Millions of People Are Getting Sick From This Country’s Toxic Air

This year’s “haze season” in Thailand saw 2.4 million people visiting hospitals for health problems linked to air pollution.
Koh Ewe
Over the past month, Chiang Mai in northern Thailand was ranked as the world's most polluted city. Photo: Lillian SUWANRUMPHA / AFP​
Over the past month, Chiang Mai in northern Thailand, was ranked as the world's most polluted city. Photo: Lillian SUWANRUMPHA / AFP

In Thailand, 2.4 million people have sought treatment at hospitals for health problems linked to air pollution since the start of the year, health officials said last week, as toxic smog has smothered some northern provinces for months. 

While “haze season” is a familiar annual occurrence for residents—caused in part by forest fires and farmers burning their fields—this year’s smog appears to be especially hazardous, being exacerbated by a record-breaking heatwave in the region and a post-pandemic resurgence in farming activity.


Chiang Mai, a tourist magnet in northern Thailand, is known to top the charts during “burning season” for having some of the worst air quality in the world. From 2017 to 2019, annual average PM2.5 levels in Chiang Mai increased from 22.7 to 32.3 micrograms per cubic meter. PM2.5 refers to particles that are 2.5 microns or less in diameter, which are able to enter the bloodstream and lodge deep in the lungs, triggering health problems such as asthma and bronchitis, as well as causing long-term issues such as cancer. 

Over the past month, the city was again ranked the world’s most polluted city, with PM2.5 levels exceeding 200 micrograms per cubic meter on many days—around 14 times the World Health Organization’s safety guideline. 

“I am concerned about the impact of air pollution in the long term both on human health and the environment. As we know, health impacts are both acute and chronic,” Somporn Chantara, an associate professor who heads the Environmental Science Research Center at Chiang Mai University, told VICE World News.

“In terms of health, vulnerable groups of people including low-income people as well as sensitive groups such as children, elderly, and patients with respiratory disease… They need protection, [such as] safety zones and masks, to avoid air pollution.”

Local media reported that hospitals in Chiang Mai have struggled to deal with the influx of patients, and many were not able to secure treatment due to the crowding.


A thunderstorm on Sunday brought some respite from the punishing smog, as Chiang Mai finally saw a drop in PM 2.5 levels according to IQAir, which publishes air quality data around the world. But on Wednesday, the city’s air rose back to unhealthy levels. 

The thick haze, which has been lingering since early March, has dealt a blow to Chiang Mai’s tourism industry, as travelers shun the city in fear of the hazardous air. Authorities have tried to reduce pollution by spraying water into the air and with cloud seeding—a process of implanting particles into clouds to trigger rain. But air pollution levels have continued to hover at hazardous levels. 

On April 10, about 1,700 Chiang Mai residents lodged a class action lawsuit against Thai authorities for failing to deal with the smog, arguing that the pollution is shortening their lives. The lawsuit against Prime Minister Prayut Chan-o-cha and the National Environmental Board was accepted by the Chiang Mai Administrative Court on Friday.

But it’s not just Thailand that’s choking. Extreme pollution is a regional problem, with Thailand and its northern neighbors long struggling to rein in agricultural burning. Since the start of the year, Myanmar has topped the region with 275,000 hotspots, areas with unusually high temperatures that may indicate active fires. Laos has had 220,000 hotspots, while Thailand has had 154,000—12,182 of them in Chiang Mai


Prayut and his counterparts in Laos and Myanmar met in a video conference in early April to discuss how they could mitigate the problem. The leaders agreed to the need for transnational cooperation and public education on air pollution. 

But experts note that the solution is not so clear-cut in Thailand. Small-scale farmers, who clear their land by burning fields and agricultural waste, are largely responsible for the haze. But most of them are left with little choice due to financial burden, according to Weenarin Lulitanonda, the co-founder of Thailand Clean Air Network. 

With expensive machinery like harvesters that shred crop waste out of their reach, crop burning is an affordable way to ready their land for more farming, despite temporary government bans against the practice. Other than crop burning, motor vehicles, industrial facilities, and forest fires also contribute to the toxic air.

“[Small-scale farmers] are the scapegoat most often in the media for the burning practices, but the reality of the matter is, until there is a solution where they can put food on the table and be viable operationally, it’s going to be very difficult for them because there’s no alternate solution to the burning,” Weenarin told VICE World News.

The Thailand Clean Air Network is running a petition calling for a bill to strengthen authorities’ response to pollution and protect Thai people’s right to clean air.

“This is an issue that really has to transcend politics, that has to transcend business interests,” Weenarin said. “People in Asia, here in Thailand and also in neighboring countries… are all jointly suffering. And the highest cost we’re paying for it is our lives.”

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