Reef Safe Sunscreen: What It Actually Means

Walk into any surf shop, beach resort, or outdoor retailer and you will see dozens of sunscreens labeled reef safe. The problem: that term is not regulated. There is no legal definition, no certification standard, and no third-party verification required to put those words on a bottle.

So what does reef safe actually mean? And how do you choose a sunscreen that genuinely protects the ocean?

The Ingredients That Harm Coral Reefs

The research on sunscreen and reef damage centers on two chemical UV filters: oxybenzone and octinoxate. Both have been shown to cause coral bleaching, disrupt the development of juvenile coral, and accumulate in reef ecosystems at concentrations that cause measurable harm.

A 2015 study found that oxybenzone could cause bleaching, DNA damage, and deformities in coral larvae at concentrations as low as 62 parts per trillion -- equivalent to a single drop in 6.5 Olympic swimming pools. The research prompted Hawaii to become the first state to ban both oxybenzone and octinoxate in sunscreens sold or distributed in the state, with the law taking effect in 2021.

Since then, Palau, Bonaire, the US Virgin Islands, and several other coastal destinations have implemented similar bans. The scientific consensus on oxybenzone's harm to marine ecosystems is strong.

What Reef Safe Actually Requires

A genuinely reef safe sunscreen should be free of oxybenzone and octinoxate at minimum. Some formulations also avoid octocrylene, homosalate, and avobenzone, which have shown potential for marine toxicity in preliminary research, though the evidence is less conclusive than for oxybenzone and octinoxate.

Mineral sunscreens using zinc oxide and titanium dioxide as their only active ingredients are considered the safest choice for marine environments. Zinc oxide and titanium dioxide do not bioaccumulate in marine ecosystems and have not been associated with the coral bleaching effects documented with oxybenzone.

Why Most Sunscreen Washes Off Into the Water

Even a reef safe sunscreen ends up in the water if it washes off your skin during swimming. This is where water resistance becomes relevant not just for your protection but for the ocean's health too.

A formula that stays bonded to your skin through water exposure is doing less environmental damage than one that disperses into the water column within the first few minutes of your swim. SolRX Waterblock formulas are independently tested to maintain their SPF rating after 8 hours of water immersion, which means more of the formula stays on your skin and less enters the marine environment.

How to Read a Sunscreen Label for Reef Safety

Turn the bottle over and look at the active ingredients. If you see oxybenzone or octinoxate, the formula is not reef safe regardless of what the front label says. If the only active ingredients are zinc oxide and/or titanium dioxide, you have a genuinely reef safe formula.

Inactive ingredients can also matter for coral health, but oxybenzone and octinoxate are the primary concerns backed by the strongest scientific evidence.

SolRX and Reef Safety

All SolRX formulas are oxybenzone free and octinoxate free. Our mineral range uses zinc oxide as the sole active ingredient, meeting the strictest definition of reef safe formulation. SolRX is also compliant with Hawaii Act 104, the landmark legislation that established the first government-mandated ban on reef-harmful sunscreen ingredients.

Taking care of your skin and taking care of the ocean should not be a trade-off. With the right formula, they are not.