Ozone is one of the six common air pollutants identified in the Clean Air Act. Exposure to unhealthy levels of ozone air pollution continues to make breathing difficult for more Americans across the country than any other single pollutant. Ozone can irritate throat and lungs, make it more difficult to breathe, provoke asthma attacks and damage the lining of lungs.

What Is Ozone?

Ozone (O₃) is a unique form of oxygen made up of three oxygen atoms, unlike the oxygen we breathe (O₂), which has only two atoms. The ozone layer found high in the upper atmosphere shields us from much of the sun's ultraviolet radiation. However, ozone air pollution at ground level where we can breathe it causes serious health problems. Ozone aggressively attacks lung tissue by reacting chemically with it.

Where Does Ozone Come From?

Pollution from cars, trucks, power plants, factories, paint, hairspray and many other pollution sources contribute to the formation of ozone. Ground-level ozone develops in the atmosphere from gases. Two kinds of pollution—nitrogen oxides (NOx) and volatile organic compounds (VOCs)—react in the air in the presence of sunlight to produce ozone. NOx is produced primarily when fossil fuels like gasoline, oil or coal are burned such as in power plants, motor vehicles, furnaces and other sources of high-heat combustion. VOCs are released into the air from some common consumer products like paint and when household chemicals like paint thinners and solvents evaporate. VOCs are also emitted from motor vehicles, chemical plants, refineries, factories, and gas stations. This pollution can travel with the wind over long distances, creating air quality problems far downwind of pollution sources.

Who Is at Risk from Ozone exposure?

Anyone who spends time outdoors where ozone pollution levels are high may be at risk. The risks increase for individuals spending more time in environment with greater ozone levels.

The groups most at risk are:

Active children, because they spend a more time outside playing hard and are more likely to have asthma.
Active adults, because vigorous outdoor work or exercise exposes them to more ozone.
People with respiratory disease, because diseases like asthma make the lungs more open to the damaging effects of ozone.
Those with unusual sensitivity, some healthy adults are more susceptible to the effects of ozone for no obvious reason.
People of lower socioeconomic status

Current National Ambient Air Quality Standard for ozone is 70 parts per billion (ppb) measured over eight hours

How Ozone Pollution Harms Your Health?

Exposure to elevated levels can cause a variety of respiratory issues, such as:

Irritation of the airways: Ozone can cause the airways to become inflamed and irritated, leading to coughing and discomfort.
Aggravation of lung diseases: For people with asthma, bronchitis, or other respiratory conditions, ozone can worsen symptoms.
Decreased lung function: High levels of ozone can reduce lung function, making it more difficult to breathe deeply.
Increased risk of respiratory infections: Ozone exposure can make people more susceptible to lung infections.
Long-term health risks: Prolonged exposure, particularly for children, the elderly, and those with pre-existing conditions, can lead to chronic respiratory diseases, reduced lung capacity, and potentially even cardiovascular problems.