January 12, 2011

Sun Safety

 We just learned that a 12-year-old cruising buddy of Maia’s was diagnosed with melanoma (twelve!) something that I find both heartening and terrifying. It’s reassuring because it means the info is out there and people know what to be looking for. It’s scary because, well, it is. (Twelve!!)

If you’ve read this blog for a bit you’ll know I’m a bit obsessive about sun protection. The reason (beyond the fact we’re spending our lives in the tropical sun), is I was diagnosed with melanoma two years before we left--which, while scary for me, also means Maia has a higher probability of getting the disease.

Because of this I’ve spent quite a bit of time talking to cancer researchers and sellers of sun care products and have written far too many articles on the topic. But through all this we’ve worked out a system of sun protection we’re pretty happy with.

So this is what we do/suggest for other cruisers (and anyone, really):

--See a dermatologist for a complete check-up before you set sail. Our doctor walked us through my entire body and showed Evan and I what to watch for and which spots or moles to keep an eye on. Then follow-up annually as you travel. (I’m on a three-month check-up cycle).

--We made sure we had a good bimini/awning set-up that provides plenty of shade in the cockpit and fordeck (while at anchor). Side curtains also really help.

--We avoid the peak burning hours between 10-2. This dovetails nicely with home schooling and lunch inside the boat.

--When we do go out midday we tend to wear sun-protective clothing (either UV rash guards and board shorts for swimming, or long sleeved light-weight shirts like the type made by solumbra, as well as hats and good quality sunglasses (we’re amazed by how many sunglass-free cruising kids we see).

Then there is sunscreen, which is really a post in itself… For us sunscreen (our sunscreen of choice is Ombrelle with Mexoryl) goes on several times a day. But we really consider it the last line of defence. In part because of this:

The Food and Drug Administration’s 2007 draft sunscreen safety regulations say, “FDA is not aware of data demonstrating that sunscreen use alone helps prevent skin cancer” (FDA 2007). The International Agency for Research on Cancer agrees. IARC recommends clothing, hats and shade as primary barriers to UV radiation and writes that “sunscreens should not be the first choice for skin cancer prevention and should not be used as the sole agent for protection against the sun”

And there is the fact that there are stats that show higher skin cancer rates in sunscreen users. This is probably because people over-believe the hype and under use sunscreen. But it may also be that some sunscreen ingredients actually increase cancer growth.

But on with talking about sunscreen… At the risk of boring you with technical stuff, sunscreen needs to protect you against UVA and UVB rays. UVA is what is responsible for wrinkles, and aging. UVB is what causes your skin to darken and burn. While there is conflicting info on the topic, but generally:
UVB (burning) has a wavelength range (in nanometers) of:   
280-320
UVA (aging) has a wavelength range (in nanometers) of:      
320-400

So to protect yourself from the sun you need a sunscreen to contain ingredients that cover as wide a range as possible in the 280-400 spectrum. Here’s how a few of the most common sunscreen ingredients shape-up:

Zinc Oxide 290-380
Mexoryl 290-400
Avobenzene 340-375
Titanium Dioxide 290-340
Octinoxate and Octisalate 280-320
Oxybenzone 320-240

Many sunscreens combine ingredients to cover a wider range of the spectrum. But Zinc Oxide and Mexoryl cover the widest spectrum all by themselves, and they are photo-stable ingredients. This is extremely important, because it means your sunscreen won’t lose effectiveness an hour after you apply it like Avobenzene, for example, which is not photo-stable.

Then there are the issues with sunscreen chemicals themselves. Recently the FDA began investigating a type of vitamin A called retinyl palmitate, which is found in 41 percent of sunscreens. The FDA is investigating whether this compound may accelerate skin damage and elevate skin cancer risk when applied to skin exposed to sunlight—a detail which strikes me as less than awesome… Another well-known problem ingredient is oxybenzone, a hormone-disrupting compound found in about 60 percent of sunscreens…

So it comes down to this: The ideal sunscreen would effectively and comfortably block the UV rays that cause sunburn, immune suppression and damaging free radicals. But there is pretty much nothing that does that. The choice tends to be between “chemical” sunscreens, which are less stable and penetrate the skin, potentially disrupting the body’s hormone systems, or “mineral” sunscreens (zinc and titanium), which often contain micronized- or nano-scale particles of those minerals and can feel sticky on the skin and leave you with a white glow.

In the US they are particularly unfortunate. Two of the best sunscreen ingredients Mexoryl SX (ecamsule) and Tinosorb S and M are either extremely expensive or not yet available. And as far as the SPF level goes—we agree with the researchers that it’s a bunch of bunk—and simply by 30 SPF and reapply frequently.

For more guidance on choosing a sunscreen I love the sunscreen guide at the Environmental Working Group.
But what ever you choose, don’t forget to get a good hat.

6 comments:

Anonymous said...

I read the EWG stuff last spring and our family switched sun screens. The days of getting a good tan are over for our family.

Andy
Mpls, MN

Del Viento said...

Thanks! What service! Yeah, the EWG is what Windy's been reading. I agree with your approach to limiting the need for sunscreen in the first place. Besides, that Mexoryl will bust any cruiser's budget, so better to limit the amount of exposed skin that needs it. Michael

Diane, Evan and Maia said...

Michael--if you know someone coming down from Canada Mexoryl has been an ingredient up there for much longer and is not crazy expensive. The Ombrelle we buy- we get onsale for around $10 for a large container...

Steve and Lulu said...

Thanks for a very readable approach to the whole sunscreen issue. It can all get SO confusing. You've done a great job if distilling it down. Thanks again.
-Steve

Behan said...

Awesome post, Diane. It does get really confusing and it is so, so, so important for us. I too heart the EWG and their database! You have me more than a little freaked about the 12 y.o. with melanoma, though... more info please. Have you seen Alma yet?

We have really loved using the Blue Lizard sensitive skin sunscreen, and being able to purchase it in gallons made it pretty affordable. But you are right on about the tint that zinc & titanium based sunscreens leave... it fades, mostly, but still leaves a very heavy feeling. I'm looking for something lighter I can wear to work (ACK) without feeling ghostly. Suddenly appearance matters a little more... gah!

Diane, Evan and Maia said...

Hey Behan--they think it was just chance. The family are good at suncare, have no history... But melanoma is showing up at younger ages and it is lniked to sunscreen use--so who knows...
When you find that perfect sunscreen let me know:) I like Mexoryl--but it does have the pore clogging issue. Sigh.