Index (AQI) considers pollution levels between 0 and 50 to be good, 51–100 moderate, 101–150 unhealthy for sensitive groups, 151–200 unhealthy, 201–300 very unhealthy, and anything above 301 is deemed hazardous.
Last Thursday, Kathmandu's average AQI reached 348, with some areas recording levels over 400. Since then, the city has consistently topped global pollution rankings with AQI levels above 200.
Pollution drifting from across the border
But Nepal's air pollution troubles stretch far beyond its capital. Many regions in Nepal's south and east have also become unhealthy, AQI data shows.
"The primary cause of the recent rise in air pollution is forest fires," Hasana Shrestha, an environmental inspector at the Department of Environment (DoE), told DW. "These fires are not limited to Nepal — they are also occurring in India and Southeast Asia, and the impact is reaching us."
Shrestha added that emissions from vehicles, industries, brick kilns, open waste burning, and dust from construction sites further worsen air quality.
Cities near Nepal — such as New Delhi, Kolkata, Dhaka, Lahore, and Yangon — have also regularly appeared among the world's most polluted.
"During November–December, pollution mainly comes from sources across the border, particularly crop burning in Indian states of Punjab and Haryana," air pollution expert Pradhan told DW.
"From March to May, most pollutants are domestic, with forest fires playing a major role. Dry conditions turn forests into tinderboxes, triggering widespread fires. This eases once the monsoon begins in June," she added.
Pradhan noted that current PM 2.5 levels — airborne particles small enough to enter air sacks in the lungs — have soared more than 200 micrograms per cubic meter, well above safe limits.
Health authorities urge vulnerable groups to take precautions
According to the State of Global Air report published last year, air pollution was directly linked to 125 deaths in Nepal in 2021, and contributed to a total of 48,500 fatalities. It remains a leading cause of serious health conditions such as stroke and heart disease.
Scrambling to respond to the current crisis, Nepal government has issued public warnings urging residents to stay indoors, and some schools have temporarily shut down. The authorities reported overcrowded hospitals, with patients suffering from eye irritation, respiratory problems, throat infections, and skin conditions.
"Vulnerable groups — including children, the elderly, pregnant women, and those with chronic illnesses — must take extra precautions," health ministry spokesperson Prakash Budhathoki, said.
Government says its efforts 'not enough' against forest fires
Nepal is also considering reinstating a two-day weekend to limit public exposure to pollution. Traditionally, the country observes only Saturdays as a public holiday. However, in May 2022, a two-day weekend — Saturday and Sunday — was temporarily introduced as an economic measure to curb fuel imports.
Speaking at a public event on Sunday, Minister for Forests and Environment Ain Bahadur Shahi Thakuri admitted that the government lacks advanced equipment and adequate personnel to effectively control forest fires.
"All state mechanisms are involved in fire management, but government efforts alone are not enough," he said. "Collaboration is crucial — from civil society to local communities and youth."
'We talk more than we act'
Meanwhile, the Broad Citizens' Movement NGO has called for immediate action to combat the crisis.
"It is shameful that the government needs to be reminded about air pollution," the group said, while calling for urgent measures including temporarily shutting down highly polluting factories and limiting car traffic.
Critics say the government often appears reactive rather than proactive.
"We talk more than we act," environmental inspector Shrestha told DW. "We need at least one lead authority to take real, coordinated action."
Multiple countries need to work together
Experts like Shrestha and Pradhan stress the need for both immediate and long-term strategies to curb the rising pollution, particularly for the Kathmandu Valley.
Shrestha proposed relocating brick kilns outside the valley, enforcing stricter vehicle emissions standards, regularly monitoring industries, and ensuring inter-agency coordination for tangible results.
In turn, Pradhan from the regional ICIMOD initiative pointed to the importance of international cooperation to tackle the problem.
"South Asian countries — including India, Bangladesh, and Pakistan — must adopt an integrated air pollution policy and enforce it strictly," Pradhan said.
"Having policies on paper is not enough," she added. "We need implementation — through incentives for cleaner practices, gradual replacement of polluting industries, and consistent monitoring."