Methylene Bis-Benzotriazolyl Tetramethylbutylphenol (also known as Bisoctrizole or Tinosorb M) is an organic-particulate UV filter that provides broad-spectrum UVA and UVB protection through absorption, reflection, and scattering. In nano form it is micronized to improve dispersion and photoprotective efficiency in sunscreen formulations.
| Reported effect | How often | Notes |
|---|---|---|
| Contact irritation (mild redness or stinging) | Rare | Generally considered well tolerated; irritation is infrequent and usually mild. |
| Allergic contact dermatitis | Very rare | Isolated case reports; sensitization potential is low compared with some older UV filters. |
| Eye irritation | Rare | Can occur if product migrates into the eyes during application. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.