Benzophenone-4

Tolerability and safety

Irritation potential

Low

Allergen risk

Moderate

Pregnancy

Caution

Suitable for

Normal, Oily, Combination

Use with caution

Sensitive

About this ingredient

Benzophenone-4 (Sulisobenzone) is a water-soluble organic UV filter with coverage across UVB and short UVA (290–360 nm). The sulfonate group makes the molecule polar and compatible with the aqueous phase of formulations – hence its place in clear gels and sprays. Mechanism. Absorbs UV photons and converts the energy to heat via reversible keto–enol tautomerism. Does not reflect light, unlike physical filters. Often combined with avobenzone to cover long-wave UVA and with titanium dioxide for extra UVB. Where applied. Sunscreen gels and sprays, tinted SPF liquid foundations, hair products with anti-fade protection, sports SPF formulas for pool and swimming. EU concentration up to 5%. In Spain part of ISDIN Fotoprotector Spray, Heliocare Color, and some Avène Eau Thermale Sunscreen lines. Safety. SCCS opinion 2008 confirmed safety at concentrations up to 5%. Allergic contact dermatitis in 0.5–1% of patients – more common than with newer filters such as Tinosorb S. Sensitisation occurs mainly in patients with systemic lupus erythematosus, photodermatoses, and long-term users. Not to be confused with benzophenone-3 (oxybenzone), which has stronger endocrine-activity signals and is being phased back in the EU. Pregnancy and lactation – use with caution. No direct endocrine activity for benzophenone-4 in human studies, but EFSA has requested more data on the benzophenone family. AEMPS does not ban it, but in pregnancy clinicians prefer physical filters (titanium dioxide, zinc oxide) and Tinosorb S/M. Controversies. Hawaii's 2018 ban applies to benzophenone-3 (oxybenzone) and octinoxate – benzophenone-4 is not banned, but the photofilter debate is active. EU and AEMPS monitor the data; no formal restrictions as of May 2026. Realistic assessment. A workable UVB–short UVA filter for clear formulas. Not a first pick in patients with photosensitive skin and systemic autoimmune disease. A good alternative is Tinosorb S or 4MBC in patients with a photo-allergy history.

Frequently asked questions