Unfortunately, health experts will likely be debating the safety of sunscreens long after the FDA finally gets around to doing it. Case in point: A very public disagreement between the Environmental Working Group (EWG) and a trio of scientists over the safety of retinyl palmitate, a form of vitamin A, and an additive used, not only in sunscreens, but in dairy products and other processed foods.

The dispute stems from a recent analysis published in the Journal of the American Academy of Dermatology (no abstract link available), dismissing an advisory in the EWG's 2010 Sunscreen Guide that highlighted safety concerns about retinyl palmitate as a carcinogenic substance triggering cancer in humans.

The EWG feels the ongoing research by the FDA and the National Toxicology Program on animals has suggested retinyl palmitate may be carcinogenic when skin is exposed to sunlight. This, coupled with the fact that various forms of vitamin A can be found in 41 percent of the sunscreens in America, prompted the EWG to recommend avoiding retinyl palmitate.

Conversely, the scientists involved in the Journal report argue that retinyl palmitate isn't an active ingredient in sunscreens, and works in concert with other antioxidants "to alleviate the risk of free radical formation seen in these in vitro experiments." And, they were very skeptical that the results of an NTP study involving hairless and albino mice that developed tumors more quickly when coated with retinyl palmitate couldn't be easily linked to humans.

Interestingly, there's one thing, upon which, both groups agree: Limiting heavy exposure (look for the shade) and wearing protective clothing (hats, sunglasses and long-sleeve shirts and pants) -- but not sunscreens -- should be your primary strategy for protecting your skin from the sun.

Consulting Room August 10, 2010

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Environmental Working Group August 11, 2010

Environmental Working Group August 2010