The health effects of combustion pollutants range from headaches and breathing difficulties to death. When carbon monoxide accumulates in indoor air, it can cause headaches, dizziness, nausea,fatigue, excessive yawning, decreased hearing, heart palpitations, loss of appetite, and vomiting. The symptoms are frequently similar to influenza symptoms. Older people, pregnant women, and people with a history of heart disease are particularly sensitive to carbon monoxide exposure. Continued exposure to high levels of carbon monoxide can cause collapse, unconsciousness, and, in extreme cases, death.
Nitrogen dioxide can cause eye, nose, and throat and respiratory tract irritation.
Prolonged exposure has been shown to lower resistance to respiratory infection and can be damaging to respiratory tissue. Sulfur dioxide is particularly threatening to people with asthma, in whom it can constrict the airways leading to and from the lungs, making breathing difficult. People with lung disease and allergies may also have adverse reactions to sulfur dioxide fumes. Sulfur dioxide can also cause irritation of skin and eyes. Indoor air contamination by combustion pollutants is a significant health problem.