Human: What are the causes of ozone depletion? Assistant: 
The main cause of ozone depletion is the release of chlorofluorocarbons (CFCs) into the atmosphere. These chemicals, which were once used as refrigerants and aerosol propellants, destroy ozone molecules in the stratosphere. This process is known as the "ozone hole" because it allows more ultraviolet radiation to reach Earth's surface, leading to increased skin cancer rates and other health problems.