Oxybenzone

The Sun Safety Alliance (SSA), a nonprofit coalition, is preparing to inundate practitioners and the public with information about skin cancer prevention, according to the group's web site (www.sunsafetyalliance.org). The bulk of the advice focuses on the need to apply sunscreen "liberally" and "often." Although the group is supported by the American Academy of Dermatology, its members come from the commercial sector and include the National Association of Chain Drug Stores (NACDS), Schering-Plough HealthCare Products' Coppertone[R] sun care line, Roche Vitamins, and The Walt Disney Company's DisneyHand program. The information on the web site emphasizes the dangers of UV rays and ignores the benefits of sunlight's role in the creation of vitamin D, "the sunshine vitamin."

When exposed to UVB rays in sunlight, skin produces vitamin D. Skin production accounts for most of the body's supply. Vitamin D is involved in calcium absorption. Low blood levels of this vitamin are linked to an increased risk of breast and colon cancers. Scientists at an October 2003, National Institutes of Health conference, "Vitamin D and Health in the 21st Century," reported an 'alarming prevalence' of vitamin D deficiency in the US. Scientists attribute the deficiency partly to diet and partly to worries about UV rays and skin cancer that keep people indoors or coated with sunscreen.

Although much is made of the thinning ozone layer as a reason to wear sunscreen, some of the UV rays in sunlight are able--and have always been able--to pass through the ozone layer. The ozone layer primarily stops UVC rays, which have the shortest wavelength. UVB rays, which have a medium length, are only partially absorbed by the ozone layer. They do not penetrate the skin as deeply as the longer UVA rays do and are the primary cause of sunburn. While the body uses UVB rays to make vitamin D, too much of a good thing can cause tissue damage. The ozone layer does not stop UVA rays at all. UVA rays, which account for 90-95% of the ultraviolet light that reaches earth, are absorbed by melanocytes that cause the skin to tan. These rays can also weaken the skin's connective tissue and make it more susceptible to sun damage. In addition, UVA rays suppress immune function. Tanning beds use mostly UVA light sources. Melanoma has increased sharply, even in areas where no change has occurred in the ozone layer. Professor Johan Moan of the Norwegian Cancer Institute looked at the yearly incidence of melanoma in Norway from 1957 to 1984 and found a 350% increase among men and 440% increase among women during that period

Some researchers believe that the increased use of chemical sunscreens that absorb rather than reflect UV rays is the main cause for the rise in skin cancer. Oxybenzone, a principal ingredient in most sunscreens including Coppertone, absorbs UVA light and then is readily absorbed through the skin and excreted in the urine. Although Cameron Hayden and colleagues at the University of Queensland, Australia, who performed the research, do not know the long-term effects of sunscreen use, they are wary. (The Lancet, 9/20/97). In his article "Sunscreens: Do They Cause Skin Cancer?" Hans R. Larsen, MSc ChE, says that benzophenone derivatives, which include oxybenzone, are powerful free radical generators: "Benzophenone is activated by ultraviolet light. The absorbed energy breaks benzophenone's double bond to produce two free radical sites. The free radicals desperately look for a hydrogen atom to make them 'feel whole again.'" Larsen also notes that wherever chemical sunscreens are promoted, the incidence of melanoma rises. Part of the problem may be that sunscreens give people a false sense of safety and they stay out in the sun longer since their skin does not burn.

Rather than relying on frequent and liberal applications of absorbing sunscreens, consumers can use a reflecting physical sunscreen such as calamine lotion, based on zinc oxide, or wearing protective clothing and a wide-brimmed hat while outside. A moderate natural suntan also offers some protection. Hans Larsen says, "regular and moderate unprotected sun exposure in the early morning or late afternoon will help maintain a protective tan and keep your vitamin D stores at an optimum level."

The active ingredient in sunscreen: is it safe? (oxybenzone) Healthfacts, July 1998 www.findarticles.com/cf_dls/m0815/nf_v23/20963314/p1/article.jhtml

Federal Trade Commission. Indoor Tanning. http://my.webmd.com

Larsen, Hans R., MSc ChE. Sunscreens: Do They Cause Skin Cancer? International Journal of Alternative & Complementary Medicine, Vol 12, No 12, December 1994, pp. 17-19

Stephens, Anastasia. What the ingredients in sun cream can do to your health. www.taylorjackson.com/suncreams_that-damage.htm

Sunscreens--cancer in a bottle? The dangers of PABA/Oxybenzone. www.natural-health-information-centre.com/paba-oxybenzone.html

Toor, Daryl. American Academy of Dermatology Teams Up with Drug Stores and Coppertone[R] to Mislead Sun-Tanners about Health Benefits of Sunshine. Press release from Wolff Systems Technology, April 1. 2004

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