Dimethyl Ether

Dimethyl ether is primarily used as a propellant/solvent in aerosols and is typically present at meaningful levels in leave-on spray products, with exposure risk increased by fine mist application. While not a common allergen, it can cause transient stinging/irritation and significant dryness/defatting of compromised skin, and direct contact (or occlusion) can worsen barrier disruption—especially in eczema-prone users. Given the real-world use pattern and vulnerability of sensitized skin, it warrants a mild irritancy score rather than being considered inert. Safety Notes: Dimethyl ether is used primarily as a liquefied propellant/solvent in OTC aerosol cosmetics (e.g., hair sprays, dry shampoos, antiperspirants, shaving foams, deodorant/body sprays), where it can appear at low single-digit levels in blended propellant systems. In high-strength consumer aerosol products, especially when used as the primary propellant, real-world formulations commonly place dimethyl ether in the ~30–60% range and can reach about 70–75% in some designs. It is essentially limited to leave-on aerosol formats (not typical for rinse-off creams/lotions), and practical limits are driven by flammability, package pressure, and VOC/labeling constraints rather than a fixed cosmetics-wide maximum.