Destroys the ozone layer
CFC's react with ozone to deplete it. They decompose it.
CFC's react with ozone. They decompose it and thus it gets depleted.
CFC's are highly reactive compounds. They react with ozone and deplete it.
For years people thought chlorofluorocarbons were harmless. Then someone discovered they destroyed the ozone in the ozone layer. The ozone layer stops the most dangerous of the sun's rays. Those rays cause cancer when they strike an individual. The continued use of chlorofluorocarbons would wipe out life on earth that lives above the ground or above sea level from cancer. As a result, it became illegal to make machinery that used them. When machines that used them had to be repaired, a different refrigerant had to be used.