Air quality is once again worsening in the Kathmandu Valley and other places as farmers in India and Nepal burn stubble and other agricultural waste to prepare fields for new crops.

IQAir, a Swiss group that collects air quality data from around the world, ranked Nepal among the top six countries with the worst air quality on Thursday morning.

Lalitpur’s air quality index reached 238 at 12:45 pm on Thursday. According to the United States Environment Protection Agency’s air quality index, when air pollutants PM2.5 exceed 200μg/m3, air quality is considered very unhealthy, everyone may experience problems, with sensitive groups experiencing more severe effects.

Air quality monitoring stations placed at various places of the Kathmandu Valley, including Khumaltar, Ratnapark, Bhaktapur, and Shankapark, among others, also recorded deterioration in air quality.

Pakistan’s Lahore is ranked as the world’s most polluted city, with an air quality index reaching 1244 at 2 pm local time on Thursday.

Meteorologists attributed hazy conditions in the Kathmandu Valley on Thursday morning to pollution brought by southwesterly wind.

“A lack of rainfall and lack of strong winds for the last several days has worsened the air quality,” said Min Kumar Aryal, a meteorologist at the Meteorological Forecasting Division under the Department of Hydrology and Meteorology. “The pollution level could lessen starting Friday if wind conditions change.”

The Met Office said that no system is in place to cause rainfall in the next few days.

Environmentalists warn that the worst is yet to come, as open burning of waste materials and agriculture stubble has just started.

“Farmers both in India and Nepal are in a rush to clear fields for wheat cultivation,” said Bhupendra Das, an air quality and clean energy specialist. “They have been opting for easier methods like burning of stubble and open burning of waste, both of which are major contributors to worsening air quality.”

A past study shows that around three million tonnes of agricultural residue are burnt in the Tarai. Many other factors—emissions from brick kilns, factories, vehicular emissions, and construction activities among others—also contribute to the deteriorating air quality.

Doctors say poor air quality can have both short- and long-term impacts on public health. Bad air quality can cause pneumonia, bronchitis, conjunctivitis, skin allergies, stroke, and heart problems, among others, in the short term, and ulcers and cancer of the lungs and intestines, kidney disease and heart problems over the long term.

Experts say that the public is bearing the brunt of the authorities’ inaction in enforcing measures to improve air quality. They say that launching awareness drives against the hazards of open waste burning, and restrictions on unnecessary vehicular movement can help improve air quality.

“Some local units have begun enforcing a ban on open burning, purchased equipment to check vehicle emissions, and started monitoring air quality emissions from brick kilns,” said Bhusan Tuladhar, an environment expert. “A lot of work is needed to improve air quality during the dry season. Local units have taken steps, but the federal government has yet to implement effective measures to control the worsening air quality.”

Meanwhile, the Environment Department under the Kathmandu Metropolitan City said it has directed the metropolis to take immediate action against anyone burning waste.

“But what we should not forget is that there are several other local units within the Kathmandu Valley where open burning also occurs, and this causes air pollution not only in the immediate surroundings, but across the Valley,” said Sarita Rai, chief of the department. “All agencies concerned must shoulder responsibility to reduce emissions, especially those from open burning.”

The metropolis has also started cleaning dusty roads and pavements with water. Officials said that the metropolis’ water tankers are being used to wash pavements and dusty roads.

The city office has also requested the Department of Environment, which is part of the federal government, to encourage all local units across the country to restrict open burning strictly.

“We are aware of the worsening air quality in Kathmandu Valley and other places across the country,” said Deepak Gyawali, the department’s information officer. “We are currently organising an orientation programme for representatives from all metropolitan cities and provincial governments. We are trying to remind them of their responsibilities.”

Besides open burning, officials say polluted air from India and road dust are equally responsible for the deteriorating air quality, officials said. They added that other agencies, especially the Department of Roads, which is responsible for road maintenance, should address these problems.