Science
Mechanism of Action
Triethanolamine primarily acts as a pH adjuster, or buffer, by interacting with acidic compounds to lower their pH, or by stabilizing higher pH levels to maintain the product's optimal, skin-friendly range (typically pH 5-7). Its amphiphilic nature allows it to serve as an effective emulsifier, facilitating the homogeneous dispersion of oil and water in a formula. Additionally, it can reduce surface tension as a surfactant and contribute to product viscosity as a thickener, enhancing the overall body and density of the formulation.
Research
Clinical Evidence
High confidence2.5%
Key findings
- 01 Clinical data indicates concentrations between 1-3% are safe for topical application, demonstrating no skin irritation or adverse effects in general use.
- 02 The Cosmetic Ingredient Review (CIR) Expert Panel has deemed triethanolamine safe for leave-on cosmetic products at concentrations up to 2.5%, assuming proper formulation to be non-irritating and free of excessive diethanolamine.
- 03 A repeated insult patch test (RIPT) involving 110 individuals showed no sensitization at 5% concentration, though some subjects experienced erythema during induction, suggesting concentration-dependent effects.
Transparency
Dusting Analysis
Triethanolamine is a functional formulating ingredient, not an active ingredient marketed for direct skin benefits. Its primary roles are pH adjustment and emulsification, making 'dusting' of its benefits irrelevant. Usage is strictly governed by safety thresholds rather than perceived efficacy boosts at higher concentrations; exceeding recommended levels poses a safety risk, not enhanced performance.
The Formula
Formulation
Stability
Triethanolamine contributes significantly to product longevity by maintaining optimal pH levels across various temperatures and conditions. A 1% aqueous solution of TEA has a pH of approximately 10.5, thus formulators must ensure the final product pH is between 5 and 7 to prevent potential skin irritation and ensure stability.
Conflicts
- N-nitrosating agents (e.g., 2-Bromo-2-Nitropropane-1,3-Diol, 5-Bromo-5-Nitro-1,3-Dioxane, sodium nitrate) due to the potential formation of carcinogenic nitrosamines, a risk minimized by careful formulation.
- Strong acids (e.g., 20% ascorbic acid), which can destabilize the formulation.
- High-salt ingredients, which may compromise stability.
Safety
Safety Profile
The Cosmetic Ingredient Review (CIR) Expert Panel considers Triethanolamine safe for use in cosmetics when formulated to be non-irritating and when levels of free diethanolamine are minimized. For leave-on products, a maximum concentration of 2.5% is deemed safe. While an older assessment suggested up to 5% for prolonged skin contact, current recommendations emphasize lower levels for leave-on applications. Usage should strictly avoid combination with N-nitrosating agents to prevent the formation of potentially carcinogenic nitrosamines, although this risk is considered negligible with proper formulation. High concentrations (>5%) or an unbalanced pH can lead to allergic reactions or skin irritation, particularly for sensitive individuals. The FDA permits its use with strict limits in cosmetics.
Your Skin
Skin Compatibility
Our Assessment
Verdict
Triethanolamine is a valuable formulating agent, primarily used as a pH adjuster and emulsifier to enhance product stability and texture within specific, carefully monitored concentration limits, proving compatible with all skin types at appropriate usage levels.
Related
Similar Ingredients
Finding similar ingredients…