In the stratosphere, roughly seven to 25 miles above Earth's surface, the ozone layer acts like sunscreen, shielding the planet from potentially harmful ultraviolet radiation that can cause skin cancer and cataracts, suppress immune systems and also damage plants. In the ‘70s, we discovered that chlorofluorocarbons – a type of gas used in fridges and aerosol sprays – were destroying the ozone layer, leading to a large hole forming over the Antarctic. Study co-author Professor Joanna Haigh, Co-Director of the Grantham Institute for Climate Change and the Environment at Imperial College London, said: “Ozone has been seriously declining globally since the 1980s, but while the banning of CFCs is leading to a recovery at the poles, the same does not appear to be true for the lower latitudes. The decreases in ozone are less than we saw at the poles before the Montreal Protocol was enacted, but UV radiation is more intense in these regions and more people live there,” said study co-author Joanna Haigh, Co-Director of the Grantham Institute at Imperial College London. The reason for the falling ozone at lower latitudes is not known, though scientists suspect a chemical used in paint stripper and a change in atmospheric circulation caused by climate change. Ozone hole recovery threatened by rise of paint stripper chemical Read more

Research published in July by Ryan Hossaini, at Lancaster University, UK, and colleagues showed that levels of a key VSLS, called dicholoromethane and used in paint stripper and aerosol sprays, have doubled in the last decade. Very short-lived substances could be the missing factor in these models.”

It was thought that very short-lived substances would not persist long enough in the atmosphere to reach the height of the stratosphere and affect ozone, but more research may be needed. The ozone layer has recovered at the poles, but the lower stratospheric ozone over the most populated latitudes has declined, according to a study published on Tuesday in the scientific journal Atmospheric Chemistry and Physics.
Scientists (in the article published in the journal Atmospheric Chemistry and Physics) warn that the ozone layer that protects people from the sun's ultraviolet radiation is recovering only over less populated areas.