Ultraviolet Rays, often going just by the name UV rays, may at first sound as some very intriguing phenomenon. However, it is something we are exposed to or experience every day in our lives. Scientifically speaking, ultraviolet ray is a type of invisible ray that emanates from the sun in the form of energy. UV radiation lies beyond the violet end of the visible spectrum, having a wavelength range of 10-400 nanometers. This solar radiation does not possess a penetrating power as great as the X-rays, but it can penetrate the human skin up to a certain level. The ultraviolet rays can be split up in 3 types- the UVA, UVB and UVC rays. While most of the UVC rays are absorbed by the ozone layer in the earth’s atmosphere, the UVA and UVB rays do manage to reach us. Ultraviolet rays have both positive and negative effects on all living beings, some of which are elucidated below.
Positive effects of UV rays:
• While ultraviolet rays have the negative effects on our health, as stated above, they also prove to be beneficial in certain aspects of human health. UV rays are known to stimulate vitamin D in our body, which helps in vitalizing our bones and muscles and boosts our immune system. It may sound ironical, but UV rays also help in relieving certain symptoms of Psoriasis, a skin ailment, as well as Tuberculosis. It is also claimed that UV rays boosts the production of melatonin, which leads to reversal of Seasonal Affective Disorder, increases energy and helps in having a proper sleep schedule.
• UV rays have some industrial benefit as well, contributing considerably in the field of pest control. They are also used in testing insulation of certain electrical devices as well as in authenticating important documents such as passport.
• Ultraviolet light is very useful tool in disinfection and sterilization. They UV rays present in nature deactivate many harmful viruses and bacteria present in the air, by destroying their DNA.
• Because of its sterilizing properties, ultraviolet light also finds its use in water purification. UV rays are being extensively used in purifying water, as an alternative of chlorination of water. While one runs the risk of chlorine reacting with water in case of chlorination, the use of UV rays’ steers clears of such dangers.
• UV rays can also be said to be nature’s gift to animals. These rays help in the vision of birds and bees. They can recognize the UV light markings on flowers, that help them hunt for food.
Negative effects of UV rays:
• A lot of awareness has already been spread about the carcinogenic effects of ultraviolet rays. Being one of the most universal and prominent cause of cancer, ultraviolet rays are known to be responsible for 90% of the three most major skin cancers. Besides initiating this deadly disease, prolonged exposure to UV rays destroys the connective tissue and collagen present in the skin, which can lead to early aging of the skin, pigmentation and dark spots. A precaution against the above is to generously apply an SPF of at 30 and letting it absorb in your skin for a minimum 15 minutes before leaving the house.
• Not only do UV rays affect our skin, but can also be harmful to our overall health, by altering the function of white blood cells in our body, which results in a suppressed immune system for up to 24 hours after being exposed to the UV rays. They can also be harmful to our eye tissues, causing the development of conditions such as cataracts and pinguecula.
• Just the way ultraviolet rays alter the composition of our skin, they also affect the quality of synthetic material exposed to them. UV radiation is known to degrade items made with plastics like nylon and polystyrene, leading to a loss of strength in these materials. Therefore, it is advised not to consume water or food contained in plastic containers that have been exposed to the sun for long. Because certain pigments tend to absorb UV radiation, these notorious rays change and fade the color of hair, fabric and furniture.
Though ultraviolet rays have been around us ever since the planet came into being, the awareness about the effects of this radiation has started recently. This is because the ozone layer in our atmosphere is depleting, leading to the arrival of more UV rays on Earth than before. While UV rays have many positive effects on us, it is always wise to take precautions against the negative aspects of UV rays and stay safe.