11 July 2024

Thailand recently brought the PM2.5 situation in Thailand to the attention of international researchers at the conference titled the “Role and Fate of Forest Ecosystems in a Changing World” organized by the International Union of Forest Research Organizations (IUFRO) and hosted by King Mongkut University of Technology Thonburi (KMUTT).

Held in Thailand for the first time in IUFRO’s 130-year history, the conference brought together over 80 researchers specializing in air pollution and climate change from all over the world to share and discuss new findings and interesting issues around forest ecosystems and air pollution. 

As a keynote speaker at the opening of the conference, Weerasak Kowsurat, former Minister of Tourism and Sports, told the participants that PM2.5 was only added to Thai vocabulary in 2018 though it had been around for far longer. He also stressed the seriousness of its impact. 

He cited open burning as an important cause of PM2.5 dust, not only in Thailand, but in the entire region. Every year, in the dry season, hotspots occur mostly in the north of Thailand and neighboring countries, especially in Myanmar, where the forest remains thick. Over 60% of hotspots occur in the forest with no road access, making it difficult to douse the flames. 

Since such hotspots are caused by humans, the Thai government has taken several measures, including enacting laws and putting effective implementation in place in an attempt to ease the situation.  

“But the most important tool is to communicate,” said Weerasak. “The government is trying to communicate the impact of open burning and PM2.5 on the environment and health. This helps a lot but there is a lot more work to be done.” 

Asst. Prof. Prapat Pongkiatkul, Head of Environmental Engineering Department, KMUTT, spoke of the PM 2.5 situation in Bangkok and the metropolitan region (BMR), noting that the situation usually deteriorated in winter, especially January and February, and improved in summer and the rainy season (May-October). One of the main reasons for high PM2.5 during winter is the inversion that traps air pollution. This cycle is repeated every year but the degree of severity differs. 

He noted that statistics showed that PM2.5 in BMR mainly came from traffic (30-40%), open biomass burning (20-30%), chemical reaction in the atmosphere (10%) and industrial emissions.   

“Traffic emission is the No.1 source of PM2.5 in BMR. Statistics from Thailand’s Ministry of Transport show that the most popular mode of transport in Bangkok is the personal car which accounts for 56%. The second most popular is bus travel, which is around 35%, while mass transit systems like the skytrain and the subway are about 4%. That’s why PM2.5 in BMR is high during rush hours in the morning and evening, especially Monday morning and Friday evening,” he said. 

However, while traffic emissions dropped significantly during the COVID lockdowns in 2020 and 2021, there was no proportionate decrease in PM2.5.  

“This tells us that a lot of PM2.5 in the BMR comes from other areas away from the urban mass. If we want to solve this problem, we need to take a holistic approach rather than focusing on any particular issue,” he added. 

Those seeking medical services as a result of PM2.5 peak in Thailand. not only in the BMR, in March and April when the number of hotspots or forest fires are at their highest. 

In Bangkok, there is a significant increase in number of patients suffering from stroke, as well as eye and skin irritation in winter, which is likely related to air pollution. Young children are one of the most vulnerable groups. 

“In Thailand, there are over three million children aged under nine who are living in high-risk areas where PM2.5 exceeds the World Health Organization’s limit. Thailand recently built some 50 Clean Air Shelters for young children but many more children still live outside,” Prapat pointed out. 

“China has successfully solved a similar problem and it took them eight years. We know it takes time so we need to take action now,” he said. 

 By Thai PBS World Feature Desk