Sodium Trideceth Sulfate

Sodium Trideceth Sulfate is an anionic sulfate surfactant used primarily for cleansing/foaming, typically in rinse-off products where it can still disrupt stratum corneum lipids and increase transepidermal water loss. Sulfate surfactants are consistently associated with higher irritation in patch testing and real-world use, with risk amplified in eczema, barrier-compromised, or facial skin even at standard cleanser concentrations. Given its surfactant class and barrier-stripping potential, I score it as a significant irritant requiring caution for sensitive populations. Safety Notes: Sodium Trideceth Sulfate is primarily used as an anionic surfactant in rinse-off cleansing products; at the low end (~0.5–2%) it appears in mild facial cleansers and syndet-style washes where it is blended with amphoterics/nonionics to reduce irritation while still boosting foam and detergency. The high end (~10–15% active) is observed in stronger, consumer-available clarifying shampoos, body washes, and some acne/oily-skin cleansers where higher surfactant actives are used for enhanced soil/sebum removal. It is rarely used in leave-on products (functionally impractical due to irritation and residue), so the observed market range is effectively for rinse-off formulations.