Octisalate vs Padimate O: which is worse?

What is Octisalate?

Octisalate (INCI: Ethylhexyl Salicylate) is an oil-soluble UVB-absorbing chemical sunscreen active. It is primarily used as a UVB filter and photostabilizer for avobenzone.

What is Padimate O?

Padimate O (octyl dimethyl PABA) is an oil-soluble UVB-absorbing UV filter derived from PABA (para-aminobenzoic acid). It was once one of the most common UVB filters in US sunscreens but has declined in use since the 1990s.

Documented risks

Octisalate: Octisalate is FDA-approved at up to 5% and EU-permitted at up to 5%. It has a good safety record and low sensitization rate. The 2019 FDA absorption study detected systemic absorption above the 0.5 ng/mL threshold, warranting further study. This does not indicate known harm. It is a salicylate; those with aspirin sensitivity should note the structural relationship, though reactions are rare.

Padimate O: Padimate O is FDA-approved at up to 8%. It is a PABA derivative and carries a rare risk of photoallergic contact dermatitis in individuals sensitive to PABA-related compounds. There are some in vitro studies suggesting potential DNA damage from padimate O under UV exposure, though this has not been substantiated in human studies at cosmetic use levels. The CIR has assessed it as safe. Its use has largely been replaced by more modern, better-tolerated filters.