Bemotrizinol on your skin: a safety profile

What is bemotrizinol?

The IUPAC name is 2,2'-((6-(((1,1'-biphenyl)-4-yl)amino)hexane-1,6-diyl)bis(azanediyl))bis(5-tert-butyl-4-hydroxybenzaldehyde dimethyl acetal).

Also known as: 2,2'-((6-(((1,1'-biphenyl)-4-yl)amino)hexane-1,6-diyl)bis(azanediyl))bis(5-tert-butyl-4-hydroxybenzaldehyde dimethyl acetal), Tinosorb S, BEMT, bis(1,1'-biphenyl)-4,4'-diamine N,N'-bis(ethylhexyl)-4'-hydroxy-3,3'-dimethyl-[1,1'-biphenyl]-4,4'-diyl bis(2-methylpropanoate).

IUPAC name

2,2'-((6-(((1,1'-biphenyl)-4-yl)amino)hexane-1,6-diyl)bis(azanediyl))bis(5-tert-butyl-4-hydroxybenzaldehyde dimethyl acetal)

CAS number

187393-00-6

Molecular formula

C42H44N4O8

Molecular weight

736.82 g/mol

SMILES

C=CC1CN2CCC1CC2C(C3=CC=NC4=CC=CC=C34)O.C1CC(=O)NC1C(=O)O

PubChem CID

6453371

Regulatory consensus

2 regulatory and scientific bodies have classified Bemotrizinol. The classifications differ — that's the data.

Regulators apply different standards of evidence — animal-data weighting, exposure-pattern assumptions, epidemiological power thresholds — which is why two scientific bodies can review the same data and reach different conclusions. The disagreement is the data.

Where you encounter bemotrizinol

• premium_sunscreen
• facial_sunscreen
• body_sunscreen
• water_resistant_sunscreen

Safer alternatives

Lower-risk approaches that achieve a similar outcome to Bemotrizinol:

• Mineral UV filters (zinc oxide, titanium dioxide) — no systemic absorption
  Trade-offs: Alternative approach; specific tradeoffs depend on application context, scale, and regulatory requirements. Full hazard assessment of alternative recommended before adoption to avoid regrettable substitution.
  Relative cost: 1.2-2×
• Newer-generation organic filters with lower skin penetration (e.g., bisoctrizole)
  Trade-offs: Alternative approach; specific tradeoffs depend on application context, scale, and regulatory requirements. Full hazard assessment of alternative recommended before adoption to avoid regrettable substitution.
  Relative cost: 2-5× conventional
• UPF-rated clothing and physical sun protection
  Trade-offs: Removes 95-99% of dissolved contaminants including metals, PFAS, nitrates; wastes 2-4 gallons per gallon produced (improving with newer systems); removes beneficial minerals; $0.05-0.25/gallon; requires pre-treatment for longevity.
  Relative cost: 1.2-2×

Frequently asked questions