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This means that breathing low concentrations of freon from a leaking refrigerator or air conditioner over a long period of time is unlikely to have a cumulative effect, and thus few, if any, long term health effects.
window air conditioner image by Aaron Kohr from Fotolia.com. Freon is the trade name for a group of man-made chemicals called chlorofluorocarbons (CFCs). CFCs contain chlorine, fluorine and carbon and are often found in air conditioners and refrigerators. The manufacturing and use of Freons is restricted and is gradually being phased out. People are usually exposed to Freon by accidentally or deliberately breathing it in.