Sun Protection

Excessive exposure to the sun’s UVB and UVA rays increases the risk of sunburns, premature aging, and skin cancer. Sunscreens and sun-protective clothing help to protect the skin of infants and children from these harmful effects.

Sun Protection

Why Sun Protection?

Sunny days are a good excuse to have some “fun in the sun.” A day at the beach, outdoor exercise, or a simple backyard gathering all result in skin sun exposure. Sunburns may occur, however, when this exposure is excessive or precautions are not taken. The more sensitive skin of infants and children is particularly at risk.

The Sun Story

The sun emits three different types of ultraviolet radiation: UVA, UVB and UVC rays. We are protected against UVC and most UVB rays by the earth’s ozone layer. Clouds, however, provide no protection. UVA rays easily penetrate both the ozone layer and the dermis of the skin. About 10 percent of UVB rays escape the ozone layer. They effect only the epidermis.

Environmental factors influence the amount of exposure. Daytime sun is most intense from 10:00am to 4:00pm. Sand, water, and snow all reflect ultraviolet rays, causing multi-directional skin exposure. UVB and UVA radiation is stronger in equatorial regions and at higher elevations.

Vitamin D and The Sun

There is some benefit to a limited amount of skin sun exposure. UVB radiation triggers a photosynthetic reaction that produces vitamin D3 within the dermis. It is then converted into 25-hydroxyvitamin D (25[OH]D which circulates throughout the body. A fraction of this conversion occurs within the skin, but it is mostly formed in the liver. How much vitamin D3 is produced varies with the amount of melanin present in the skin. Low melanin blocks less of the UVB rays, resulting in greater vitamin D3 production.

Vitamin D is important for a variety of body functions. It facilitates bone mineralization with calcium to prevent rickets and fractures. It also plays a role in the immune system via receptors on B cells, T cells, and other white blood cells. There is ongoing research to investigate its ability to prevent certain cancers, psoriasis, and cognitive disorders.

Too Much Sun is NOT a Good Thing

UVB rays are the primary cause of sunburns, but UVA rays cause more latent sunburn symptoms. Both types of radiation can damage skin cell DNA, resulting in premature skin aging and increasing the risk of skin cancer.

The three types of cancer caused by UVA and UVB sun rays are squamous cell, basal cell, and melanoma. The former two are found within the epidermis, and are usually very localized. Melanoma develops within the melanocytes of the dermis. Because of their proximity to blood vessels, this type of cancer can easily spread throughout the body, and is more difficult to treat.

In addition to effects on the skin, too much sun exposure is detrimental to the eyes. Because the cornea buffers the majority of ultraviolet radiation, keratitis or cataracts may develop, especially from UVB rays. Squamous intraepithelial carcinoma is also possible.

Recommendations for Sun Protection

The sun protection factor (SPF) refers to the amount of UV radiation that can cause a sunburn on protected versus unprotected skin. The higher the SPF number, the more protection provided. This number, however, does not represent the length of time that the skin is protected. The term SPF can be applied to a lotion, cream, or spray.

SPF topical skin products range from levels two to 100. There is disagreement regarding the true benefit of the highest SPF levels, but consensus that SPF 15 should be the minimum used. Sunscreens that are labeled “broad spectrum” protect against both UVA and UVB rays. They should be applied at least 15 to 30 minutes prior to sun exposure. All skin should be covered, avoiding the eyes and mouth. Most of these products “wash off” in water, so they must be re-applied every two hours when swimming.

Sunscreen sprays have gained popularity in recent years due to their ease of application. However, care must be taken to ensure that all skin surfaces are well sprayed. Sunburns can occur on areas missed during application, especially when used on a windy day. In addition, the aerosols in these products are often flammable. These sunscreens should not be used or worn near a fire pit, barbecue grill, or any object with a flame.

Sun protective hats and clothing are labeled by their UPF or ultraviolet protection factor. They are manufactured in a way that the sun cannot easily penetrate the fabric, and provide a UPF of 50 or greater. Although durability wanes over time with laundering, in most cases, the protective effect lasts two to three years. Sunscreen should still be used on exposed areas of skin.

– Infants –

The skin of infants is thinner than that of older children. It is, therefore, at a greater risk of sunburns. Limiting direct sun exposure is important, especially under the age of six months. Infants should be kept in shaded areas, and wear protective clothing. Infant-sized hats help to protect the face and eyes. Previously, sun creams and lotions were not recommended for infants under six months old. The AAP has since revised its policy. When sun exposure is avoidable, and shade or protective clothing are not possible, a small amount of sunscreen may be applied.

– Children –

Sunscreen is typically used at the pool or beach, but often forgotten prior to other outdoor activities. Exposed skin can sustain a sunburn even while skiing or snowboarding. Athletic team uniforms may not have sufficient UPF protection. For the eyes, most children over the age of three are able to wear sunglasses that protect against both UVA and UVB rays.

Concerns About Sunscreen Ingredients

Ingredients that block harmful sun rays when applied to the skin include the following:

-Aminobenzoic acid -Meradimate -Padimate O

-Avobenzone -Octocrylene -Ensulizole

-Cinoxate -Octinoxate -Sulisobenzone

-Dioxybenzone -Ostisalate -Titanium dioxide

-Homosalate -Oxybenzone -Trolamine salicylate

-4-Methylbenzylidene -Zinc oxide

Over the years, there has been increasing concern about the environmental effects of some of these ingredients. Oxybenzone, octocrylene, octinoxate, and ethylhexyl salicylate have been detected in water sources around the world. These chemicals are difficult to remove via conventional water treatment techniques. Oxybenzone, in particular, has been associated with the bleaching of coral reefs. Many localities have since banned the use of such sunscreens to protect marine life.

Mineral-based sunscreens offer an alternative to conventional ones. They involve combining a variety of mineral compounds to zinc oxide or titanium dioxide. The minerals then provide protection by repelling UVA and UVB rays. These options are ideal for infants and children with sensitive skin, and they are safe for the environment.

Artificial Tanning Devices

Unfortunately, sun lamps and tanning beds are popular among some teens. The UVA radiation emitted from these devices is 10 to 15 times greater than that of the midday sun. Initial skin reactions are similar to a typical sunburn. Repeated use and prolonged exposure increases the risk of developing all three types of skin cancer. Because of this risk, the World Health Organization, American Academy of Dermatology, and other health authorities support laws to ban the use of artificial tanning devices under the age of 18.

Treatment of Sunburns

In the unfortunate event of a sunburn, it is necessary to cool the skin as soon as possible. Getting into the shade, and applying cool water can reduce extent of the sunburn. Aloe vera gel further cools the skin, and soothes the irritation. Over-the-counter pain relievers such as ibuprofen and acetaminophen can reduce the intensity of the pain. Oral hydration is important to replace skin fluid losses, and correct dehydration following sun exposure. Burns associated with blisters or that cover a large body surface area may need professional medical attention. In these situations, topical antibiotic ointments may be prescribed to prevent infection, or silvadene to reduce the pain.