We all know the sun-safety mantra “slap on some sunscreen” . Yet for the same reason that organic food is in such demand, many people have concerns about the lotions' potentially harmful chemicals. There are products that boast they're free of toxic ingredients, but, like certain herbal supplements, just because something is labelled “natural”  doesn't necessarily mean it's safe or effective. With so many creams to choose from, it's no wonder consumers get confused.

Those wary of all things synthetic point to a study published in the American Journal of Public Health in April 1992. Titled “Could sunscreens increase melanoma risk?” , the report noted that the greatest increase in melanoma has occurred in countries like Australia, where the medical establishment has vigorously promoted the use of sunscreens.

Jason Rivers, a dermatology professor at UBC, however, says that the benefits of sunscreen far outweigh any possible risks.

As many as 20 percent of Canadians have an “irritant reaction”  to sunscreen, Rivers told the Straight, and fewer are actually allergic. A common allergen in commercial sunscreens is the chemical benzophenone, he said, which also goes by the names phenyl ketone, diphenyl ketone, or benzoylbenzene. Although it isn't clear how much of benzophenone is absorbed into the bloodstream, the substance has been found in urine samples of study participants. Nevertheless, he maintains that sunscreens are safe.

“There's no evidence these ingredients cause changes to cells or are carcinogenic in their own right,”  said Rivers, who's also a spokesperson for the Canadian Dermatology Association. “There's no evidence they have a negative effect on vitamin-D metabolism. There is evidence to support they prevent sunburn and reduce premature aging of the skin and the risk of certain cancers.” 

According to the Canadian Dermatology Association's Web site (www.dermatology.ca/), people allergic to or intolerant of chemicals should look for products that reflect the sun's rays (a sunblock) rather than absorb them and that contain nontoxic ingredients like titanium dioxide and zinc oxide.

Sounds easy enough. But some environmental groups argue that if those last two substances are nanosized, they could in themselves pose a health risk.

Nanotechnology involves the creation and manipulation of materials at the atomic and molecular level. Because of their minute dimensions, the particles could theoretically cross biological membranes and easily reach cells.

In a May 2006 report, “Nanomaterials, Sunscreens and Cosmetics: Small Ingredients, Big Risks” , Friends of the Earth Australia and Friends of the Earth United States claimed that several types of nanoparticles can be harmful to human tissue. But without mandatory product labelling, it's impossible to know which sunscreens contain them. The report stated that, according to the Australian Therapeutic Goods Administration, almost 400 commercially available sunscreens contain nanoparticle titanium dioxide or nanoparticle zinc oxide””but the TGA won't disclose which ones.

To protect consumers, the Friends of the Earth organizations are calling on federal governments around the world to withdraw sunscreens (as well as cosmetics and personal-care products) containing nanoparticles until peer-reviewed safety assessments have been done.

Meanwhile, it's up to consumers to make informed choices about how they protect themselves from the sun.

The Canadian Dermatology Association recommends using sunscreens with a minimum SPF of 15 to protect against the sun's ultraviolet-B rays, the ones that cause burns. Crucial is protection against ultraviolet-A rays, which deeply penetrate the skin and lead to premature aging and the development of skin cancers. Since people don't apply as much sunscreen as they should, Rivers said it's even better to get a sunscreen with an SPF of 30.

Sunscreens shouldn't be used as people's first line of defence against ultraviolet rays anyway, he added, reminding people to seek shade and cover up with clothing. And use a minimum SPF-15 lip balm to protect your pucker.

Barring nanonasties, here are a few natural sunblocks for folks who'd rather skip chemical substances altogether.

LAVERA FAMILY SUN SPRAY SPF 15 ($33.99 for 188 millilitres at Capers Community Markets [various locations]) Made with organic-jojoba and -calendula extract, this mineral-based, waterproof sunscreen has “broad-spectrum”  coverage, which means it protects against UVA, B, and C rays. It contains titanium dioxide with an aluminum coating; according to the manufacturer's Web site, mineral pigments create a physical shield that sits on the surface of the skin to block the sun's rays. Lavera claims you don't need to wait up to half an hour before it kicks in.

The founder of the Hanover, Germany–based Lavera Naturkosmetik, Thomas Haase, has dermatitis, so all of the line's products are allegedly suitable for sensitive skin and don't contain synthetic preservatives, additives, petroleum-based ingredients, emulsifiers, colours, or fragrances.

ALBA BOTANICA CHEMICAL-FREE SUNSCREEN SPF 18 ($9.99 for 188 millilitres at Whole Foods Market [The Village at Park Royal, West Vancouver]) Hypoallergenic, this lotion provides broad-spectrum coverage via titanium dioxide mixed with aloe vera, chamomile, ginkgo biloba, green-tea leaf, oat-kernel flour, and vitamins E and B5, among other ingredients that soothe the skin.

AUBREY'S GREEN TEA SUNBLOCK SPF 25 ($11.99 for 118 millilitres at Choices Markets [various locations]) Originally created for kids because of their sensitive skin, Aubrey's contains titanium dioxide and padimate O””a supposedly safer derivative of now rarely used para-aminobenzoic acid (PABA)””as well as green tea, willowherb, and vitamins C and E. According to a study published in the February 1999 issue of Photochemistry and Photobiology, the main polyphenolic constituent in green tea, epigallocatechin-3-gallate, might protect against UVB rays.

The Washington, DC–based Environmental Working Group, which alleges that some sunscreens contain hazardous or untested ingredients, is conducting a study on sunscreen safety and effectiveness. For details, go to www.ewg.org/questionnaire/sunscreen/.