Smog during Diwali can cause burning eyes, sore throat, coughing, and tightness in the chest. It can trigger asthma attacks and worsen respiratory conditions like COPD. Long-term exposure to polluted air increases the risk of chronic bronchitis, heart disease, and reduced lung capacity. Vulnerable groups, including pregnant women, children, and older adults, are particularly at risk. Even mental health and sleep can be affected, as poor air quality leads to fatigue and irritability.