Potassium Laurate

Potassium laurate is a potassium soap (fatty acid salt) used as a cleansing surfactant; at typical functional levels in cleansers/soap systems it can be strongly defatting and inherently alkaline, both of which disrupt the stratum corneum and increase stinging and barrier damage. Clinical experience and patch-test/irritancy data for soap-type anionic surfactants consistently show higher irritation potential than milder syndets, especially in eczema and compromised skin. Because exposure is often repeated and cumulative in routines (handwashing, facial cleansing), I score it high for sensitive-skin safety. Safety Notes: Potassium laurate is a soap-type anionic surfactant used primarily in rinse-off cleansers (liquid soaps, acne washes, and some traditional/“natural” cleansing gels); in multi-surfactant systems it can appear at low levels (~0.1–1%) as a secondary surfactant/pH-dependent soap fraction. At the high end, consumer-available liquid castile/soap concentrates and high-alkali facial/body washes can reach roughly 10–25% potassium laurate (or equivalent active soap content) when formulated as true soap-based cleansers; it is uncommon in leave-on products due to high alkalinity/irritation potential and stability constraints, so leave-on uses are typically at the low end if present at all.