<P> Since the late 1970s, the use of CFCs has been heavily regulated because of their destructive effects on the ozone layer . After the development of his electron capture detector, James Lovelock was the first to detect the widespread presence of CFCs in the air, finding a mole fraction of 60 ppt of CFC - 11 over Ireland . In a self - funded research expedition ending in 1973, Lovelock went on to measure CFC - 11 in both the Arctic and Antarctic, finding the presence of the gas in each of 50 air samples collected, and concluding that CFCs are not hazardous to the environment . The experiment did however provide the first useful data on the presence of CFCs in the atmosphere . The damage caused by CFCs was discovered by Sherry Rowland and Mario Molina who, after hearing a lecture on the subject of Lovelock's work, embarked on research resulting in the first publication suggesting the connection in 1974 . It turns out that 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 . Once in the stratosphere, the sun's ultraviolet radiation is strong enough to cause the homolytic cleavage of the C - Cl bond . </P> <P> 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 2 March 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 have been completely eliminated from developing countries as well . </P> <P> Because the only CFCs available to countries adhering to the treaty is from recycling, their prices have increased considerably . A worldwide end to production should also terminate the smuggling of this material . However, there are current CFC smuggling issues, as recognized by the United Nations Environmental Programme (UNEP) in a 2006 report titled "Illegal Trade in Ozone Depleting Substances". 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; as of 2007, China, India and South Korea were found to account for around 70% of global CFC production, South Korea later to ban CFC production in 2010 . Possible reasons for continued CFC smuggling were also examined: the report noted that many banned CFC producing products have long lifespans and continue to operate . The cost of replacing the equipment of these items is sometimes cheaper than outfitting them with a more ozone - friendly appliance . Additionally, CFC smuggling is not considered a significant issue, so the perceived penalties for smuggling are low . While the eventual phaseout of CFCs is likely, efforts are being taken to stem these current non-compliance problems . </P> <P> By the time of the Montreal Protocol, it was realised that deliberate and accidental discharges during system tests and maintenance accounted for substantially larger volumes than emergency discharges, and consequently halons were brought into the treaty, albeit with many exceptions . </P>

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