TRIETHYLAMINE.

Triethylamine serves a clear functional role as a pH adjuster and emulsion stabilizer, meaning it is not an ingredient typically 'dusted' for questionable or sub-efficacious claims. However, its potent basicity and severe toxicity profile, including documented skin burns and eye damage, render it a significant safety concern. The lack of a determined safe maximum concentration for cosmetic use further underscores its unsuitability for precision skincare formulations.

Triethylamine is classified as toxic if swallowed, in contact with skin, or if inhaled, causing severe skin burns and serious eye damage. Acute vapor exposure can induce eye irritation, corneal swelling, and halo vision in humans, in addition to irritating skin and mucous membranes. Chronic exposure has resulted in reversible corneal edema, respiratory and hematological issues, and ocular lesions in animal studies. A 70% solution applied to guinea pig skin produced severe irritation and extensive tissue necrosis. The EPA has not classified it for carcinogenicity. It is listed as a California Safe Cosmetics Program (CSCP) Reportable Ingredient due to documented neurotoxicity, ocular toxicity, and respiratory toxicity concerns, particularly when used as a fragrance or flavor component.