Exposure to Low Ambient-Air Ozone May Cause Adverse Effects in Asthma

After careful consideration, the American Academy of Allergy, Asthma & Immunology canceled its annual meeting that was to take place in Philadelphia, Pennsylvania from March 13 to 16, because of concerns regarding the coronavirus disease 2019 (COVID-19) outbreak. Although the live events will not proceed as planned, our readers can still find coverage of research that was scheduled to be presented at the meeting.

Exposure to low ambient air ozone levels may produce adverse health effects in children with asthma, according to research that was intended to be presented at the 2020 Annual Meeting for the American Academy of Allergy, Asthma & Immunology (AAAAI).

Ozone is a highly common trigger for asthma attacks and provokes a rapid decrease in forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV₁). Ozone dose is dependent on exercise intensity and on the concentration and duration of exposure. The objective of this study was to determine whether exposure to ambient air ozone concentrations without exercise led to changes in lung function.

In this randomized, double-blinded crossover study, researchers evaluated 14 healthy, nonsmoking volunteers (mean age, 32 years). While at resting state, participants were exposed to either filtered clear air or to an average ozone concentration of 0.07 parts per million. Participants underwent spirometry before and after exposure, and paired T-tests were used to compare the effect of ozone with filtered air in predicted FEV₁ and FVC.

When exposed to ozone, a decrease of 2.8±1.0 points in percent predicted FEV₁ occurred compared to filtered air (P =.02). Researchers also observed a significant reduction in postozone to postfiltered air predicted FVC of 1.5±0.5 points (P =.007), although the change from baseline percent predicted FVC (1.5±0.9 points lower with ozone) had no significance when comparing ozone to filtered air (P =.1).

The researchers concluded that exposure to low ambient air ozone levels may produce adverse health effects in susceptible populations including children with asthma, given that healthy adults experienced a decrease in lung function following low-level ozone exposure even when sedentary.

Reference

Hernandez M, Vadlamudi A, Ivins S, Chason K, Almond M, Peden D. Low level ozone exposure at rest causes changes in lung function among healthy volunteers. J Allergy Clin Immunol. 2020;145(Suppl 2):AB82.

Visit Pulmonology Advisor‘s conference section for more coverage from AAAAI 2020.