Chemical filter

DHHB

Photostable modern UVA filter. The parent molecule looks good; the live issue is a phthalate impurity from manufacture, not DHHB itself.

DHHB is a photostable UVA filter with a peak near 354 nm. It is a common replacement or partner for avobenzone in European and Australian formulas. Australia and the EU allow 10%.

The parent filter has a favourable safety profile and low expected systemic risk at permitted use. The current regulatory attention is a manufacturing contaminant, di-n-hexyl phthalate (DnHexP). SCCS calculated 260 ppm of DnHexP in the raw filter as toxicologically acceptable when DHHB is used at 10% and recommended 1 ppm as a technically achievable target, and Commission Regulation (EU) 2026/909 has set a legal cap of 10 ppm, with a transition period for products already on the market.

That is an impurity-control problem, not evidence that DHHB is an endocrine disruptor. Prefer suppliers that can show a low DnHexP spec.

Sources

Sunscreens with DHHB

Are we sloppy? Tell Gus.