Ozone is a poisonous gas with strong smell, and is a form of oxygen. It is pollutant when it exists between 5-10km above the earth's surface, causes breathing problems and harms the eyes. However, the ozone layer high above the earth, between 15-30km is not only useful, but absolutely necessary. And that's because it absorbs harmful radiation from the sun and thus protects earth and the life on it. If that solar radiation was to reach the earth, single-cell organisms would die, DNA would sustain dramatic changes and there would be multiplied symptoms of skin cancer.
Since 1970 there has been detected a reduction in the amount of ozone, creating an ozone hole over Antarctica in 1980. Thanks to research it was found that the cause of this reduction is chlorofluorocarbon. This chemical is a compound containing carbon fluorine and chlorine; it is a CFC that destroys the ozone layer. CFCs are used as cooling substances in refrigerators, air-conditions and in sprays. When they reach the ozone layer there is a reaction between these chemical elements, making the layer thinner and thinner.
In 1994 the European Council banned the creation of more CFCs, so as for other ozone-friendly substances to be used. Greenpeace in Britain made it to construct a fridge without CFCs, but it wasn't made as known as it should have been as it was against the interests of large industries. Until the day they will put their personal interests aside, the ozone layer will keep becoming thinner and thinner...
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