Some science behind the scenes

Freon/CFCs

A chlorofluorocarbon (CFC) is an organic compound that contains carbon, chlorine, and fluorine, produced as a volatile derivative of methane and ethane. A common subclass is the hydrochlorofluorocarbons (HCFCs), which contain hydrogen, as well. They are also commonly known by the DuPont trade name Freon and Halon. The most common representative is dichlorodifluoromethane (R-12 or Freon-12).

Freon is DuPont's brand name for CFCs, HCFCs and related compounds. Other commercial names from around the world include Algofrene, Arcton, Asahiflon, Daiflon, Eskimo, FCC, Flon, Flugene, Forane, Fridohna, Frigen, Frigedohn, Genetron, Isceon, Isotron, Kaiser, Kaltron, Khladon, Ledon, Racon, and Ucon.

They have multiple uses.  Many CFCs have been widely used as refrigerants, propellants (in aerosol applications), and solvents. They are used in fire extinguishers and in fire-fighting and as a fumigant.  Its use in refrigeration arose because a new refrigerant was needed that was both non flammable and of a low boiling point and for it to be generally non-reactive. In a demonstration for the American Chemical Society, Thomas  Midgley flamboyantly demonstrated all these properties by inhaling a breath of the gas and using it to blow out a candle in 1930.

The manufacture of such compounds is being phased out by the Montreal Protocol because they contribute to ozone depletion.  One of CFCs' most attractive features—their low reactivity— is key to their most destructive effects. CFCs' lack of reactivity gives them a lifespan that can exceed 100 years, giving them time to diffuse into the upper stratosphere.

By 1987, in response to a dramatic seasonal depletion of the ozone layer over Antarctica, diplomats in Montreal forged a treaty, the Montreal Protocol, which called for drastic reductions in the production of CFCs. On March 2, 1989, 12 European Community nations agreed to ban the production of all CFCs by the end of the century. In 1990, diplomats met in London and voted to significantly strengthen the Montreal Protocol by calling for a complete elimination of CFCs by the year 2000. By the year 2010 CFCs should be completely eliminated from developing countries as well.

But CFCs are unfortunately still available. Because the only CFCs available to countries adhering to the treaty is from recycling, their prices have increased considerably. And once prices increase illicit production or recycling often ensues.  A UNEP (United Nations Environmental Programme) 2006 report titled "Illegal Trade in Ozone Depleting Substances" highlighted this problem. UNEP estimates that between 16,000–38,000 tonnes of CFCs passed through the black market in the mid-1990s. The report estimated between 7,000 and 14,000 tonnes of CFCs are smuggled annually into developing countries. Asian countries are those with the most smuggling; China, India and South Korea were found to account for around 70% of global CFC production.
Freon effects

According to their material safety data sheets, CFCs and HCFCs are colourless, volatile, relatively non-toxic liquids and gases with a faintly sweet ethereal odour.
Overexposure may cause dizziness, loss of concentration, central nervous system depression and/or cardiac arrhythmia.

Vapors displace air and can cause asphyxiation in confined spaces.  Ultimately the main cause of any sort of experience is hypoxia with a real risk of coma or death.  At high concentrations you may get delirium from being poisoned.

Observations

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