Faithful followers of The Non-Toxic Times will recall that in our June edition we launched the summer season with a discussion of the many sunscreen ingredients available to consumers. Our article generated its fair share of reader mail, including a letter from one reader telling us we missed one of the most promising sunscreens around: Mexoryl, a new ingredient that works without the hazards presented by other compounds. We looked into it and were sufficiently impressed to offer this addendum on banishing the burn.

Given all the research that goes into a typical edition of The Non-Toxic Times, it came as no small surprise to receive a letter from a reader saying that our sunscreen article overlooked an ingredient that holds the promise to protect us from the sun without the toxicological problems of traditional sunscreen chemicals.

Could this be? Is it so? Was it missed? In a word, yes. And though we’re still not quite sure how we managed not to mention Mexoryl, we suspect the reason has to do with its chief caveat: It’s not legally available for sale in the United States because the Food and Drug Administration, which bears responsibility for approving the active ingredients in products like sunscreens, has yet to okay Mexoryl for use in this country.

Is the FDA’s refusal to approve Mexoryl evidence that the ingredient is unsafe? We don’t think so. In our hunt for literature about Mexoryl, we found a lot of suspicion that the agency’s motivation in this case is political. And our research seemed to back up this supposition. We discovered that Mexoryl not only appears to be safe, it’s also more effective than other sunscreening chemicals. Given its clean track record in other countries and its clearly superior efficacy, there’s almost no other conclusion to draw, especially when you consider that the FDA has approved other sunscreen chemicals that are obviously less safe than Mexoryl. Some opinions hold that Mexoryl is simply stuck in the FDA bureaucracy, a fact we could certainly believe. But others believe that U.S. sunscreen manufacturers are playing protectionist and pressuring the agency to withhold approval in order to save the industry from pricey licenses it would have to pay to French patent-holder L’oreal in order to add Mexoryl to American sunscreens.

Politics aside, we found plenty to like about Mexoryl as a sunscreen. Here’s a rundown of the information we uncovered:

• Mexoryl is derived from natural camphor, a material obtained from camphor laurel trees, a species of Asian evergreen.

• It’s been in use in other countries from Europe to South American for 13 years and has passed numerous safety tests.

• Mexoryl is the only sunscreen chemical that blocks all UVA rays and most UVB rays. The UVA radiation wavelength range is 320-400 nanometers. UVB radiation’s range is from 280-320 nanometers. Mexoryl protects against UV wavelengths from 290-400 nanometers so its coverage misses only the very first 10 nanometers of UVB radiation. (UVB radiation is responsible for sunburn. UVA is to blame for long term skin damage.) Mexoryl can protect skin from sunburn all by itself, but it must be combined with other active sunscreen agents to gain an official SPF rating.

• It's photostable. That means it does not degrade in sunlight. You only have to put it on once per day, and it works all day.

• It appears to biodegrade efficiently and to be non-toxic or of low toxicity to aquatic life. So when it rinses off it doesn't harm the environment.

• It is not absorbed by the human body to any great extent. One study found that less than 0.1% of a Mexoryl application is absorbed by the body. This finding indicates that Mexoryl is certainly safer than other sunscreens in that that very little of it enters the body. Because one must absorb something to have it cause internal harm, this is a promising finding.

• Though it should be noted that even small amounts of certain chemicals can cause harm, Mexoryl appears to be relatively benign. It’s water soluble, which means it is highly unlikely to build up in the fatty tissues of the body. Any that is absorbed is likely to be rinsed out quickly. This, in turn, is an indication that its potential to cause endocrine disruption and other long term/chronic harm is probably limited at best. Even if it were to be found that Mexoryl causes endocrine or other problems, it doesn't appear to hang around in the body long enough to trigger them.

While we’d like to see more data before making a definitive declaration that Mexoryl is safe to use and is our official sunscreen of choice, the preliminary information we uncovered in response to our alert reader’s letter quite clearly shows that Mexoryl is at the very least an extremely promising sunscreen alternative. It presents almost zero absorption potential and no bioaccumulation threat, biodegrades quickly, and offers comprehensive sun protection. Ingredients currently available for use in the United States cannot make these claims.

Of course, as we said at the outset, the chief problem with Mexoryl is that it’s not available in the U.S. However, readers who live near Canada will easily find preparations containing Mexoryl just across the border. And where the miracles of mail order meet the power of the internet, good things can happen as well. We found that a simple search at http://www.froogle.google.com produced a variety of options with a single mouse click.

This article originally appeared in "The Non-Toxic Times," an e-newsletter published by Seventh Generation. Each month, Seventh Generation researches their extensive library and network of experts to bring you important tips, resources and news about the issues that affect the health of your home, family and the environment.

Seventh Generation offers a full selection of non-toxic household products for a clean home, a healthy family, and a safer world. They are committed to providing products that perform as well as conventional products, and are also safe and environmentally responsible. For valuable coupons and to subscribe to their e-newsletter, "The Non-Toxic Times," visit www.seventhgeneration.com