Absorbs UVB radiation
Water soluble, lightweight feel
Suits gel and spray formulas
Non comedogenic texture
Ensulizole Description
Ensulizole is a water soluble organic UVB filter, unusual among chemical filters because it is used as its sodium salt rather than an oil soluble compound. This water solubility makes it popular in lightweight, non greasy gel and spray sunscreens, since it partitions differently in a formula than oil soluble filters do.
Its conjugated aromatic ring system absorbs UVB radiation and converts the energy to heat, though photophysical research has found it can also generate a small amount of singlet oxygen in its excited state, which is part of why formulators often pair it with antioxidants or other stabilizers.
Ensulizole References
Ensulizole (phenylbenzimidazole 5 sulfonic acid) as a cause of facial dermatitis, two cases, Contact Dermatitis, 2006
Photophysical and photosensitizing characters of 2 phenylbenzimidazole 5 sulfonic acid, a theoretical study, Photochemistry and Photobiology, 2015
Our team reviews ingredient research and uses up-to-date evidence to rate ingredients based on the categories below.
Best
Ingredients with the most rigorous and convincing evidence. These are the standouts backed by consistent findings across independent, peer reviewed clinical research.. When we call an ingredient Best, it has earned that distinction through genuine, reproducible proof that it improves skin.
Good
Reliable, well tolerated ingredients that do their job without complaint. They may not carry the headline benefits of a Best rated active, but they hydrate, stabilize a formula, or support the ingredients around them in ways that make a real difference in how a product performs and feels.
Average
Ingredients that are perfectly safe and serve a clear function, typically as an emollient, thickener, or filler, but do not offer any meaningful skin benefit beyond that basic job. Not a red flag, just not a reason to choose one product over another.
Bad/Worst
Ingredients with documented potential to irritate skin, disrupt the barrier, or trigger sensitization in some users, often synthetic fragrance, drying forms of alcohol, or certain essential oils. Not automatically a dealbreaker for every skin type, but worth knowing about before you commit to a product.
