Oxybenzone & octinoxate
UV filters banned in several reef jurisdictions and absorbed systemically at measurable levels.
Also listed as: benzophenone-3, octyl methoxycinnamate, chemical UV filters
What it is
Oxybenzone and octinoxate are organic UV filters that absorb ultraviolet radiation and dissipate it as heat. They are cheap, cosmetically elegant and used across sunscreens, foundations and lip balms.
Why it's worth avoiding
Both are absorbed through skin into plasma at concentrations far above the FDA's threshold for toxicology waiver, and both are implicated in coral bleaching and larval deformity in laboratory studies.
What the evidence says
FDA's 2019–2020 maximal-use trials (JAMA) found plasma oxybenzone concentrations over 180 ng/mL, versus the 0.5 ng/mL waiver threshold. Downs et al. (2016) documented coral larval toxicity at low parts-per-trillion oxybenzone.
How it's regulated
Hawaii, Key West, Palau, Bonaire, the US Virgin Islands and Aruba restrict oxybenzone and octinoxate sunscreens. The EU caps oxybenzone at 6% and requires a warning label.
Label clues
- Oxybenzone / benzophenone-3, octinoxate, octocrylene, homosalate in the active list
- 'Reef-friendly' with no filter list — the term is unregulated
- Spray sunscreens where inhalation is also a factor
Safer swaps
- Non-nano zinc oxide mineral sunscreen (SPF 30+, broad spectrum)
- EU/Asia-market filters such as Tinosorb S/M and Uvinul A Plus
- UPF 50+ clothing, hats and shade as the first line of defence
- Sticks and lotions instead of aerosol sprays
Where it shows up
Frequently asked
Should I stop using sunscreen?+
Absolutely not. Skin cancer risk is well established and immediate. Switch filters — non-nano zinc oxide is the widely-available mineral option — rather than skipping protection.
Is 'reef-safe' a regulated claim?+
No. There is no legal definition anywhere. Read the active-ingredient list: non-nano zinc oxide only is the most defensible formulation.