In a study of 73 countries, air quality (measured as concentration of PM 2.5 particles) in Sweden was found to be the fourth best. Iceland and Finland was at the top. I think Iceland may jump up and down in the ranking depending on the status of their volcanos. At the bottom were Bangladesh, Pakistan and India.

Stockholm was ranked as the third best capital in the world with regards to air quality.

“Each year an estimated seven million people die early due to air pollution, and the PM 2.5 particles are one of the types of pollution that lead to the most significant health problems.”

» Sweden's air quality among the best in the world: study - The Local

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