How Does UV Radiation Affet My Skin? What Are the Risks? U V radiation, a known arinogen, an have a number of harmful effets on the skin. The two types of UV radiation that an affet the skin-uva and UVB-have both been linked to skin aner and a weakening of the immune system. They also ontribute to premature aging of the skin and atarats (a ondition that impairs eyesight), and ause skin olor hanges. Capillaries Flbrotlasts Lymphoytes Marophages Mast Cells Granuloyles Collagen, Vessels Elasti Fibers GAGs. Flbronetln UVA Rays UVA rays, whih are not absorbed by the ozone layer, penetrate deep into the skin and heavily ontribute to premature aging. Up to 90 perent of the visible skin hanges ommonly attributed to aging are aused by sun exposure.' UVB Rays These powerful rays, whih are partially absorbed by the ozone layer, mostly affet the surfae of the skin and are the primary ause of sunburn. Beause of the thinning of the ozone layer, the effets of UVB radiation will pose an inreased threat until the layer is restored in the latter half of the 21 " entury. Are Some People Predisposed to Adverse Health E E verybody, regardless of rae or ethniity, is subjet to the potential adverse effets of overexposure t o the sun. How ever, some people are more vulnerable than ot hers to the ha rmful effets of the sun. Skin Type Skin type affets the degree to whih some people burn and the t ime it takes them to burn. Th e Food and Drug Administrat ion (FDA) lassifies skin type on a sale f rom 1 to 6. Individuals w ith low er number ski n types (1 and 2) have fair skin and tend to burn rapidly and more severely. Individuals with higher number skin types (5 and 6), though apable of burning, have darker ski n and do not burn as easily.
How Do Sunsreens Work? What Is the Sun Protetion Fator {SPF)? S unsreens protet your skin by absorbing and/or refleting UVA and UVB rays. The FDA requires that all sunsreens ontain a Sun Protetion Fator (SPF) label. The SPF reveals the relative amount of sunburn protetion that a sunsreen an provide an average user (tested on skin types 1, 2, and 3) when orretly used. Sunsreens with an SPF of at least 15 are reommended. You should be aware that an SPF of 30 is not twie as protetive as an SPF of 15; rather, when properly used, an SPF of 15 protets the skin from 93 perent of UVB radiation, and an SPF 30 sunsreen provides 97 perent protetion (see hart to the right). SPF vs. UVB protetion 100 10 15 20 25 30 35.4() 45 50 55 60 65 SPF Although the SPF ratings found on sunsreen pakages apply mainly to UVB rays, many sunsreen manufaturers inlude ingredients that protet the skin from some UVA rays as well. These "broad-spetrum" sunsreens are highly reommended. ffets Resulting From Sun Exposure? The same people who are most likely to burn are also most vulnerable to skin aner. Studies have shown that individuals with large numbers of frekles and moles also have a higher risk of developing skin aner. Although people with higher-number skin types have a lower inidene of skin aner, they should still take ation to protet their skin and eyes from overexposure to the sun, sine ases of skin aner in people with darker skin are often not deteted until later stages when it is more dangerous. Additional fators Certain diseases, suh as lupus, an also make a person more sensitive to sun exposure. Some mediations, suh as antibiotis and antihistamines and even ertain herbal remedies, an ause extra sensitivity to the sun's rays. Disuss these issues with your physiian.
What Are the Ative Ingredients in Sunsreen? Chemial Ingredients Broad-spetrum sunsreens often ontain a number of hemial ingredients that absorb UVA and UVB radiation. Many sunsreens ontain UVA-absorbing avobenzone or a benzophenone (suh as dioxybenzone, oxybenzone, or sulisobenzone), in addition to UVB-absorbing hemial ingredients (some of whih also ontribute to UVA prot etion). In rare ases, hemial ingredients ause skin reations, inluding ane, burning, blisters, dryness, ithing, rash, redness, stinging, swelling, and tightening of the skin. Consult a physiian if these symptoms our. These reations are most ommonly assoiated w ith para-aminobenzoi aid (PABA)-based sunsreens and those ontaining benzophenones. Some sunsreens also ontain alohol, fragranes, or preservatives, and should be avoided if you have skin allergies. Physial Ingredients The physial ompounds t itanium dioxide and zin oxide reflet, satter, and absorb both UVA and UVB rays. These ingredients, produed through hemial proesses, do not typially ause allergi reations. Using new tehnology, the partile sizes of zin oxide and t itanium dioxide have been redued, making them more t ransparent without losing their ability to sreen UV. Summary All of t he previously mentioned hemial and physia l ingredient s have been approved by the FDA. The following table lists these ingredients and inludes information regarding the type and amount of ray protetion that they provide and their lass. FDA Monograph Amount of Chemial (C) Sunsreen Ingredients Ray Protetion or Physial (P) UVA UVB Aminobenzoi aid (PABA) 0 Avobenzone 0 Cinoxate 0 Dioxybenzone () Eamsule 0 Homosa lat e 0 Menth}'l ant hranilate () Otorylene ~ Otyl methoxyinnamate 0 Otyl saliylate 0 Oxybenzone () Pad imat e 0 0 Phenylbenzimidazole 0 Sulisobenzo ne () Titanium d ioxide () p Tro lamine saliylate 0 Zin Oxi de p Protetion Level: e =extensive () =onsiderable ~ = limited 0 = minimal For t he most up-to-date info rmation on approved su nsreen ingred ients, visit the FDA Web site at <www.fda.gov>. Can I Get a Tan Without UV? S unless tanners and bronzers are applied to the skin like a ream and an provide a temporary, artifiial tan. The only olor additive urrently approved by FDA for this purpose is dihydroxyaetone (DHA). Appliation an be diffiult, and areas of the skin an reat differently, resulting in an uneven appearane. Bronzers stain the skin temporarily, and they an generally be removed with soap and water. They may streak after appliation and an stain lothes. Sunless tanners and bronzers might not ontain ative sunsreen ingredients. Read their labels to find out if they provide any sun protetion.
How Can I Protet My Kids? Children Beause hildren w ill be exposed to UV radiation for their whole lives, it is important to engrain sun safety praties at an early age. Many parents do not properly apply sunsreen on their hildren. Sunsreen should be applied and reapplied to all exposed areas. Blistering sunburns during h ildhood signifiantly inrease the risk of developing skin ane r later in life. Between 1973 and 2003, utaneous melanoma inreased by 81 perent. 5 Inidene of pediatri melanoma is also on the rise- inreasing almost 3 perent per year- making it just as important to teah hildren SunWise behavior. 6 By teahing hildren about sun safety and enouraging them to take all of SunWise's sun safety ation steps, parents will ensure that their hildren understand the dangers assoiated with sun exposure and the ways to avoid them. Babies Keep babies out of diret sunlight. The Amerian Aademy of Pediatris reommends using sunsreen on infants for small areas suh as the fae and bak of hands where protetion from lothing is inadequate. 7 SunWise Program In response to the serious publi health threat raised by overexposure to UV radiation, EPA is working w ith shools and ommunities aross the nation through the SunWise Program. SunWise aims to teah hildren in elementary and middle shool and their aregivers how to protet themselves from overexposure to UV. For more information, go to the SunWise Web site at <www.epa.gov/sunwise>.
How Does the Outside Environment Influene Exposure? The intensity of the sun's UV rays reahing the Earth's surfae varies and should be onsidered when you plan outdoor ativities. The National Weather Servie issues the UV Index, a daily foreast of UV intensity, for the United States. The UV Index You an obtain your loal Index Number Exposure Level UV Index foreast daily.s. 2 Low from loal weather sta- 3 to 5 Moderate tions or newspapers. EPA's 6to 7 High Web site provides daily 8 to 10 Very High loal UV foreasts for 11+ Extreme your ZIP Code or ity and state at <www.epa.gov/ sunwise/uvindex.html>. The higher the UV Index foreast, the stronger the sun will be and the greater the need to follow all the sun protetion ation steps. For days when the UV Index is unseasonably high for a partiular loat ion, EPA issues a UV Alert. You an sign up to ree ive an email-based UV Alert or daily UV Index f oreast by going to <https://enviroflash.epa.gov> and entering your e-ma il address and ZIP Code or ity and state. In general, UV strength is greatest from 10 a.m. to 4 p.m. during sunny summer days. Up to 80 perent of UV rays pass through louds, however, meaning that sunburn is possible on loudy days as well. UV exposure is greater at low latitudes (nearer to the equator) and/or high altitudes. Snow, water, and sand also inrease sun exposure by refleting inoming UV rays, making it espeially important for skiers, boaters, and beahombers to wear lothing and hats and apply sunsreen. How Do I Apply Sunsreen? se a broad-spetrum sunsreen with an SPF rating of 15 or higher. Apply sunsreen 20 minutes before going out into the sun (or as direted by the manufaturer) to give it time to absorb into your skin. Apply it generously and regularlyabout 1 oune every 2 hours-and more often if you are swimming or perspiring. A small tube ontaining between 3 and 5 ounes of sunsreen might only be enough for one person during a day at the beah. Do not forget about lips, ears, feet, hands, ba ld spots and the bak of the nek. In addition, apply sunsreen to areas under bathing suit straps, neklaes, braelets, and sunglasses. Keep sunsreen until the expiration date or for no more than 3 years, beause the sunsreen ingredients might beome less effetive over time. Aording to the FDA, "water resistant" sunsreens must maintain their SPF after 40 minutes of water immersion, while "very water resistant" sunsreens must maintain their SPF after 80 minutes of water immersion. Either type of water-resistant sunsreen must be reapplied regularly, as heavy perspiration, water, and towel drying remove the sunsreen 's protetive layer. I Is Sunsreen Fail-Safe? sing sunsreen does not mean it is safe to spend more time in the sun, espeially when the UV Index is high. Although a sunsreen with an SPF of 15 or higher offers protetion from sunburn, it does not blok all of the sun's damaging rays. In fat, there is no evidene that sunsreens protet you from malignant melanoma, the deadliest form of skin aner, even though sunburns have been linked with the development of melanoma. There is only limited evidene that sunsreens protet you from several other types of skin aner. 9 To fully protet yourself, remember to seek shade, minimize peak hours of sun exposure, and wear protetive lothing in addition to applying sunsreen. J