According to data from the World Health Organization’s global PM2.5 database, Kathmandu’s particulate pollution (PM2.5) averaged 49 micrograms/m3 in 2013. That fits nicely with 2017 data I analyzed from the US Embassy’s PM2.5 monitor from Kathmandu (49 micrograms). How bad is that? That’s just about double the WHO’s 24-hour limit of 25 micrograms. That means, if your lungs are in Kathmandu, they’re breathing in dangerous levels of tiny particles on most days.
In the summer, Kathmandu’s PM2.5 falls to very close to the WHO annual limit. But in the winter, it shoots up to as high as 9 times that amount.
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