UV Radiation Protection

UV Protection

UV Radiation and Protection

I need a cheat sheet to remember the facts about the sun’s ultra-violet (“UV”) radiation.

You can’t see UV because its wavelengths are shorter than the wavelengths the human eye can see without some special help. That makes it hard to believe it’s there and harder yet to remember that something we can’t see can hurt us. And like all science, there’s constantly new information about ultra-violet radiation, the damage it causes and what to do for protection. And what about climate change? What’s that going to do? Arghhhhhh. Let’s take it one step at a time.

The UV radiation from the sun is right now recognized as 3 wavelengths: UVA, UVB and UVC. UVA is the longest wavelength of the three and it is divided into UVA I and UVA Iii, with the UVA I being a little longer than UVA II. It seems that the longer the UV wavelength, the more troublesome it is. It is thought that UVC is absorbed by the ozone layer and very little if any reaches us on the earth.

So that leaves UVA and UVB to worry about.

They do penetrate the earth’s atmosphere and are a factor in premature skin aging, eye damage (including cataracts), and skin cancers. There are also indications that they reduce your immune system’s ability to fight disease. Yikes!

Excessive UV radiation can cause genetic mutations which can begin skin cancer. My dermatologist told me that my basal cell carcinoma could have been caused by a single sun burn.

Now the U.S. Department of Health and Human Services and the World Health Organization have identified UV as a proven human carcinogen. It is known that those rays are major cause of basal cell carcinoma and squamous cell carcinoma, the ones that plague me, my father and millions of other Americans. As for the deadliest skin cancer, melanoma, it is very possible that, especially for fair-skinned people like me, that UV radiation often plays a key role.

UVA rays are the primary “tanning ray” and they reaches our bodies during all daylight hours, passing through glass and clouds and many clothing materials. We get lots of UVA exposure during out lives. UVA rays are not as intense as UVB rays but they hitting our bodies during every daylight hour.

UVA rays pentrate the skin more deeply than do UVB rays and scientists believe they are primary factor in skin aging and wrinkling (photoaging). UVA contributes to and may even initiate the development of skin cancers.

It seems clear that that tanning, whether outdoors or in a salon, causes cumulative damage to our skin A tan actually means that there has been damage to the skin’s DNA; the skin grows darker to attempt to prevent further DNA damage or mutation. These imperfections, or mutations, can lead to skin cancer. The evidence indicates that tanning in a salon (which rely heavily on UVA rays) is even more dangerous than tanning in natural sunlight. Obviously, I avoid both religiously.

UVB rays don’t reach as deep as the UVA rays but they are largely responsible for the reddening of the skin and for the pain of sunburn. They damage the layers of the skin that are more near the surface. Like UVA rays, UBV rays play a key role in the development of skin cancer and a contributory role in tanning and photoaging.

Our exposure to UVB rays is not a pervasive as to UVA rays. UVB ray intensity varies by season, location, and time of day. This is the ray that you’re avoiding when you follow the almost common wisdom to stay out of the sun in the US between 10 AM and 4 PM from April to October. Keep in mind, though that, UVB rays can burn and damage your skin year-round, especially at high altitudes and on reflective surfaces. Luckily, UVB rays do not significantly penetrate glass.

There are lots of aspects to good comprehensive sun protection and their combination and use is a very individual pursuit that evolves over time but let’s start with the basics of “Sun Protection Factor (“SPF”) and sunscreens. An SPF is actually a relative term and it tells you how long it will take for UVB rays to redden skin when using a sunscreen, compared to how long skin would take to redden without the product. For instance, someone using a sunscreen with an SPF of 15 will take 15 times longer to redden than without the sunscreen. An SPF 15 sunscreen screens 93 percent of the sun’s UVB rays; SPF 30 protects against 97 percent; and SPF 50, 98 percent.

It seems pretty clear that all experts believe that SPFs of 15 or higher are necessary for adequate protection. However, I don’t trust SPF 15 for my very fair skin and I certainly never trusted it for my son. I look for a SPF of 30 or above in cosmetics and I always use a sunscreen of SPF 50 or higher.

Notice that the SPF only applies to UVB rays. SPF doesn’t tell you a thing about protection from UVA rays. SPF has been around since the late 1970s when the dangerous of UVA rays were not as widely recognized. So what about UVA ray sunscreen protection?

This is not as easy as looking at the SPF rating but you want some combination of the following UVA-screening ingredients: stabilized avobenzone, ecamsule (often listed as Mexoryl™), oxybenzone, titanium dioxide, and zinc oxide. Screens may also that they have UVA/UVB protection or use the phrase “multi spectrum,” “broad spectrum” or “UVA/UVB protection” on their labels. These all may be intended to indicate that some UVA protection is provided but it’s best to check the ingredients as well.

The Federal Food and Drug Administration (“FDA”) offers the following information:

The Skin Cancer Foundation (www.skincancer.org), a foundation devoted to educating the public and the medical profession about skin cancer, its prevention by means of sun protection, and the need for early detection and prompt, effective treatment, provides the following general sun protection advice.

• Seek the shade, especially between 10 A.M. and 4 P.M.
• Do not burn.
• Avoid tanning and UV tanning booths.
• Use a sunscreen with an SPF of 15 or higher every day.
• Apply 1 ounce (2 tablespoons) of sunscreen to your entire body 30 minutes before going outside. Reapply every two hours.
• Cover up with clothing, including a broad-brimmed hat and UV-blocking sunglasses.
• Keep newborns out of the sun. Sunscreens should be used on babies over the age of six months.
• Examine your skin head-to-toe every month.
• See your physician every year for a professional skin exam.

[Permission to reproduce the above information from the Skin Cancer Foundation and, in the future a direct link to their site, is being sought from the Foundation.]

This will get us started. There will be lots more to come!