The effect on the human body of ultraviolet radiation
The discovery of infrared radiation prompted the German physicist Johann Wilhelm Ritter to begin studying the opposite end of the spectrum adjacent to his violet region. It was soon discovered that radiation with very strong chemical activity was located there. New radiation has received the name of ultraviolet rays.
What is ultraviolet radiation? And what is its impact on earth processes and effects on living organisms?
The difference of ultraviolet radiation from infrared
Ultraviolet radiation, like infrared, is an electromagnetic wave. It is these radiations that limit the spectrum of visible light from two sides. Both kinds of rays are not perceived by the organs of sight. The differences in their properties caused by the difference in wavelength.
The range of ultraviolet radiation, located between the visible and X-ray radiation, is quite wide: from 10 to 380 micrometers (μm).
The main property of infrared radiation is its thermal effect, while the most important feature of ultraviolet is its chemical activity. It is thanks to this feature that ultraviolet radiation has a huge impact on the human body.
The effect of ultraviolet radiation on humans
The biological effect of different lengths of ultraviolet waves, has significant differences. Therefore, biologists have divided the entire UV range into 3 areas:
- UVA rays are near ultraviolet;
- UV-B - medium;
- UV C is the furthest.
The atmosphere enveloping our planet is a kind of shield protecting the Earth from a powerful stream of ultraviolet radiation coming from the Sun.
Moreover, UV-C rays are absorbed by ozone, oxygen, water vapor and carbon dioxide by almost 90%. Therefore, the Earth’s surface is mainly reached by radiation containing UV-A and a small fraction of UV-B.
The most aggressive is the shortwave radiation. The biological effect of short-wave UV radiation when exposed to living tissue could have a rather destructive effect. But fortunately, the ozone shield of the planet saves us from its impact. However, we should not forget that the sources of the rays of this particular range are UV lamps and welding machines.
The biological effect of long-wave UV-radiation consists mainly in erythemal (causing reddening of the skin) and tanning effect. These rays gently affect the skin and tissues. Although there is an individual dependence of the skin on exposure to UV.
Also, when exposed to intense ultraviolet eyes may suffer.
Everyone knows about the effect of ultraviolet radiation on humans. But mostly - this is superficial information. Let's try to cover this topic in more detail.
How does UV affect the skin (UV mutagenesis)
Chronic solar starvation leads to many negative consequences. In the same way as the other extreme - the desire to acquire a “beautiful, chocolate body color” due to a long stay in the scorching sun. How and why does UV affect the skin? What threatens uncontrolled sun exposure?
Naturally, reddening of the skin does not always lead to chocolate tan. Darkening of the skin occurs as a result of the body producing a coloring pigment - melanin, as evidence of the struggle of our body with the traumatic effect of the UV portion of solar radiation. At the same time, if redness is a temporary condition of the skin, then the loss of its elasticity, the growth of epithelial cells in the form of freckles and pigment spots is a lasting cosmetic defect. Ultraviolet, penetrating deep into the skin, can cause ultraviolet mutagenesis, that is, damage to skin cells at the gene level. Its most terrible complication is melanoma - a tumor of the skin. Metastasis of melanoma can be fatal.
Is there skin protection from UV radiation? To protect your skin from the sun, especially on the beach, just follow a few rules.
- Pastime in the open sun should be moderate and rational, light tan, obtained at certain hours, has photoprotective properties.
- Using sunscreen should be an integral part of your cosmetic program. When choosing a UV protector, make sure that it protects your skin from both the UV-A spectrum and UV-B.
- Use in your diet foods rich in antioxidants and vitamins C and E.
To protect the skin from ultraviolet radiation, you must use and specially selected clothing.
How does ultraviolet affect the eyes (electrophthalmia)
Another manifestation of the negative effects of ultraviolet radiation on the human body is electrophthalmia, that is, damage to the structures of the eye under the influence of intense ultraviolet radiation.
A striking factor in this process is the mid-wave range of ultraviolet waves.
This often happens under the following conditions:
- during the observation of solar processes without special devices;
- in bright, sunny weather at sea;
- while staying in a mountainous, snowy area;
- when quartzing rooms.
With electrophthalmia there is a burn of the cornea. Symptoms of such a lesion are:
- increased tearing;
- swelling of the corneal epithelium and eyelids.
Fortunately, usually the deep layers of the cornea are not affected, and after healing of the epithelium, vision is restored.
First aid for electrophthalmia
The symptoms described above can bring a person not only discomfort, but also real suffering. How to provide first aid for electrophthalmia?
The following actions will help:
- rinsing with clean water;
- burying moisturizing drops;
Compresses of wet bags of black tea and raw, grated potatoes perfectly relieve pain in the eyes.
If help did not work, consult a doctor. He will prescribe a cornea restoration therapy.
All these troubles could be avoided by using sunglasses with a special marking - UV 400, which will completely protect the eyes from all types of ultraviolet waves.
The use of ultraviolet radiation in medicine
In medicine, there is the term "ultraviolet starvation." This state of the body occurs when there is no or insufficient exposure to sunlight on the human body.
To avoid the pathologies arising at the same time, use artificial sources of UV radiation. Their metered use helps to cope with the winter deficiency of vitamin D in the body and improve immunity.
Along with this, ultraviolet therapy is widely used to treat joints, dermatological and allergic diseases.
UV exposure also helps:
- raise hemoglobin and lower sugar levels;
- improve thyroid function;
- restore the respiratory and endocrine systems;
- The disinfecting effect of UV rays is widely used for disinfecting premises and surgical instruments;
- Its bactericidal properties are very useful for the treatment of patients with severe, purulent wounds.
As with any serious impact on the human body, it is necessary to consider not only the benefits, but also the possible harm from ultraviolet radiation.
Contraindications for ultraviolet therapy are acute inflammatory and oncological diseases, bleeding, stage II and III hypertension, and active form of tuberculosis.
Each scientific discovery carries for mankind both potential hazards and great prospects for its use. The knowledge of the effects of ultraviolet exposure on the human body has made it possible not only to minimize its negative impact, but also to fully apply ultraviolet radiation in medicine and other areas of life.