Safety of Sunscreen
The sun’s rays have powered life on our planet since its creation, and have made life possible for all living things. The sun is one of the most important elements of the universe, but in recent years has only been condemned for some of its harmful effects on humans. Lately, all that is heard about the sun anymore is how can be harmful and how protection from overexposure is needed. Many people are scared of dangerous overexposure effects such as sunburn, premature aging of the skin, eye damage, and skin cancer. These fears cause many to try anything to avoid the sun including lathering themselves up with sunscreen. What many people do not realize is that as they slather on sun lotion for protection, they could actually be harming their skin. Overuse of sunscreen and sun block, which contain many potentially dangerous chemicals, could be even more harmful than exposure to the sun’s rays. Sunlight is produced through nuclear reactions in the sun’s core. Originally born as energetic gamma rays, after billions of collisions with matter, this radiation reaches the surface and escapes into space (Mitalas). The sun radiates light to the earth, and part of that light consists of ultraviolet (UV) rays. When these rays reach the skin, they can cause tanning or burning. There are three types of UV rays: UVA rays, which have the least amount of energy per photon, UVB rays, and UVC rays, which have the most amount of energy per photon. UVA rays pass through the ozone layer and make up the majority of sun exposure. UVB rays are mostly absorbed by the ozone layer, but can still pass through to the skin. UVC rays are the most dangerous, but these are blocked by the ozone layer and do not reach the earth.
Human skin contains natural protection against UV exposure. UV rays react with the melanin in skin. The presence of melanin is skin’s first defense against the sun because it absorbs UV rays before they do any damage. The lighter a person’s natural skin color, the less melanin it has for the absorption of UV and protection against sunburn. The darker a person’s natural skin color, the more melanin it has to protect itself. As the melanin increases in response to sun exposure, the skin tans. Sunburn develops when the amount of UV exposure is greater than what can be protected against by the skin’s melanin. Overexposure to the sun can have harmful effects. Many dermatologists believe there may be a link between childhood sunburns and melanoma later in life, but this is yet to be proven. Melanoma is a cancer that begins in the melanocytes, which are cells located in the bottom layer of the skin’s epidermis. Non-melanoma skin cancers are less deadly than melanoma skin cancers. The most common non-melanoma skin cancers are basal and squamous cell carcinomas, which are benign and are easily cured by simple outpatient surgery. Other UV-related skin disorders include actinic keratoses and premature aging of the skin. Actinic keratoses are skin growths that occur on body areas overexposed to the sun (SunWise). Chronic exposure to the sun also causes premature aging, and over time can cause skin to become thick, wrinkled, and leathery. Dermatologists suggest several methods to avoid experiencing these harmful effects. The most obvious is to just stay out of the sun. This is almost impossible to do, and could be dangerous because skin needs the vitamin D from sunlight. Mostly dermatologists suggest wearing products with SPF, such as sunscreens and sun blocks. The SPF in sun-care products is the “sun protection factor” which protects from sunburn-causing UVB radiation (Helmenstine). The SPF number represents how long someone can stay in the sun without getting sunburned. This rating is calculated by comparing the amount of time needed to produce sunburn on protected skin to the amount of time needed to cause sunburn on unprotected skin (Medmd). For instance, if a fair-skinned person who would normally turn red after 10...
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