Delhi overtakes Lahore as world's most polluted major city as air quality deteriorates
India’s capital, Delhi, overtook Lahore to become the world’s most polluted city on Friday, with air quality reaching hazardous levels and visibility dropping as smog blanketed the city of 20 million people. Earlier, Delhi’s air quality index (AQI) stood at 334, categorised as “hazardous”, making it the most polluted major city globally, according to Swiss air quality monitoring group IQAir , which measures pollution levels based on the concentration of pollutants. An AQI…