Summer months can be tough on people with asthma, which affects more than 20 million Americans. Poor air quality caused by a combination of ground-level ozone and air pollution can worsen asthma symptoms, triggering wheezing, coughing, trouble breathing, and even leading to hospitalization in serious cases. Newspapers, websites, and TV news broadcasts often warn of so-called “ozone-advisory,” “ozone-alert,” or “ozone-action” days, when sensitive groupsthose with asthma and other respiratory conditionsshould stay indoors because potentially dangerous smog conditions are likely.
Ozone is the primary ingredient in urban smog, generated when sunlight hits pollutants spewed by cars, chemical plants, industrial boilers, refineries, and other sources. It occurs naturally in the Earth’s upper atmosphere, but when it’s released at ground level, it becomes a harmful outdoor pollutant. Because sunlight abounds during summer months, summer is often a highly irritating time for the lungs of asthmatics, says LeRoy Graham, a pediatric pulmonologist based in Atlanta, Ga.
On ozone-alert days, asthmatics tend to experience more lung inflammation. When this happens, “they’re more likely to have to seek unscheduled care,” Graham says. Because of this, asthmatics should have a plan to lessen the chances of an attack on poor air-quality days, and know what to do if an attack occurs.