Almost all of Southeast Asia—99.9 percent—is now considered to have unsafe levels of particulate pollution (PM2.5), reducing average life expectancy in 2021 by 1.6 years across the region relative to what it would be if the WHO guideline was met. In the eleven countries that make up this region, an estimated 1.1 billion total life years are lost due to air pollution. Residents living in some of the region’s largest cities are experiencing the greatest impacts. For example, the more than 6.8 million residents of Mandalay, Myanmar, are expected to lose 3 years and 5 months of life expectancy on average. More than 8.6 million people in Hanoi, Vietnam, are expected to lose 3 years. And, the more than 10.6 million people in Jakarta, Indonesia are expected to lose 2 years and 5 months. This pollution has been steadily increasing over the last two decades.
Despite the fact that tens of millions of people could lose years off their lives due to their pollution exposure, some countries—Indonesia, for example—were actually less polluted in 2021 than in previous years due to a calmer fire season. For example, 2019 was an active fire year in Indonesia, causing pollution to spike in the country and spread to its downwind neighbors like Malaysia. Comparatively, 2021 was calmer, reducing pollution across Indonesia by 16.3 percent and in Malaysia by 31.4 percent.
Fires cause a high degree of variability in pollution both temporally as well as geographically. For example, in 2021 areas of fire-prone northern Thailand–such as Phayao—experienced pollution levels that were 20 µg/m3 higher than levels in southern areas—such as Phuket. Those living in Phayao could live 11 months less than those in Phuket due to this pollution variation, if the disparity persists.