The ozone layer protects the earth from the sun's ultraviolet radiation, which is linked to skin cancer and other health risks.
Industries in northeastern China have spewed large quantities of an ozone-depleting gas into the atmosphere in violation of an international treaty, scientists say.
The ozone layer that protects life on Earth from deadly ultraviolet radiation is unexpectedly declining above the planet's most populated regions, a study says.
Environmental scientists raise concern at rising levels of gases that attack Earth's protective ozone layer, including manmade chemicals not covered by key UN treaty
