What compounds cause ozone depletion in the stratosphere?

Research in the 1970s linked chlorofluorocarbons (CFCs), such as freon, to the depletion of the ozone layer. In 1978, the use of CFC propellants in spray cans was banned in the United States. In 1987, the Montreal Protocol was signed and the signatory nations committed themselves to a reduction in the use of CFCs and other ozone-depleting substances.

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