Sodium Polyacrylate Starch

Sodium Polyacrylate Starch is a superabsorbent polymer blend used primarily as a thickener/absorbent and film-former at low concentrations in leave-on and rinse-off products. Available patch-test and safety assessments for polyacrylate/starch-based rheology modifiers generally show low irritation potential, with reactions being uncommon and typically related to compromised barriers or formulation factors rather than the polymer itself. Given the very low intrinsic reactivity but acknowledging rare irritant responses in highly sensitized eczema patients (especially with occlusion), a 0.2 score best reflects typical clinical tolerability while staying cautious for severely reactive skin. Safety Notes: In commercial skincare, sodium polyacrylate starch (a superabsorbent polymer/thickener) is observed at very low levels (~0.05–0.3%) as a secondary rheology modifier/sensory powder in leave-on lotions/creams and some rinse-off cleansers. More commonly it sits around ~0.3–3% when used as a primary thickener/absorbent to build gel-cream textures and reduce tack in leave-on products. High-strength consumer products such as oil-control “dry touch” creams, balm-like leave-ons, and some waterless or high-solids texture products can reach ~5–8%, with higher levels typically limited by feel (powdery/drag), processing viscosity, and stability rather than specific regulatory caps.