There are a number of culprits that increase the amount of particle pollution in the air. These include: old diesel engines and the growing number of cars on the roads, the ‘temperature inversion affect – where cold air along with pollution is trapped close to the surface of the Earth, the burning of rubbish in cities and landfills and coal power plants. However, the ‘Smokey Season’ in Thailand is especially concerning. It starts to blow in during January and February and continues until the rains come in May. In 2019, the Air Quality Index (AQI) in Chiang Mai was measured at a staggering 375 – the highest in the world – and made international news, causing tourism to drop by 30% last year.

The ‘Slash and Burn’ method has been used by rural farmers around the world for 12,000 years, since the agricultural revolution. Burning harvested crops help to remove vegetation, drive away pests, and provide a burst of nutrients for planting. A specific reason why Thai Locals set fire to the forests is to ferret out wildlife and pick an exotic mushroom, which sprouts from the charred ground. These dark, spherical hed thob are sold by foragers from makeshift roadside kiosks for as much as 1,000 baht ($33) a kg.
Today, between 200 and 500 million people use this method, roughly 7% of the world’s population – a few hundred years ago, this wasn’t such an issue, as after one or two growing seasons, the field was fallowed, or set aside to rest and the forest would return and the cycle was repeated – now, in much larger scale – it causes persistent environmental problems including deforestation, erosion, air pollution and nutrient and biodiversity loss.

So what can WE do about it?
Donate to or volunteer with organisations and firefighters
Volunteers Without Borders Foundation – We have set up our first agroforestry project in Mae Wang to reduce the spreading of fires, restore the community forest to its optimum levels in order that it may capture as much carbon as possible, and protect its biodiversity. We develop firebreaks, grow Non-Timber Forest Products, use sustainable agriculture and create partnerships with villagers to incentivise them to protect their forests. We welcome donations and have monthly volunteer opportunities for the project.
Warm Hearts Foundation – Their 5-year plan is based on incentive to help stop the smoke from agricultural fires. They are training farmers to convert crop waste into biochar and developing marketable products like biochar fertiliser and biochar briquettes. You can make a donation on their website.
Conserve Natural Forests – An important part of their project is to restore damaged landscapes by planting a variety of native species and managing restored land for several years before the regenerated forest can sustain itself. Last year they planted 190,000 trees in the Mae Hong Son province of Thailand with the help of the Thai army and the local community. This year, their goal is to plant a million trees. The donations they receive offset carbon and interns and volunteers can work with them all year round.
Food For Change – They are planting specific trees to potentially absorb and trap the tiny particulate matter in the air. Volunteers are invited to help plant trees together to control air quality appropriately by using perennial, dense shrubs and plants like Cocoa, Siamese Cassia and Tha Ling Phling that can also be consumed or sold by the local residents.
Blue Sky for Chiang Mai – support or volunteer for this group who work with various universities, firefighters and national park rangers to put out fires, stop the sale of Hed Thob mushrooms, pick up trash and raise awareness.

Wear a mask and invest in an air purifier
The World Bank estimated that air pollution related deaths in Thailand have risen to nearly 20,000 in the past 20 years. They also estimated that each year, 2 million people die prematurely from the poisonous gases that make up smog. Symptoms can range from chest pain, sore throats, headaches, eye problems, nausea and increased sensitivity to allergens to aggravated heart disease, reproductive/neurological disorders and even cancer. P.M 2.5 (particulate matter) are smaller than red blood cells, so they can invade any organs the blood reaches, especially the lungs, heart and brain.
Protect yourself and your family from PM 2.5 particles by wearing a mask. Look for masks that specifically advertise a filter grading of at least N95, they should fit snugly around the nose and mouth with no open gaps on the sides to allow unfiltered air in. Many pharmacies in the city have these masks, or you can order them from Lazada online, make sure to replace the filters often.
Invest in or make your own air purifier and grow air purifying plants in your house and office. Make sure to also seal all your windows and doors and use a filtered air conditioning unit so that you can breathe freely while inside. Here is a list of public spaces in Chiang mai with air purifiers.
Check the air quality index and avoid going outdoors where possible. If it the air is seriously affecting you or your family’s health, leave the city for a few months.
“In mid-March, the city with the worst air pollution in the world wasn’t an industrial powerhouse populated by millions. It was Chiang Mai, the tourist-friendly cultural center in northern Thailand. “
Washington Post, 2019

Report fires and vehicles
Officially there is a 60-day no-burning rule until April 15, but enforcement is difficult because burning is considered a “way of life” here and it is widespread. Do your part by taking a photo, recording the date, time and location and reporting it to the Fire Reports Chiang Mai Facebook page. Firefighters and government organisations will attempt to put them out and fine the farmers responsible.
You can also report vehicles that are billowing black or grey smoke out of their exhausts – make a note of their number plate, type of vehicle and location and report it to DLT Chiang Mai or the Kingdom’s Pollution Control Department.
Educate.
Share information with your friends and community on Social Media, join climate marches, talk to people, volunteer in person, plant trees in friend’s gardens, take the bus, reduce air travel, support local farmers and markets and try to reduce your support of large companies.
Further reading:
- Stief, Colin. “Slash and Burn Agriculture Explained.” ThoughtCo, Oct. 15, 2019, thoughtco.com/slash-and-burn-agriculture-p2-1435798.
- RAYGORODETSKY, GLEB . “These Farmers Slash and Burn Forests—But in a Good Way.” National Geographic, Mar. 8, 2016 nationalgeographic.com/news/2016/03/160303-thailand-farmers-slash-and-burn-forests-climate-environment
- www.biothai.org/
- https://thethaiger.com/hot-news/air-pollution
- Kundhikanjana, Worasom. “Identifying the Sources of Winter Air Pollution in Bangkok Part II” Mar 31, 2019. https://towardsdatascience.com/identifying-the-sources-of-winter-air-pollution-in-bangkok-part-ii-72539f9b767a
- https://www.nytimes.com/2020/01/13/science/air-pollution-fires-genes.html
- https://www.facebook.com/smokethedocumentary/