New Delhi is world's most polluted capital for third straight year: Study

New Delhi was the world's most polluted capital for the third straight year in 2020, according to IQAir, a Swiss group that measures air quality levels based on the concentration of lung-damaging airborne particles known as PM2.5. India was home to 35 of the world's 50 most polluted cities, according to IQAir's 2020 World Air Quality Report, which gathered data for 106 countries.