Sail Naked? In regard to your article "Sunscreen Stripe-off" in the June 2007
issue: Blocking UVB blocks the formation of Vitamin D, our most important
defense against cancer. My wife and I observed a few years ago that we were no
longer getting sunburned and were easily developing a healthy—yes, healthy—tan.
After lots of research, we attributed this to the Omega-3 supplements we were
taking, and our avoiding Omega-6 fats. Alan Donaldson We’ve gotten a lot of interesting responses to our sunblock
test, including a correction from a chemist pointing out that our description of
potions that rely on physical blockers as sunscreens "don’t have any chemicals"
was inaccurate. UVB radiation does indeed enable the skin to synthesize the
"sunshine vitamin," Vitamin D, which is credited with many health benefits. As
far as we know, there have yet to be any long-term, double-blind studies
supporting the role Vitamin D plays in preventing cancer, but according to
Edward Giovannucci, an associate professor of medicine at Harvard University who
directed a Vitamin D study
Mac 26S and Sea Pearl Tri 21
Idaho Falls, Idaho
In regard to your article "Sunscreen Stripe-off" in the June 2007 issue: Blocking UVB blocks the formation of Vitamin D, our most important defense against cancer. My wife and I observed a few years ago that we were no longer getting sunburned and were easily developing a healthy—yes, healthy—tan. After lots of research, we attributed this to the Omega-3 supplements we were taking, and our avoiding Omega-6 fats.
We’ve gotten a lot of interesting responses to our sunblock test, including a correction from a chemist pointing out that our description of potions that rely on physical blockers as sunscreens "don’t have any chemicals" was inaccurate.
UVB radiation does indeed enable the skin to synthesize the "sunshine vitamin," Vitamin D, which is credited with many health benefits. As far as we know, there have yet to be any long-term, double-blind studies supporting the role Vitamin D plays in preventing cancer, but according to Edward Giovannucci, an associate professor of medicine at Harvard University who directed a Vitamin D study(http://www.harvardmagazine.com/) , just 20 minutes on a sunny beach can yield five times what he proposes is a healthy amount of Vitamin D.
A University of California Davis study indicates that UVA waves can break down sunscreen ingredients that are absorbed into the skin and turn them into cancer-causing agents.(http://www.sciencedaily.com/) One of the three potentially harmful ingredients is octocrylene (found in some of the products you recommended), and this must be encapsulated to prevent it from breaking down into potentially damaging free oxygen radicals (FOR). According to the study, micronized or micro-encapsulated titanium oxide or zinc oxide are needed to prevent the breakdown.
The U.S. Food and Drug Administration just approved L’Oreal’s Anthelios SX, which contains mexoryl and the encapsulators. (My wife and I recommend Blue Lizard SPF 30 Sport, Sundurance XT, and Proderma Competition Grade Prism SPF 50 or 45.)
None of the products we tested contained mexoryl—a photo-stable organic sunblock that was patented in Europe in 1982 and recently approved by the FDA—but several use the encapsulators. One of these was our Best Choice, Coppertone Spectra 3, which unfortunately has since been discontinued. From our understanding of the UC Davis study, frequent application of sunscreens with the encapsulators should prevent the formation of FOR. Given the editor’s eccentric skepticism toward most pharmaceutical studies, protective clothing remains his preferred first line of defense. (Staying out of the sun is unlikely in this line of work). As it happens,Practical Sailor is in the midst of testing hats, and are beginning a project to test UV-blocking clothes. In the meantime, we’ll grab a tube of the highly publicized L’Oreal goop and see how it does.
What About Lanocote?
Great article on anti-corrosives (April 2007). I just bought Lanocote spray and paste. It came highly recommended by a rigger.
We’ve got it and are doing a followup. The editor has used a similar New Zealand-made product on his galvanized turnbuckles and rigging with good results.
nufinish for boats
Please add another product to your study of non-marine waxes (March 2007 issue). I am a Gemini broker, and my detailer has been using NUFINISH for three years with great results. It goes on easy, comes off easy, and lasts about six months. He mixes it with a fine rubbing compound to clean the metal.
NavPak Pro Software?
I am looking at navigation software and read your review (September 2006) on this subject. I have examined Fugawi’s demo program that you listed. I have also found software from Global Navigation Software Co., specifically NavPak Pro. Have you reviewed this software?
Mike Slinn, who evaluated navigation software last year ("Software Wars," September 2006) and tested Nobeltec’s Admiral 9.1 for this issue (page 32), will be reporting on the NavPak software as soon as he fixes the head on his Beneteau First. In the meantime, you can check out Slinn’s blog at(www.marnav.info).
Beware in The Bahamas
This letter is a friendly warning to those who charter in the Bahamas. Not having had damage to a sailboat in a half-century of sailing, I elected to not take the insurance policy offered by The Moorings to charter a 38-foot catamaran at Marsh Harbour, Abacos. It was a costly mistake.
Shore areas were not well marked. Warnings of underwater rocks, destroyed six months before in a hurricane, had not been restored.
A long story short: I damaged a strut that took two days to fix ($2,500). Added to that were 14 laydays ($752) for a total of $3,252. It was an expensive lesson.
John E. Sonneland
I have a simple safety tether system on my Outremer 45 catamaran that might bear looking at: I have permanently installed port and starboard tethers which live on the jacklines by means of a sewn loop. They get me from the cockpit to the forestay, with enough slack to work at the mast but not enough to go through the lifelines. They are strong and failsafe, but best of all, they are silent: no dragging a piece of hardware forward along the deck, which is guaranteed to wake up the off-watch spouse. The only downside is not being able to go forward on one side and return on the other, but I never do that. I keep a short tether doubled on my harness if I need to move out of reach of the jackline.
Block Island, R.I.
Tether Issue Heats Up
I am writing in regard to the photo of Skip Allan wearing a safety tether doubled over the jackline (April 2007, page 20). As a rock climber for over 20 years, I have learned this is a very unsafe practice. Webbing-on-webbing or line under tension can melt in a very short distance. That is why climbers always use carabiners to separate webbing and line. ThePractical Sailor tester may not have ever experienced melting because he had not had enough force between the two webbings. But if he goes for a ride down a wet deck because of a wave, he could discover his tether melted as he goes overboard.
Please correct this unsafe advice, possibly by doing some testing, like figuring out the effect of a section of webbing running down a 40-foot jackline under tension.
A melting tether is indeed a possibility, but it seems pretty unlikely during use on a boat. The biggest concern would be if the wearer, even on a short tether, still managed to go over and was dragged long enough for the tether to break due to friction. The doubled-over tether arrangement used by Skip Allan for our test is not meant to be used full time, or when moving around on the deck, but at fixed stations where the tether’s full length puts the wearer at greater risk of being hurled or falling overboard. A short tether or two-leg tether would be better, but many sailors don’t like them because they can be cumbersome to wear.
You have requested information on experiences with Wi-Fi when cruising. We have been cruising the East Caribbean (British Virgin Islands to Grenada) for several winter seasons and have recently found Wi-Fi readily available (often free) in most marinas and many anchorages. However, we have found the use of an external antenna system far superior to the Wi-Fi cards available for most laptops. We use a 200mw EUB-362(EXT) made by Engenius. It is a very compact device that connects to our laptop with a USB cable. We upgraded from the standard 2db antenna to the optional 5db antenna. We have little trouble accessing Wi-Fi services with this arrangement, and the antenna is small enough to be readily portable. A marine kit with a permanent mount 8.5db external antenna is also available from(http://www.netgate.com/).
Readers planning to sail the East Caribbean might also be interested to learn that GSM cell phone service with data capability is available virtually everywhere. Data rates are currently about the same as dial-up, but it is fine for e-mail.
A GSM quad-band phone is required with a cable or blue-tooth connection to the computer. A word of caution: Before signing up for data minutes packages, determine if those minutes can be used internationally. In the case of Cingular (now AT&T), they cannot. Charges are 2 cents per KB internationally.