The primary cause of ozone depletion is the release of chlorofluorocarbons (CFCs) and other ozone-depleting substances into the atmosphere. These compounds break down ozone molecules in the stratosphere, leading to the thinning of the ozone layer that protects Earth from harmful ultraviolet (UV) radiation. Increased UV exposure can lead to serious health and environmental issues, including skin cancer, cataracts, and detrimental effects on wildlife and plants. International agreements like the Montreal Protocol have been instrumental in reducing CFC emissions and promoting ozone layer recovery.