Thailand has been ranked the world’s 23rd most polluted country and Bangkok ranks 24th in the list of cities with critical air quality globally, according to the 2018 World Air Quality Report.
In ASEAN, Thailand ranks the third most polluted country after Indonesia and Vietnam, which were placed 11th and 17th globally with average 42 and 32.6 microns of PM2.5 particulate respectively.
Bangladesh tops the world’s list as the most polluted country, but seven of the world’s 10 most polluted cities are in India, a country which ranks third most polluted globally.
Gurugram, a city about 30 km southwest of India’s capital of New Delhi, had the worst pollution levels globally in 2018.
The new data reveals the true scale of South Asian air pollution crisis: out of 20 most polluted cities in the world, 18 are in India, Pakistan and Bangladesh. The data also exposes nine South Asian cities that are even worse than Delhi. India, Pakistan, Bangladesh are among the most polluted countries in 2018.
The extent of air pollution levels in Pakistan has only recently been made publicly accessible through a community-driven network of air quality monitors established across the country
Conversely, Iceland is the cleanest country in the world with only 2.5 microns of PM2.5 dust particles.
“Air pollution steals our livelihoods and our futures. We want this report to make people think about the air we breathe, because when we understand the impacts of air quality on our lives, we will act to protect what’s most important.”
Yeb Sano, executive director of Greenpeace Southeast Asia
The World Health Organization estimates seven million people die every year due to air pollution, while non-fatal effects of over-exposure to PM2.5 particles include irregular heartbeat, aggravated asthma and decreased lung function.
“The 2018 World Air Quality Report is based on the review, compilation and validation of data from tens of thousands of air quality monitoring stations around the world. Now everyone with a cellphone has free access to this data via the AirVisual platform. This has also created demand for air quality monitoring in cities or regions where no public data is available. Communities and organizations from California to Kabul are supplementing governmental monitoring efforts with their own low cost air quality monitoring networks, and are giving everyone access to more hyper-local information.”
Frank Hammes, IQAir CEO
Findings from the report include:
- In South Asia: out of 20 most polluted cities in the world, 18 are in India, Pakistan and Bangladesh. This includes previously unseen data from Pakistan’s first public monitoring network of sensors. 
- In Southeast Asia: Jakarta and Hanoi are Southeast Asia’s two most polluted cities. With Beijing’s air quality getting better, Jakarta risks overtaking China’s famously polluted capital soon.
- In China: average concentrations in the cities in China fell by 12% from 2017 to 2018. Beijing ranks now as the 122nd most polluted city in the world in 2018.
- In the Western Balkans: 10 cities in the Western Balkans – Bosnia Herzegovina, Macedonia and Kosovo – and four in Turkey have PM2.5 levels more than 3 times the WHO guidelines. 8 cities in the Balkans are among the world’s most polluted 10%, out of all the cities with data.
- In U.S. and Canada: While average air quality is good in global comparison, historic wildfires had a dramatic impact on air quality in August and November, with 5 out of 10 most polluted cities in the world during August found in North America.
- Massive populations, including on continental Africa and South America, do not have adequate air quality measuring infrastructure.