Tinosorb M (also known as bisoctrizole or methylene bis-benzotriazolyl tetramethylbutylphenol) is an organic and nanoparticle sunscreen filter which covers UVA and UVB rays.
Tinosorb M both reflects and absorbs UV rays so it is considered a chemical and physical sunscreen at the same time, that happens because its organic structure also contains nano particles.
It has been formulated to be oil soluble since it helps keeping efficacy and its color is white so most sunscreens that include Tinosorb M will tend to leave an slightly white cast depending on the quantity used (in Europe the maximum quantity of tinosorb M allowed is a 10%).
Tinosorb M spectrum range and stability
Bisoctrizole covers 280-400nm broad-spectrum and its peak protection is between 303-358nm, is highly compatible with other sunscreen filters since no sunscreen filter can actually provide a full spectrum protection by itself.
It has a high photostability and doesn’t degrade under sunlight. Due to its high stability, it is commonly used to stabilize other unstable sunscreen such as octinoxate.
Tinosorb M does not produce free radicals and does not produce skin photosensibility problems, being able to enhance skin defence and to prevent erythemas and burns with a high efficacy.
Tinosorb M absorption and body effects
Despite the lack of studies on bisoctrizole safety, it is actually one of the most safest sunscreen filters since it doesn’t penetrate in the skin and doesn’t have estrogenic effects.
Tinosorb M allergies
Rare cases of allergic contact dermatitis have been reported.