Earth, Climate & Environment

Chlorofluorocarbons (CFCs): Harmful Effects

CFCs damage the ozone layer when they escape from sources such as leaky car air conditioners, discarded plastic-foam egg cartons, and old home air conditioners crushed in a landfill. The CFCs drift up to the stratosphere, an upper layer of the atmosphere where strong ultraviolet radiation from the Sun breaks them down. As they break down, they release chlorine, which depletes the protective ozone layer. A single chlorine atom can destroy over 100,000 ozone molecules.

Ozone absorbs ultraviolet radiation. When the ozone layer thins, more of a harmful type of ultraviolet radiation called UVB reaches Earth’s surface. Studies show that UVB radiation can cause skin cancer. UVB has also been linked to cataracts of the eye and to suppression of the immune system. Fish, shrimp, crabs, amphibians, and other animals that live in or around water—including phytoplankton, microscopic organisms that form the foundation of aquatic food webs—are all at risk from UVB radiation.