[sidebar]CHEMICAL SUNSCREENSThe key components of these skin safeguards are listed on the Drug Facts portion of the bottle and recognizable by the endings of their names: –ene, –one, or –ate. These ingredients absorb UV rays, keeping them from penetrating skin deeply enough to cause damage. Some take in only UVB light, which causes sunburn, while others also thwart UVA rays, linked to wrinkles and cancer. Benefits: “Chemical sunscreens provide more versatility in product formulations and are less likely to be seen on the skin,” says Diana Howard, PhD, vice president of global education and research and development for the International Dermal Institute. In other words, they won’t leave you with a Kabuki-like white mask on your face. Health concerns? A recent study in Environmental Science & Technology suggested a link between benzophenone-type ingredients, including oxybenzone, often used because it’s effective at absorbing UVA light, and endometriosis, a disorder that occurs when cells like those that line the uterus grow in other areas of the body. Oxybenzone has also been shown to cause hormone disruption in cancer cells. The FDA, however, believes that the chemicals are safe, as do many dermatologists, including Steven Q. Wang, MD, a director of dermatologic surgery and dermatology at Memorial Sloan Kettering Cancer Center in Basking Ridge, NJ, who has published a review of research linking sunscreens to health concerns. Dr. Wang says that the studies don’t prove cause and effect, and many of them are inconclusive. “But once the FDA approves newer UVA absorbers, more companies will move away from oxybenzone for fear of bad public relations,” he says. Parrot Head Fins Up Sport Broad Spectrum SPF 50 Sunscreen ($12; drugstore.com) is an oxybenzone-free option.   PHYSICAL SUNSCREENSSometimes called natural or mineral sunscreens, the two approved in the United States are titanium dioxide and zinc oxide. “They sit on the surface of the skin and reflect UVA and UVB rays,” says Dr. Howard. Benefits: “These are better for people with sensitive skin, because they’re less likely to cause redness, irritation, or stinging,” says Kavita Mariwalla, MD, an assistant professor of dermatology at Stony Brook University. “They’re also great for when you’re playing sports and sweating a lot, since they’re less likely to hurt if they get in your eyes.” (No one wants to lose at beach volleyball because of a sunscreen injury.) A good one to try: Aveeno Natural Protection Sunscreen Broad Spectrum SPF 50 ($11; drugstores). Health concerns? “There is no research I know of that links these ingredients to health concerns,” says Dr. Mariwalla. More from Prevention: 7 Habits Of Highly Effect Skin Care