Sun Bum sunscreens are free of oxybenzone and octinoxate, the two chemicals most strongly linked to coral reef damage and banned under Hawaii’s Act 104. That makes them compliant with current reef protection laws, but “reef safe” isn’t a regulated term, and the full picture depends on which Sun Bum product line you’re using.
What Sun Bum Leaves Out
All Sun Bum sunscreens are formulated without oxybenzone, octinoxate, parabens, phthalates, retinyl palmitate, and formaldehyde. Oxybenzone and octinoxate are the two ingredients that triggered Hawaii’s 2018 ban (Act 104), which prohibited the sale of non-prescription sunscreens containing either chemical starting January 1, 2021. Several other places, including Key West, the U.S. Virgin Islands, Bonaire, and Palau, have passed similar restrictions.
By excluding these two chemicals, every Sun Bum product meets the legal standard set by Hawaii and most other jurisdictions with sunscreen ingredient bans. Sun Bum labels its products “Hawaii Act 104 Compliant” rather than “reef safe,” which is a more honest description of what the formulation actually guarantees.
Mineral vs. Chemical Lines: A Real Difference
Sun Bum sells two distinct product lines, and they sit in different places on the reef safety spectrum.
The mineral line uses zinc oxide and titanium dioxide as active ingredients. These minerals sit on top of the skin and physically block UV rays. They don’t dissolve in water the same way chemical filters do, and they aren’t absorbed into skin tissue. Zinc oxide and titanium dioxide are widely considered the safest options for marine environments.
The original (chemical) line uses homosalate, octocrylene, octisalate, and avobenzone. These ingredients absorb UV radiation and convert it to heat. They pass Hawaii’s legal test because they aren’t oxybenzone or octinoxate, but that doesn’t mean they’re completely harmless to marine life. Lab studies on Symbiodinium, the algae that live inside coral tissue and keep reefs alive, have found that octocrylene can damage cell membranes, disrupt metabolic activity, and cause oxidative stress at elevated concentrations. Octinoxate is significantly more toxic than octocrylene in direct comparisons, but the fact that octocrylene still shows sub-lethal effects on coral symbionts means “law-compliant” and “harmless to reefs” aren’t the same thing.
Why “Reef Safe” Doesn’t Mean Much
No government agency regulates the phrase “reef safe.” The FDA has not defined it, and there’s no standardized test a sunscreen must pass to earn the label. Any brand can print it on a bottle. This is why Sun Bum specifically references Hawaii Act 104 compliance instead of making a broader reef safety claim.
The distinction matters when you’re shopping. A sunscreen labeled “reef safe” might still contain octocrylene or avobenzone. It might simply mean the product excluded oxybenzone. Without a legal definition, the term tells you almost nothing about what’s actually in the bottle. Reading the active ingredients panel is more useful than trusting any front-of-package marketing.
Where Chemical Sunscreens Aren’t Allowed
If you’re traveling to certain destinations, the mineral vs. chemical distinction becomes more than a preference. Sun Bum itself warns that some Hawaiian islands, specifically the Big Island, Maui, Lanai, and Molokai, have local legislation that prohibits non-mineral sunscreens entirely. In those locations, even Sun Bum’s original chemical line wouldn’t be appropriate despite being Act 104 compliant.
Palau’s restrictions are similarly strict. If you’re snorkeling, diving, or visiting marine protected areas anywhere in the tropics, mineral sunscreen is the safer legal and environmental choice.
The Best Option for Reef Protection
If minimizing your impact on coral is the priority, Sun Bum’s mineral sunscreen is the stronger choice. Zinc oxide and titanium dioxide have the least evidence of harm to marine organisms, and they satisfy even the strictest local bans worldwide.
Sun Bum’s original chemical line is a step up from sunscreens containing oxybenzone or octinoxate, but it still introduces chemicals like octocrylene into the water, and lab research shows those chemicals aren’t completely benign to coral symbiotic algae. For a beach day at a lake or a pool, that distinction is less important. For snorkeling over a reef in Hawaii or the Caribbean, it’s worth paying attention to.
Beyond your sunscreen choice, how you apply it also matters. Letting sunscreen absorb for 15 to 20 minutes before entering the water reduces how much washes off immediately. Wearing rash guards and UV-protective clothing means you need less sunscreen overall, which reduces the total chemical load entering the ocean regardless of which product you use.