The Sun is a gift that illuminates us every morning bringing heat and energy, but this star also emits energy outside the range we call visible light, that is, it is not perceived by our eyes. The band above visible light is called infrared and the band below it is called ultraviolet.
Irradiations with shorter wavelengths contain more concentrated energy, therefore, much stronger, these radiations correspond to the ultraviolet rays that are harmful to our health.
But nature in its perfection protects planet Earth with a shield against ultraviolet radiation, or rather, protected. The ozone layer is responsible for absorbing much of the harmful radiation before it arrives to the soil, but unfortunately the layer is being destroyed by pollutants such as CFC's (chlorofluorocarbons).
Ultraviolet rays (UV-B), with a wavelength between 290 and 320 nanometers, are more harmful to humans, they are called biologically active radiation. Most of this radiation is absorbed by the ozone layer, but a small portion that reaches the surface is already enough to harm human health.
If a person is exposed to UV-B radiation for longer periods, they may notice the appearance of sunburn on the skin which can lead to skin cancer. The US Environmental Protection Agency estimates that 1% ozone depletion causes a 5% increase in the number of people who get skin cancer. A study carried out in Brazil and the United States showed that a 1% reduction in the ozone layer caused a 2.5% increase in the incidence of melanomas.
By Líria Alves
Graduated in Chemistry
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Catalytic reactions and CFC's
Source: Brazil School - https://brasilescola.uol.com.br/quimica/consequencias-destruicao-camada-ozonio.htm
