Sisymbrium Irio Seed Oil

Sisymbrium irio (London rocket) seed oil is primarily an emollient lipid used at low percentages to improve slip and barrier feel, but it comes from a Brassicaceae seed source that can contain bioactive minor components (e.g., glucosinolate breakdown products) that are not as well-characterized for tolerability as more common seed oils. Clinical irritation/sensitization data are limited, so for highly reactive or eczematous patients I cannot classify it as “very gentle” despite typical low use levels. Given the uncertainty and the potential for idiosyncratic reactions in compromised skin, a mild irritancy score best reflects patient-safety-first risk management. Safety Notes: In commercial skincare, Sisymbrium Irio Seed Oil is most often used as a minor emollient/conditioning specialty oil in leave-on formulas (serums, creams, facial oils) at trace-to-low levels (~0.01–1%) to support sensory feel and marketing claims, and occasionally a few percent in anhydrous blends. At the high end, consumer-available single-ingredient or near-neat botanical oils can be marketed as 100% seed oil (or functionally neat), making 100% the observed maximum for OTC leave-on oils; rinse-off usage is typically at the lower end due to cost and wash-off inefficiency.