The capital, which has a population of just over 96,000 residents, and hosts a high concentration of business and employment, ranked “good” for its concentration of fine particulate matter, or PM2.5 (8.3μg/m3) over the past two years.

Nordic cities dominated the top ten with Sweden’s Umea at number one. Luxembourg was sandwiched between Darmstadt in Germany at 46 and Annecy in France at 48. All three had the same level of fine particulate matter but with denser populations.

The World Health Organization has a recommended threshold for exposure to PM2.5 of 10μg/m3. Under its clean-air policies, the EU’s limit value is 25 μg/m3.