1. Do some sunscreen ingredients and products really work better than others? continued...
Mexoryl (ecamsule), a UVA blocker approved in 2006 by the FDA, was judged as effective in a report on the sunscreen ingredient in a study published in Plastic and Reconstructive Surgery in 2007.
But the EWG found in its literature search that as much as 40% of Mexoryl can degrade within two hours, Sutton says.
Another new sunscreen addition, Helioplex, is a stabilizer used in sunscreens that combine avobenzone (a UVA sunscreen) and oxybenzone (a sunscreen that blocks UVB and some UVA). While they may be more stable, Helioplex products trigger the same concerns from EWG scientists as do other chemical blockers -- the risk of upsetting hormonal balance, Sutton says.
The bottom line: Physical blockers work better on both UVA and UVB rays, according to experts interviewed by WebMD.
2. Do some sunscreen ingredients really carry health risks?
Experts disagree, with some thinking they do and others saying the link is unproven.
Sutton thinks some ingredients are definitely hazardous, including oxybenzone. "We have animal studies that indicate we should be concerned about hormone disruption," she says. "Oxybenzone is found to have weak estrogenic effects in fish."
What some experts suspect happens is that the body interprets the presence of the chemical as some sort of hormone. "It could be turning on or off certain functions," she says. "The hormonal balance is becoming disrupted."
In laboratory studies, some sunscreen ingredients, including Padimate-O and Ensulizole, have been linked to cell mutations that can be linked to cancer, Sutton says.
But the official stance of the Skin Cancer Foundation is that oxybenzone is a "safe and effective UV filter," according to a spokesperson.
The American Academy of Dermatology has no official position on the use of oxybenzone sunscreens, a spokesperson says.
3. What do I look for when I go sunscreen shopping?
Sunscreens using physical blockers (titanium dioxide, zinc oxide) are preferred by EWG scientists and the doctors interviewed by WebMD.
For shopping help, see EWG's list of recommended brands at www.cosmeticsdatabase.com/special/sunscreens2008. Or ask your doctor to suggest a brand.
Choose a sunscreen with an SPF of 30 or higher, Badreshia-Bansal says. And know that SPF applies only to UVB rays.