Bad air quality days are a heightened concern as ozone season begins in North Carolina.
Ozone season in the state lasts from March through October, when hot weather increases the prevalence of ground-level ozone.
Rafaella Vaca, education manager for the advocacy group CleanAIRE NC, said there are health effects from poor ozone days.
"Symptoms like shortness of breath, coughing and throat irritation as short term impacts," Vaca explained. "Over time, it can cause inflamed airways and worsen conditions like asthma, bronchitis, emphysema, and also increase your susceptibility to lung infections."
Ground-level ozone forms from chemical reactions between nitrogen oxides and organic compounds emitted from car exhaust, aerosols and manufacturing facilities.
Vaca acknowledged the effects of bad ozone are not often discussed, probably in part because it cannot be seen, even though it contributes to smog.
"It's not emitted directly from car emissions but it forms when pollutants come together in sunlight," Vaca noted. "It's a little bit more of a complicated process."
Vaca emphasized there are ways for people to protect themselves and others, including by driving less and using public transportation more often. People can also check the Air Quality Index and limit activities outside when levels are high.
Vaca argued regulatory agencies like the U.S. Environmental Protection Agency and North Carolina Department of Environmental Quality can do more to protect people.
"They need to consider all air emissions and contaminations that can affect your well-being," Vaca urged. "Unfortunately, that's not currently how this system works because each air pollution permit is evaluated as and only one pollution source to consider versus considering all of them at once."