Writing in their latest update on UVA and UVB radiation in the International Journal of Cosmetics Science, the team from the University of Campinas say that radiation that can reach the skin indoors may cause rash and other types of blemish on the skin, meaning protection may be needed when inside too.
The research says that the effects of UVA and UVB radiation on organisms range from erythema formation, through tanning and reduced synthesis of macromolecules such as collagen and elastin, to carcinogenic DNA mutations.
Some studies suggest that, in addition to the radiation emitted by the sun, artificial sources of radiation, such as commercial lamps, can also generate small amounts of UVA and UVB radiation.
Depending on the source intensity and on the distance from the source, this radiation can be harmful to photosensitive individuals, says the new paper. However, in healthy subjects, it points out that the evidence on the danger of this radiation is still far from conclusive.
Every day the sun generates different types of radiation that can reach the Earth's surface, and the intensity of this radiation varies with latitude, altitude and the Earth's surface.
The effects of the radiation, mainly UVA and UVB, on organisms and structures, especially on human skin, are clear and well documented.
Effects such as sunburn, premature ageing and cancer are well distributed throughout the population, which requires using sunscreen products.
It is worth noting that UV radiation also has beneficial health effects, as it stimulates the production of vitamin D3, which is involved in bone metabolism and immune system functioning.
It is also used to treat skin diseases such as psoriasis and vitiligo, and regular exposure to UV radiation characterizes phototherapy, which can be used in combination with drugs that increase sensitivity to radiation, improving the symptoms of certain skin.
There is also evidence of the relationship between sun exposure, increased production of hormones and improved disposition and mood. Prolonged deprivation of sunlight, such as in countries of the far north during winter, can lead to seasonal order disorders.