Which substance is primarily addressed regarding ozone depletion?

CFCs, or chlorofluorocarbons, are the substances primarily addressed regarding ozone depletion due to their significant role in the destruction of the ozone layer. CFCs release chlorine atoms when they are broken down by ultraviolet (UV) radiation in the stratosphere, and these chlorine atoms catalyze the breakdown of ozone (O3) molecules, resulting in a decrease in the ozone layer that protects the Earth from harmful UV radiation.

The international community recognized the dangers posed by CFCs, leading to the Montreal Protocol in 1987, which initiated a phase-out of their production and use. While other substances like HFCs and HCFCs also have environmental impacts, they were not the original primary culprits identified for ozone depletion. Ammonia, although used in refrigeration applications, does not pose the same risk to the ozone layer as CFCs do.