Ricinus Communis Seed Oil

Ricinus Communis (castor) seed oil is primarily an emollient/occlusive used at moderate to high concentrations in balms, cleansers, and lip products, and it is generally well-tolerated. However, clinical patch-test data and case reports document occasional irritant or allergic contact dermatitis (more likely in compromised skin and with impure/oxidized oil), so it cannot be scored as very gentle or inert. Given its overall low but real reactivity potential in sensitive populations, a gentle-risk score is most appropriate. Safety Notes: In commercial skincare, castor oil is often used at very low levels (~0.1–1%) as an emollient/viscosity-building oil in creams, cleansers, and makeup-removing balms, especially when it is not a hero ingredient. At the high end, it is sold to consumers as straight castor oil (100%) and is also used at very high levels (typically 50–95%) in anhydrous leave-on balms, oil serums, cleansing oils, and lip products where it contributes gloss, film-forming, and texture. No specific EU/FDA concentration limit applies for this ingredient in cosmetics; practical maxima are driven by sensorial and stability considerations rather than regulation.