Relic: Chlorofluorocarbons

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Nothing strikes more fear into the environmentalist than the word chlorofluorocarbon (CFC). While used for many years, CFCs have been cited as a major contributor to global warming in recent times. CFCs have contributed to opening a hole through the ozone (O3) layer over Antarctica in the 1970s. The ozone layer is defined as an area of  the Earth’s stratosphere that absorbs most of the Sun’s ultraviolet (UV) radiation. Scientists confirmed the existence of the hole in the ozone layer in a study by the British Antarctic Survey. Researchers Joe Farman, Brian Gardiner and Jonathan Shanklin confirmed the “Ozone Hole” in May 1985, prompting scientists to find a solution to close it.

The Montreal Protocol of 1987 (entered into force in 1989) severely cut back the use of CFCs. The agreement has undergone revisions in 1990, 1991, 1992, 1993, 1995, 1997, 1998, 1999 and most recently in 2007. The Montreal Protocol was also famous because of its universal ratification by the members of the United Nations. But there is an interesting history behind why CFCs became one of the most preferred chemicals for industrial use before being severely restricted as a result of the damage it did to the environment.

A CFC is an organic compound that contains carbon, chlorine and fluorine, which is produced as a volatile derivative of methane, ethane and propane. To the non-scientist, CFC was known as freon, which was a registered trademark of the DuPont company until 2015, when The Chemours Company acquired the trademark. The first CFCs were synthesized by Belgian chemist Frederic Swarts, who created CF2Cl2, or Freon-12. By the late 1920s, American company General Motors formed a team of scientists to replace toxic chemicals such as ammonia, chloromethane, and sulfur dioxide. American scientist Thomas Midgley Jr., who also invented leaded petrol (which was used in many early automobiles), was a major proponent of CFCs. CFCs were popular because of its low boiling point, low toxicity, and non-reactive nature. Midgley’s team completed the development of CFC (Freon-12) in 1930.

World War II saw CFC use take off (literally and figuratively), with the chemicals being present in both military aircraft, and, after the war, civil aircraft as well. CFCs also found applications in fighting fires where water and dry-powder extinguishers could damage equipment such as in computer rooms, telecommunications equipment, laboratories, museums, and even warships. By 1973, James Lovelock,who invented the electron capture detector in 1957 (a device for detecting atoms and molecules in a gas through the attachment of electrons via electron capture ionization), used his invention to detect CFCs in the air. His findings led to the Montreal Protocol of 1987. By 1990, the agreement was revised to eliminate the use of CFCs by 2000, and elimination of CFCs from developing countries by 2010. The United States banned CFCs in aerosol cans in 1978, with DuPont originally opposing the plans to eliminate them, but by 1986 publicly condemned CFCs, even appearing at the initial Montreal Protocol to condemn CFCs themselves.

In its short history, CFCs have managed to make a huge negative impact on the environment, but efforts to close the hole in the ozone layer (which was actually at its widest in 2006) have been widely effective. According to recent reports, the hole in the ozone layer will completely close by the year 2050, which is good news for climate change scientists and environmentalists across the world.

Also published in Gadgets Magazine October Issue 2016

Words by Jose Alvarez