Exposure to Ozone Air Pollution Early in Life Linked to Asthma Risks: Study

Findings indicate that side effects ozone pollution exposure could increase childhood risks of asthma and wheezing by at least 30%.

New research shows that exposure to certain kinds of air pollution could significantly increase the risk that a child may suffer from chronic wheezing or asthma in the first few years of their life.

Approximately 6% of U.S. children suffer from asthma, making it the most prevalent chronic disease among this age group. Research has consistently identified air pollution as a leading contributor to asthma, particularly with ozone air polution.

Ozone frequently surpasses air quality standards in the U.S., and short-term exposure to it is associated with various respiratory health issues.

Now, findings published in the journal JAMA Network Open on April 2, indicate that exposure to ozone air pollution may increase the risk a young child experiences asthma and wheezing early in life by at least 30%.

For the study, researchers from the University of Washington in Seattle, led by Dr. Catherine J. Karr, conducted a multisite study involving nearly 1,200 children across six U.S. cities. They used data from the prospective ECHO-PATHWAYS consortium conducted from 2007 to 2023.

Children had complete airway surveys conducted, and full address histories were tracked from birth to 2 years old. All children were born full term. Researchers also examined exposure to a mixture of three common air pollutants: ozone, nitrogen dioxide and fine particulate matter (PM 2.5).

The findings indicate exposure to high levels of ozone during the first two years of life was linked with a higher risk of asthma and wheezing for those between the ages of 4 to 6 years old. The data indicated exposure to 2 parts per billion and higher ozone concentrations were linked to a 31% higher risk of asthma, and a 30% higher risk of wheezing among that group.

The researchers determined that average ozone concentrations were 26.1 parts per billion. When levels of ozone were higher than 25 parts per billion within the air pollution mixture the risk of asthma increased.

Ozone exposure is also associated with increased healthcare costs, added stress for families and long-term care costs.

Researchers suggest that the link between ozone and a heightened risk of asthma may stem from the fact that asthma can evolve as children grow older. Diagnoses often decrease with age, indicating that certain risk factors, including ozone exposure, may have a diminishing impact over time as children’s lungs develop further.

However, the team determined that more research is needed and called for health officials to pay more attention to the effects of long-term exposure to air pollution, especially ozone, since data focused on ozone and asthma is not often evaluated with other air pollutants. 

Health Effects of Air Pollution

Air pollution has long been linked to asthma, wheezing and other respiratory side effects.

A 2018 study by researchers from Harvard Medical School indicates that air pollution is linked to respiratory problems in older people as well. In that study, exposure to particulate matter and ozone increased the risk of acute respiratory distress syndrome (ARDS).

Another study, published in 2020 by researchers from Saint Luke’s Mid America Heart Institute, concluded exposure to ozone air pollution increases the risk of cardiac arrest.