What replacement chemicals for CFCs have been found? Are they safe?
Hydrofluorocarbons (HFCs), hydrochlorofluorocarbons (HCFCs) and “Greenfreeze” chemicals (hydrocarbons such as cyclopentane and isobutane) have been the primary substitutes. The primary HFC used in automobile air conditioning, HFC-134a, costs about 3-5 times as much as the CFC-12 gas it replaced. A substantial black market in CFCs has resulted. HCFCs are considered a “transitional” CFC substitute, since they also contribute to ozone depletion (but to a much less degree than CFCs). HCFCs are scheduled to be phased out by 2030 in developed nations and 2040 in developing nations, according to the Montreal Protocol. HCFCs (and HFCs) are broken down in the atmosphere into several toxic chemicals, trifluoroacetic acid (TFA) and chlorodifluoroacetic acid (CDFA). Risks to human health and the environment from these chemicals is thought to be minimal (UNEP/WMO, 2002). HFCs do not cause ozone depletion, but do contribute significantly to global warming. For example, HFC-134a, the new refrigerant
