Ozone exposure

A team of scientists says the risk of dying from respiratory problems is more than 30% greater in metropolitan areas with the highest ozone concentrations than areas where ozone levels were the lowest.

Ground-level ozone, along with particulate matter, is a major component of smog. Ozone is a naturally occurring gas most prevalent high in the atmosphere, where it protects against harmful ultraviolet rays of the sun. However, ozone at ground level is produced when exhaust from cars, power plants, and other sources reacts chemically in sunlight. According to the Environmental Protection Agency, ground-level ozone can irritate breathing, decrease lung function, inflame airways, and worsen lung conditions such as asthma and emphysema.

People who have chronic obstructive pulmonary disease (COPD) or certain other lung conditions often take their medications using devices called a metered dose inhaler (MDI) or a dry powder inhaler (DPI). If you have COPD, your doctor will prescribe the medication you need to use in an MDI or DPI.