Padimate O
A PABA derivative that is now rarely used.
Banned in
- Palau
Also excluded where only mineral sunscreen is allowed
- Maui County
- Hawaiʻi County
Where it’s restricted
Named in the law or guidance
| Location | Status | Since |
|---|---|---|
| Palau law text ↗ | In force | January 1, 2020 |
Also not allowed under mineral-only rules
Padimate O isn’t named in these laws, but they allow only mineral (zinc oxide or titanium dioxide) sunscreens, so a product containing it is excluded anyway.
- Maui County (Maui, Molokaʻi, Lānaʻi) (in force since October 1, 2022)
- Hawaiʻi County (Big Island) (in force since December 1, 2022)
Why it’s regulated
In the US, FDA's 2021 proposed order said padimate O is not GRASE because more data are needed, and FDA states that this is not a finding that it is unsafe.
What the reef research says
Giraldo et al. (2017) tested OD-PABA (octyl dimethyl PABA), another name for padimate O, on three marine organisms: the microalga Isochrysis galbana, the mussel Mytilus galloprovincialis and the sea urchin Paracentrotus lividus. The authors reported EC10 values of 26.5 to 127 µg/L for OD-PABA and called the toxicity remarkable. They judged the risk from OD-PABA low (risk quotient 0.007), and the risk from octocrylene, which they tested alongside it, remarkable (0.27). A 2017 field survey in Hong Kong measured padimate O in coral tissue.
Sources (4)
- Giraldo et al. 2017, Archives of Environmental Contamination and Toxicology: Ecotoxicological evaluation of OD-PABA and octocrylene (PubMed 28391487)
- FDA: Questions and answers on FDA's regulatory actions on over-the-counter sunscreen
- National Academies (2022), Review of Fate, Exposure, and Effects of Sunscreens in Aquatic Environments, Appendix D Table D.3 (padimate O in coral tissue)
- 21 CFR 352.10, Sunscreen active ingredients (eCFR; ensulizole, meradimate, octinoxate and octisalate appear under their revised names in the stayed 2002 amendment)
What to look for instead
Related ingredients: Octocrylene, PABA (Aminobenzoic Acid)
Last reviewed October 14, 2026.