Harmful substances in air pollution like cigarette smoke, gases from factories, and vehicle exhaust fumes can damage the respiratory system and cause respiratory diseases. Nicotine, tar, sulfur dioxide, carbon monoxide, and particulate matter are especially harmful as nicotine is addictive, tar and sulfur dioxide can irritate the lungs, carbon monoxide prevents oxygen intake, and particulate matter increases risks of asthma, bronchitis and pneumonia. Long-term exposure increases risks of lung cancer, heart disease, and emphysema which damages lung air sacs. Improving indoor and outdoor air quality through measures like avoiding smoking, pollution sources, and following emissions regulations can help protect respiratory health.