Ozone is a gas. All ozone is bad for people s health. The ozone layer is in the part of the atmosphere that is closest to Earth.
Chlorine can damage ozone.
In order to make ozone, UV rays are necessary. The ozone hole is a huge hole in the Earth. The ozone hole was discovered more than one hundred years ago. Environmentalists think we need more research to save the ozone layer. UV rays cause skin cancer, cataracts, and other health problems.