The gaping hole in the ozone layer of the atmosphere over the Antarctic was caused primarily by high concentrations of ozone-depleting chemicals called CFCs. The vast hole in the ozone was discovered by scientists in the 1980s, who upon discovering the dramatic loss in ozone cover, set to work determining a primary cause. They found excessive concentrations of chlorofluorocarbons (CFCs) in the area of concern; CFCs were frequently used as additives in spray cans and refrigerants, but are now banned in most areas of the world.
CFCs are synthetic materials, meaning that they are produced by humans and do not naturally occur. Like most synthetics, they do not break down, or biodegrade, when introduced to land, water and soil. CFCs are light in weight and escape into the atmosphere upon release. Like friends at a party, these chemicals seek like particles out, and form tight clusters in the sky. According to the Union of Concerned Scientists, CFCs can remain in the atmosphere for decades, even up to a century, after their release, depending on the specific type. CFCs bind to ice particles during the winter, then make their way into the sky in the spring, when released from ice particles by ultraviolet light. Then, they set to work preventing surrounding molecular bonds from absorbing UV radiation.