Air pollution in the Thai capital forced more than 350 schools to close on Friday, city authorities said, the highest number in five years.
Air pollution hits the Southeast Asian nation seasonally as colder, stagnant winter air combines with smoke from crop stubble burning and car fumes.
The level of PM2.5 pollutants—cancer-causing microparticles small enough to enter the bloodstream through the lungs—hit 108 micrograms per cubic meter by Friday, according to IQAir.
Interior Minister Anutin Charnvirakul ordered a ban on Thursday on stubble burning—intentionally burning leftover crops to clear fields—with those responsible risking legal prosecution.
In another bid to curb pollution, the capital’s Skytrain, metro, light rail system and bus services will be free to users for a week from Saturday, transport minister Suriya Juangroongruangkit told reporters.
“We hope this policy will help reduce pollution,” he said.
Cities in neighboring Vietnam and Cambodia also ranked high on IQAir’s most-polluted list on Friday, with Ho Chi Minh second and Phnom Penh fifth.
Cambodia’s environment ministry confirmed on Friday that the air quality in Phnom Penh and three other provinces had reached a “red level”, meaning highly polluted.
The ministry said in a statement that the air pollution was caused by climate change, waste incineration and forest fires, and urged the public to monitor their health and avoid outdoor activities.
Air pollution has closed schools across other parts of Asia recently—specifically Pakistan and India.
Nearly two million students in and around New Delhi were told to stay home in November after authorities ordered schools to shut because of worsening air pollution.
Pakistan’s most populated province, Punjab, closed schools in smog-hit major cities for two weeks in November, with thousands hospitalized as air pollutants hit 30 times the level deemed acceptable by the WHO.
Bangkok’s school closures come as UNICEF said in a report that 242 million children’s schooling was affected by climate shocks in 2024.
Climate change can worsen the problem of air pollution which is considered a “secondary impact of climate-induced hazards”, according to the report published Friday.