Although the sun is an energy source that all living creatures in the world need, it contains harmful effects that can cause many important problems, if care is not taken. Since we live in a country where the number of sunny days is above the world average, it is essential that we are more conscious about the positive or negative effects of sun rays on human health.
A Strange Concept for Many of Us: Ultraviolet Radiation!
As we know, the sun energizes a wide spectrum of wavelengths. Ultraviolet radiation with a shorter wavelength than visible blue or purple light is largely absorbed by the ozone layer in the stratosphere. However, some of this radiation reaches the earth, causing sunburn (and other negative effects on human health). Scientists divide ultraviolet radiation into three types: UV-A, UV-B and UV-C. Of these, UV-C has the shortest wavelength (100 – 280 Sunlight and Effect on Our Health nanometer) and cannot reach the earth because it is completely absorbed by the ozone layer, so we cannot talk about the harmful effects of UV-C rays for our body. Although UV-B, some of which is absorbed by the ozone layer (with a wavelength of 280 – 320 nanometers) does not affect the layers of the human skin as much as UV-A, it has been proven by scientific studies that it causes sunburn, darkening from the sun, DNA mutations and skin cancer. UV-A radiation is the radiation that poses the greatest danger for human health among ultraviolet radiation. (wavelength 320 – 400 nanometers) UV-A radiation acts on the bottom layer of the skin and plays a role in sunburn and darkening. It is also one of the known damages of UV-A, which disrupts the structure of the skin and causes wrinkles and sagging. Perhaps the most serious effect of UV-A is that it causes skin cancer. In addition, suppressing the immune system and permanently damaging the eyes are other harmful effects.
Ultraviolet Radiation Levels are Variable!
We know that the ozone layer absorbs ultraviolet radiation to a great extent and prevents it from reaching the earth. However, ozone levels vary throughout the day and year. It is a well-known fact that the ozone layer thins due to the gases that break down the ozone gas in certain parts of the world. The higher the sun in the sky, the higher the level of ultraviolet radiation. In other words, ultraviolet radiation varies during the day and year. It reaches its peak in the regions outside the tropical belt during the summer months and in the middle of the day when the sun is highest. As you get closer to the equator, the level of ultraviolet radiation increases.
Ultraviolet radiation can be reflected and scattered by different surfaces in different proportions. For example, fresh snow can reflect ultraviolet radiation up to 80%, dry sands on the beach up to 15% and 25% on the sea. Ultraviolet radiation reaches 40% of the surface even half a meter below the sea. Even in cloudy weather, ultraviolet radiation levels can be high. For example, more than 90% of this radiation can cross a light cloud cover. On a cloudy summer day, we can burn from the sun, even though the weather is not very hot. The scattering of the rays also acts like reflection from different surfaces and leads to an increase in the total ultraviolet radiation level.
Sun and Our Health
The relationship of the sun to health problems such as skin cancer and premature skin aging has been scientifically proven today, leaving no room for scientific suspicion. According to the data of the World Health Organization (WHO), there are three million melanoma (benign) cases and approximately 132,000 cases of malignant melanoma skin cancer worldwide. One of every three cancer cases diagnosed worldwide is skin cancer. In addition, in 20% of patients with cataracts, the most important factor in the emergence of the disease was determined to be exposure to the sun.
The most commonly known effect of excessive exposure to ultraviolet radiation is redness, also called sunburn. Depending on the skin type, the skin’s burn threshold and ability to adapt to ultraviolet radiation varies from person to person. Prolonged exposure to ultraviolet radiation leads to disruption in cells, fibrous tissues and blood vessels in the skin. Ultraviolet radiation accelerates skin aging, wrinkles occur as a result of the skin losing its elasticity, and the skin becomes thicker.
False Facts About Solar Radiations
False — Tanning provides protection from the harmful effect of the sun.
True– Tanning of a light-skinned person provides protection as much as a sunscreen with 4 protection factors.
False– It is not possible to burn from the sun on a cloudy day.
True– 90% of ultraviolet radiation coming from the Sun can pass through a thin layer of cloud. Fog in the atmosphere can lead to increased levels of ultraviolet radiation.
False– ultraviolet radiation in winter is not dangerous.
True– ultraviolet radiation levels are generally lower in winter than in summer. However, reflection from the snow causes the amount of ultraviolet radiation to double, especially at high altitudes. It is especially necessary to be careful in the spring, when the air temperatures are low, but the rays from the sun are strong.
False — “Since the sunscreen cream protects me, I can stay in the sun for a long time.”
True– sunscreen lotions should not be used to stay in the sun longer, but for protection when inevitably exposed to the sun.
False — If you take a regular break while sunbathing, there will be no sunburn.
True– It is important how long the total exposure to ultraviolet radiation is during the day; The total damage of ultraviolet radiation does not change, even if exposed at intervals.
False — If we do not feel the heat of the sun rays, we will not be burned by the sun.
True– Sunburn causes ultraviolet radiation and ultraviolet radiation does not cause warming. The feeling of warming depends on the infrared ray from the sun, not from ultraviolet ray.