Ozone is formed from dioxygen by the action of ultraviolet light and broken down in the lower atmosphere. Trioxygen is a power oxidant, but it can damage mucous and respiratory tissues in animals, and also tissues in plants. It makes ozone hazardous inat the ground level, however, a higher concentration in the ozone layer is useful, because it prevents damaging ultraviolet radiation from getting into the Earth’s surface. The ozone which occurs in the stratosphere is being damaged by, for example, Freon. Freon is a registered trademark of The Chemours Company, which uses it for a number of halocarbon products. They are stable, nonflammable, moderately toxic gases or liquids which have typically been used as refrigerants and as aerosol propellants. These compounds are transported into the stratosphere by the windswind after being emitted from the surface. This damage is called ozone depletion (ozone hole). Ozone depletion is present in the total amount of ozone in Earth's atmosphere and a much larger springtime decrease in stratospheric ozone around Earth's polar regions. OzoneAn ozone hole transmits UV radiatonradiation that brings unwanted side effects, such as skin cancerscancer, strong sunburnssunburn and cataracts. But onOn other hand, there are positive effects, e.g. higher production of vitamin D. Other Another bad consequence of the ozone layer depletion is that UVB radiation causescausing the pyrimidine bases in the DNA molecule to form dimers, resulting in transcription errors when the DNA replicates. Furthermore, ozone acts as a greenhouse gas, absorbing some of the infrared energy emitted by the earthEarth. These holes also let in ozone and affectwhich affects cells within the plantplants. Mitochondria and chloroplasts are affected, preventing the plant to photosynthesiseplants from photosynthesising and respirerespiring effectively. The, causing plant leaves to develop spots, goturn brown, then the plant dies.