Silica Silylate

Silica silylate is a hydrophobic fumed silica used as a thickener/texture agent and oil-absorbing powder, typically at low concentrations (about 0.1–5%) and is generally considered non-reactive on skin. Clinical experience and patch testing data suggest low irritation potential, but the particulate nature can be mildly drying or mechanically irritating in highly compromised barrier states (e.g., severe eczema or post-procedure skin), so it is not scored as completely inert for ultra-sensitive populations. Safety Notes: In commercial leave-on skincare and color cosmetics, silica silylate is often used at very low levels (~0.05–0.5%) as a rheology modifier/suspending aid (e.g., to stabilize oils, pigments, UV filters) and to boost slip/soft-focus in serums, sunscreens, and primers. Higher-load consumer products (notably oil-based primers, blurring powders, oil-control balms, and some anhydrous silicone/oil gels) can reach ~10–25% when it functions as a primary gellant/structurant and strong mattifying filler; these levels are observed in OTC retail products rather than prescription/professional-only items. There is no specific EU/FDA maximum for silica silylate in cosmetics, so the practical upper bound is set by sensory, clarity/whiteness, viscosity, and dispersion limits rather than regulation.