Three generations of filters

Not all UV filters are the same. Between the octocrylene in a 2008 tube and Tinosorb A2B in a current Asian sunscreen formula sits twenty years of chemistry. We sort every filter approved in the EU and the US into three groups.

MODERN

These molecules were designed in the 1990s to 2010s specifically for broad UVA+UVB coverage and high photostability.

  • Tinosorb S (Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine) – 290–400 nm, photostable, stabilises other filters.
  • Tinosorb M (Methylene Bis-Benzotriazolyl Tetramethylbutylphenol) – an organic-mineral hybrid, micron-sized particles, UVA+UVB.
  • Tinosorb A2B (Tris-Biphenyl Triazine) – a newer filter, closes the short-wavelength UVB gap.
  • DHHB (Diethylamino Hydroxybenzoyl Hexyl Benzoate) – pure UVA, photostable, stabilises octinoxate if it is still in the formula.
  • Mexoryl XL (Drometrizole Trisiloxane) – L'Oréal patent, UVA+UVB, silicone structure, plays well with cosmetic bases.
  • Mexoryl SX (Ecamsule) – short-range UVA, often paired with Mexoryl XL.
  • Uvinul A Plus (Diethylamino Hydroxybenzoyl Hexyl Benzoate) – another trade name for DHHB.
  • Uvinul T 150 (Ethylhexyl Triazone) – the strongest UVB filter on the market per percent used.

These hold protection under the sun and cover the whole UVA2+UVA1+UVB range.

More: Tinosorb S.

LEGACY (approved, still on shelves)

Approved, but they protect worse than the modern filters or carry open safety questions.

Octinoxate (Ethylhexyl Methoxycinnamate)

UVB filter. Problems:

  • Endocrine activity in vivo (Klammer et al., 2007, Toxicology 238:192).
  • Photounstable: loses 40% in 35 minutes of UVB sun, so the formula needs a stabiliser (usually Tinosorb S or octocrylene).
  • Banned since 2021 in Hawaii and Palau.

Homosalate

Weak UVB filter. The SCCS capped it at 7.34% in the EU in 2021 over suspected hormonal activity. The US FDA still allows up to 15%, which is why European and American sunscreens differ here.

Octisalate (Ethylhexyl Salicylate)

Weak UVB filter, usually a "stabiliser" alongside others. On its own it gives little protection. No safety problem, but it takes up space in the formula where Uvinul T 150 would protect better.

Ensulizole (Phenylbenzimidazole Sulfonic Acid)

Water-soluble UVB filter, once used in light gels and fluids. Generates free radicals under the sun (Allen et al., 1996), now nearly gone from current formulas.

DISCOURAGED

Oxybenzone (Benzophenone-3)

  • Matta et al., 2019 (JAMA 321:2082) – systemic absorption under normal use exceeds the FDA 0.5 ng/mL threshold 188-fold by day four, which triggers a full safety reassessment under FDA rules.
  • Downs et al., 2016 – harm to coral reefs at 62 ppt in seawater.
  • Banned in Hawaii (SB 2571, 2018), Palau (2020), Key West (2019), and several Mexican reserves.
  • A known photocontact allergen.

More: oxybenzone.

Octocrylene

  • Downs et al., 2021 (Chemical Research in Toxicology 34:1046) – stored for a year or more, octocrylene degrades into benzophenone through a retro reaction. Benzophenone is classed 2B (possible carcinogen) by IARC.
  • The older the tube, the more benzophenone. A year-old octocrylene sunscreen is a benzophenone sunscreen.

Avobenzone (Butyl Methoxydibenzoylmethane)

Not dangerous on its own, but photounstable: loses 36% of its effect in an hour of UVA (Gaspar & Maia Campos, 2006). A good formula stabilises it with Tinosorb S or octocrylene; a bad one leaves it bare. Without a stabiliser avobenzone is pointless.

What to look for on the label

A good 2026 sunscreen carries at least two modern filters from the MODERN list. Working combinations in European formulas:

  • Tinosorb S + Uvinul T 150 + DHHB covers the full spectrum, stably.
  • Mexoryl XL + Mexoryl SX + Uvinul T 150, the L'Oréal classic.
  • Mineral: Zinc Oxide 15–25% (broad spectrum, physically stable).

What to cross off:

  • Octinoxate + avobenzone only is a 2005 formula.
  • Oxybenzone near the top means they put it back.
  • Octocrylene first among the filters makes the production date critical, check freshness.

The American problem

The FDA was slow to expand the list: bemotrizinol (Tinosorb S) is the first new active ingredient added to the over-the-counter sunscreen monograph since the late 1990s. The FDA order of 10 June 2026 allows it at up to 6% and took effect on 9 August 2026. That is why American sunscreen chemistry still lags behind European and Asian formulas. In the EU, Japan and Korea, Tinosorb S reached the mass market back in the 2000s. If you buy sunscreen abroad, read the INCI more carefully. The difference between a right and a wrong formula can be a single line.

More on octinoxate: octinoxate.