Bisoctrizole
Bisoctrizole is a benzotriazole-based organic compound that is added to sunscreens to absorb UV rays.
Bisoctrizole is a broad-spectrum ultraviolet radiation absorber, absorbing UVB as well as UVA rays. It also reflects and scatters UV. Bisoctrizole is a hybrid UV absorber, an organic UV filter produced in microfine organic particles, like microfine zinc oxide and titanium dioxide. Where other organic UV absorbers need to be dissolved in either the oil or water phase, bisoctrizole dissolves poorly in both and is applied as invisible particle.
Bisoctrizole is added to the water phase of a sunscreen as a 50% suspension, whereas mineral micropigments are usually added to the oil phase. The bisoctrizole particles are stabilized by the surfactant decyl glucoside.
Bisoctrizole shows very little photodegradation and has a stabilizing effect on other UV absorbers, octyl methoxycinnamate in particular.
When formulated into a sunscreen, bisoctrizole has minimal skin penetration and it shows no estrogenic effects in vitro.
Bisoctrizole is not approved by the U.S. Food and Drug Administration, but is approved in the EU and other parts of the world.
