Note: Data as of 5 pm IST on October 23. The AQI score is based on the US system where a score of between 0-50 is good, 51-100 is moderate, 101-150 is unhealthy for sensitive groups, 151-200 is unhealthy, 201-300 is very unhealthy and >301 is hazardous. International numbers compare major global cities, data shows top seven.