Adverse human health effects may be caused by a single pollutant or the synergistic effect, the acting together, of a number of pollutants. Individual pollutants have differing effects on human health, the chart below summarizes the effects of individual pollutants on human health.

Health Impacts of Carbon Mono Oxide (CO) :

Carbon monoxide, when entering the body, displaces the oxygen in the bloodstream and thus reduces the oxygen carrying capacity of the blood. This leads to oxygen starvation which can result in headaches and vomiting, can cause an individual to collapse and ultimately can lead to death. Carbon monoxide enters the bloodstream through the lungs and binds chemically to hemoglobin, the substance in blood that carries oxygen to cells.

In this way, carbon monoxide reduces the amount of oxygen reaching the body’s organs and tissues. People with cardiovascular disease such as angina, are most at risk from carbon monoxide. These individuals may experience chest pain and more cardiovascular symptoms if they are exposed to carbon monoxide, particularly while exercising.

People with marginal or compromised cardiovascular and respiratory systems (for example, individuals with congestive heart failure, cerebrovascular disease, anemia, chronic obstructive lung disease), and possibly fetuses and young infants, may also be at greater risk from carbon monoxide pollution. In healthy individuals, exposure to higher levels of carbon monoxide can affect mental alertness and vision.

Health Impacts of Ozone (O3) :

Ozone can irritate the respiratory system, causing coughing, throat irritation, and/or an uncomfortable sensation in the chest. It can lower your resistance to diseases such as colds and pneumonia.

Those who are most sensitive to its impact are the very young, the elderly, and those with pre-existing breathing problems. People with respiratory diseases whose lungs are more vulnerable to ozone may experience health effects earlier and at lower ozone levels than less sensitive individuals.

Ozone also makes people more sensitive to allergens, the most common triggers of asthma attacks. Even healthy adults doing heavy exercise or manual labor outdoors may experience unhealthy effects during high ozone periods. This is because, during physical activity, ozone penetrates deeper into the parts of the lungs that are more vulnerable to injury. Studies have shown that ozone can inflame and damage the lining of the lungs within a few days, the damaged cells are shed and replaced—much like the skin peels after a sunburn. However, if this type of inflammation happens repeatedly over a long time period, lung tissue may become permanently scarred, resulting in less lung elasticity, permanent loss of lung function, and a lower quality of life.

Health Impacts of Sulfur dioxide (SO2) :

Children and adults with asthma who are active outdoors are most vulnerable to the health effects of sulfur dioxide. The primary effect they experience, even with brief exposure, is a narrowing of the airways (called bronchoconstriction), which may cause symptoms such as wheezing, chest tightness, and shortness of breath. Symptoms increase as sulfur dioxide concentrations and/or breathing rates increase. When exposure ceases, lung function typically returns to normal within an hour.

At very high levels, sulfur dioxide may cause wheezing, chest tightness, and shortness of breath in people who do not have asthma. Long-term exposure to both sulfur dioxide and fine particles (PM) can cause respiratory illness, alter the lung’s defense mechanisms, and aggravate existing cardiovascular disease. People who may be most susceptible to these effects include individuals with cardiovascular disease or chronic lung disease, as well as children and the elderly.

Health Impacts of Particulate Matters (PM) :

Both fine and coarse particles can accumulate in the respiratory system and are associated with numerous health effects. Coarse particles can aggravate respiratory conditions such as asthma.

Exposure to fine particles is associated with several serious health effects, including premature death. Adverse health effects have been associated with exposures to PM over both short periods (such as a day) and longer periods (a year or more). When exposed to PM, people with existing heart or lung diseases—such as asthma, chronic obstructive pulmonary disease, congestive heart disease, or ischemic heart disease—are at increased risk of premature death or admission to emergency rooms.

The elderly also are sensitive to PM exposure. They are at increased risk of admission to emergency rooms and premature death from heart or lung diseases. When exposed to PM, children and people with existing lung disease may not be able to breathe as deeply or vigorously as they normally would, and they may experience symptoms such as coughing and shortness of breath. PM can increase susceptibility to respiratory infections and can aggravate existing respiratory diseases, such as asthma and chronic bronchitis, causing more use of medication and more doctor visits.