Everyone can be exposed to ground-level ozone
Ozone is a gas that is naturally found in earth’s upper atmosphere, where it forms the ozone layer. The ozone layer blocks some of the sun’s harmful ultraviolet (UV) rays.
While Ozone layer protects us from getting all the UV rays, ground-level ozone is a pollutant that can harm the environment, crops, and human health. It is ozone in the lower atmosphere, close to the Earth’s surface. This is one of the main components of smog. Ground-level ozone is formed when sunlight and heat cause chemical reactions between nitrogen oxides and volatile organic compounds .
Volatile organic compounds are pollutants released by motor vehicles, factories and power plants, and chemicals such as paints and cleaners. Since we live in a modern world and we are exposed to all these wherever we go.
Source: Department of Health and Human Services.