The 8 Best Reef-Friendly Sunscreens, According to Dermatologists

It's well-known that overexposure to UV rays can cause premature skin aging and increase your risk of skin cancer. And it's no secret that sunscreen plays an important role in protecting your skin from those UV rays. Depending on the type you slather on, however, your go-to sunscreen may be protecting your skin at the expense of coral reefs—one of the most valuable ecosystems on earth.

According to the US Environmental Protection Agency (EPA), an estimated 25% of all marine life depends on coral reefs for survival. They're also a source of food and new medicines, not to mention they protect coastlines from storms and erosion by shielding the shoreline from waves, per the California Academy of Sciences.

"Coral reefs are dying at an alarmingly accelerated rate, and some environmentalists are concerned that sunscreen ingredients, particularly from chemical sunscreens, are contributing to coral reef bleaching," says Susan Massick, M.D., associate clinical professor of dermatology at The Ohio State University Wexner Medical Center. "The current theory is these sunscreens, with ingredients like oxybenzone and octinoxate, wash off in the water and settle into the coral reefs, thus affecting reef reproduction."

Once their life cycles are disrupted, coral reefs are no longer able to sustain themselves and slowly start to die off, noted by loss of color, according to the National Oceanic and Atmospheric Administration (NOAA).

While the loss of coral reefs is multifactorial and can't be attributed to chemical sunscreens alone, it's one aspect we can easily do something about by making the switch to reef-friendly sunscreens.

How to Choose the Best Reef-Safe Sunscreens

Because the term "reef-friendly" isn't regulated, and there's no clear definition of the term being used among manufacturers, it's important to read the label yourself to make sure the sunscreen you're considering doesn't include reef-harming ingredients. (To be extra diligent, you can also browse sunscreen brand websites to see if they provide intel on how they specifically go about defining "reef-friendly.")

What designates a sunscreen as reef-friendly are the specific ingredients. Reef-friendly sunscreens are those that don't contain chemical ingredients, with the biggest offenders being oxybenzone (also called benzophenone-3 and BP-3), octinoxate, mineral oil (petrolatum), 4-methylbenzylidene camphor (4-MBC), octocrylene, para-aminobenzoic acid (PABA), parabens and triclosan.

Reef-friendly sunscreens, on the other hand, are mineral-based and provide the necessary broad-spectrum UVA and UVB coverage with the ingredients titanium dioxide and zinc oxide.

"Rather than absorb into the skin like chemical sunscreens, these minerals sit on top and act as a shield, reflecting the sun's rays away from the skin," says New York City-based cosmetic dermatologist Michele Green, M.D.

Mineral sunscreens fall under two categories: those with nanoparticles and those without, with non-nano sunscreens being the reef-friendly choice.

When nano-size (smaller) particles are present in mineral sunscreens, they're much easier to rub into the skin and don't leave an opaque white film behind—but the smaller the particles, the easier they can be ingested by corals and disrupt the ecosystem.

Non-nano sunscreens, with a particle size greater than 100 nanometers, are considered reef-friendly. "The large particle size of the minerals can't be ingested by the corals," says Green.

The Best Reef-Safe Sunscreens, According to Dermatologists

1. Kokua Sun Care SPF 50 Natural Zinc Sunscreen

This water-resistant zinc sunscreen by Kokua Sun Care provides broad-spectrum protection using the highest percentage (25%) of non-nano zinc oxide available as the only active ingredient. It also goes on like a moisturizing lotion and rubs in clear and smooth.