A gas that can be found in two places. Ozone is not created directly, but is formed when nitrogen oxides and volatile organic compounds mix in sunlight. That is why ozone is mostly found in the summer.
Nitrogen oxides come from burning gasoline, coal, or other fossil fuels.
There are many types of volatile organic compounds, and they come from sources ranging from factories to trees. Ozone near the ground can cause a number of health problems. Ozone can lead to more frequent asthma attacks in people who have asthma and can cause sore throats, coughs, and breathing difficulty. It may even lead to premature death. Ozone can also hurt plants and crops.