Every December, Dr Nitipatana Chierakul, a specialist in respiratory medicine, notices the same pattern at his hospital department in Bangkok: his patients’ conditions will start to worsen.
Some present with chest pain or prolonged coughs. “Mostly they have difficulty breathing,” he says. For at least three months, patients who have pre-existing conditions can amount to up to 80% of his department’s caseload, he estimates.
The reason is the thick smog that blankets the city and other regions during the country’s cooler months.
The levels of pollution are even more severe in the north of Thailand. On Monday, Chiang Mai was listed as worst for air pollution in a live ranking by the Swiss air quality company IQAir, which includes data from about 100 cities around the world for which there is measured PM2.5 data. The smog, which has obscured views of Chiang Mai’s Doi Suthep mountain, led one doctor to warn on social media this month that tourists should not visit the city.
In Mae Sai, in the northern Chiang Rai province, local media footage on Monday showed thick yellow dust in the air as the concentration of particulate matter PM2.5 in the district reached 76.3 times the World Health Organization annual air quality guideline value, according to IQAir. Over the weekend, signs that read “Save Mae Sai” were hung in public places.
Air pollution in Thailand is generally worst during the cooler months, when seasonal agricultural burning occurs across the region, compounding the fumes already pumped out by transport and industry.
“[People] buy N95 masks, they buy air purifiers, they seal their houses, they get air quality monitors,” said Weenarin Lulitanonda, co-founder of the Thailand Clean Air Network. But these options are not affordable to everyone. “There’s huge inequality,” she added.
During the first nine weeks of 2023 alone, more than 1.32 million people in Thailand became ill because of diseases related to air pollution, according to government figures.
In Bangkok, a “pollution watch room” – with screens displaying weather patterns and pollution levels – was set up late last year by city authorities. One screen shows a map of live fires across Thailand and neighbouring countries: huge clusters of red dots, where farmers have burned their fields to clear crops, cover the region.
“If the dust level reaches level 3 [Bangkok health staff] will start to patrol, going out to provide masks and check on vulnerable groups,” said Wiruch Tanchanapradit, the director of air quality and noise management division at the Bangkok metropolitan authority, referring to a tiered-system used for monitoring pollution.
“Dust-free” rooms, which are sealed and contain air purifiers, have also been set up in nurseries, he said.
On bad days in the capital, warning messages are sent out through text messages and on social media advising the public to work from home, while signs in parks warn against outdoor exercise. At schools controlled by Bangkok authorities, coloured flags are used to remind children of whether it is safe to be outside.
Campaigners say the root causes of the problem remain unsolved, however – and that the large and powerful companies whose supply chains contribute to such pollution continue to dodge responsibility.
Thailand is a major producer of sugarcane and rice, and every season farmers burn their fields to clear the land. The practice continues despite burning bans because many farmers have no alternative, said Saroj Dokmaisrichan, a sugarcane farmer in Suphan Buri province.
“If you burn [sugarcane] you don’t have the leaves any more. It’s easier for the farmer to cut,” he says. Labour costs are lower and farmers are able to meet factory deadlines more easily. Saroj, who owns a large farm, took out a loan to buy machinery so that he no longer needs to burn his fields, but this is not an option for smaller farmers, he said. “It’s impossible for them to even buy a secondhand machine,” he added.
Dr Danny Marks, an assistant professor of environmental politics and policy at Dublin City university, said smallholder farmers were unfairly blamed for Thailand’s air pollution problem. Most are in contracts with major Thai agribusinesses, he added, which also have a footprint in neighbouring countries where burning occurs, with pollution blowing across borders.
Greater scrutiny is also needed of factories and industrial businesses, say researchers. There is no emissions database documenting the emission profiles of Thailand’s 140,000 factories. Instead, the law that regulated water and air waste was weakened in 2019, so that smaller factories do not need to report any of their pollution , said Marks.
“These factory owners, automobile companies, agribusiness owners are basically perpetuating slow violence, particularly on the poorest segments of society,” he said.
Weenarin, who has led efforts to develop a citizen-driven draft Thai Clean Air Act, said stricter legislation was needed. “This has to be in place to have any chance of fixing a solution,” she said. The bill was submitted to parliament over a year ago but has not progressed.
At Siriraj hospital, Dr Nitipatana worries the rates of disease will get worse if no action is taken. For his patients, the smog means a worsening quality of life and possibly a more severe prognosis.
Yet no political party has put air pollution at the front of their campaigns in the run-up to May’s elections, Nitipatana added. “The protection of the environment, especially the air, for everyone, should be one of the matters that they promise to the people,” he said.