The heavily polluted air in Delhi poses severe health risks, particularly for individuals with pre-existing respiratory and cardiovascular conditions. Prolonged exposure to high levels of air pollution can lead to respiratory illnesses, cardiovascular diseases, and reduced life expectancy. Vulnerable groups, including children, the elderly, and those with chronic health conditions, are at the highest risk. In Lucknow, moderate pollution levels also pose health concerns, while Mumbai and Chennai have relatively better air quality but still require caution during outdoor activities.