Triethanolamine, often listed as TEA on ingredient labels, is a pH adjuster and emulsifier found in cleansers, moisturizers, sunscreens, and gel-based skincare products. It doesn’t treat your skin directly. Instead, it works behind the scenes to make sure the other ingredients in your product stay blended, effective, and at the right acidity level for your skin.
What Triethanolamine Actually Does
Skincare formulas are a balancing act. Oil and water don’t naturally mix, acids can be too harsh, and gels need something to give them structure. Triethanolamine handles all three of these problems depending on the product.
Its most common job is adjusting pH. Your skin’s surface sits at a slightly acidic pH (around 4.5 to 5.5), and products that fall too far outside that range can irritate or compromise your skin barrier. TEA is mildly alkaline, meaning it raises the pH of acidic formulations to bring them into a comfortable range. Chemically, it accepts a hydrogen ion from the solution, which nudges the overall acidity down.
TEA also works as an emulsifier. When combined with a fatty acid like stearic acid or oleic acid, it forms a type of soap that lowers the surface tension between oil and water phases. This keeps lotions and creams from separating into layers in the bottle. Without an emulsifier, your moisturizer would need shaking before every use and still wouldn’t apply evenly.
How It Creates Gel Textures
If you’ve ever used a lightweight serum or clear gel that feels smooth and holds its shape, there’s a good chance triethanolamine played a role. Many gel products use a thickening polymer called carbomer, which starts as a powder dispersed in water. On its own, carbomer doesn’t thicken much. It needs to be neutralized, meaning its acidic groups need to be deactivated by a base, before the polymer chains swell and create that familiar gel texture.
TEA is one of the most widely used neutralizers for this purpose. Research on carbomer gels shows that once neutralized with triethanolamine, these formulations remain stable and effective across a pH range of 5.0 to 8.0, which comfortably covers what’s safe for skin. The result is a clean, even gel that spreads easily and absorbs without leaving residue.
Where You’ll Find It
Triethanolamine appears across a surprisingly wide range of product types. According to EWG’s Skin Deep database, common categories include facial cleansers, facial moisturizers and treatments, body moisturizers, and even baby sunscreens. You’ll also find it in eye creams, shaving creams, foundations, and hair styling products. It’s not limited to one format or price point. Drugstore cleansers and high-end serums alike rely on it for the same basic formulation work.
In most of these products, TEA is present at low concentrations. It’s a functional ingredient, not an active one, so formulators use only as much as needed to hit the target pH or stabilize the emulsion.
Safety and Skin Sensitivity
The sensitization risk from triethanolamine is very low. A large-scale analysis from the Information Network of Departments of Dermatology (IVDK) patch-tested over 85,000 patients with triethanolamine at 2.5% concentration. Only 0.4% tested positive for a reaction, and researchers found no specific type of exposure that increased the risk of becoming sensitized. For an ingredient used in thousands of products worldwide, that’s a reassuringly small number.
That said, no ingredient is universally tolerated. If you have highly reactive skin or a known sensitivity to amines, it’s worth noting TEA’s presence on an ingredient list. But for the vast majority of people, it passes through their skincare routine without causing any issues.
The Nitrosamine Question
One safety concern that comes up repeatedly with triethanolamine is nitrosamine contamination. Nitrosamines are potentially harmful compounds that can form when certain types of amines react with nitrosating agents (substances that donate a nitrogen-oxygen group). TEA is a tertiary amine, which puts it in the category of ingredients that could theoretically participate in this reaction.
In practice, this risk is managed through manufacturing controls. The FDA’s guidance on nitrosamine impurities instructs manufacturers to optimize their processes to minimize or prevent nitrosamine formation, particularly by avoiding conditions where amines and nitrite salts meet under acidic conditions. The European Union takes an even stricter stance: secondary amines (a related but distinct chemical class more prone to nitrosamine formation) are prohibited in cosmetic products. These regulatory frameworks mean that finished products on the shelf have been formulated to avoid this issue, not that TEA is inherently dangerous.
You can further reduce any theoretical risk by storing products away from heat and sunlight, and by not using products that contain both TEA and nitrosating preservatives in the same formula. Most modern formulations already avoid this combination.
Will It Clog Your Pores?
Triethanolamine has a comedogenicity rating of 2 on a 0-to-5 scale in ingredient databases like CosDNA. That puts it in the low-to-moderate range, which can look concerning at first glance. But context matters here. Those databases don’t account for concentration, and pH adjusters like TEA are typically used in very small amounts. The difference between an ingredient at 0.5% and one at 15% is enormous in terms of pore-clogging potential.
Anecdotally, many people with sensitive, breakout-prone skin use TEA-containing products daily without issues. If a product breaks you out, TEA is rarely the most likely culprit compared to heavier emollients, silicones, or fragrances further up the ingredient list.
How It Compares to Other pH Adjusters
Triethanolamine isn’t the only option formulators have. Aminomethyl propanol (AMP), tromethamine, sodium hydroxide, and potassium hydroxide all serve similar pH-adjusting roles. The choice between them depends on the rest of the formula.
TEA works well in water-based and low-alcohol formulations. In products with higher alcohol content (above 50 to 60%), it starts to lose effectiveness, and alternatives like aminomethyl propanol or triisopropanolamine perform better, remaining stable in solutions with up to 80 to 90% ethanol. Sodium hydroxide, while effective in purely aqueous systems, can cause carbomer-based gels to precipitate in alcohol-containing formulas.
From your perspective as a consumer, these substitutions don’t change much about the product’s feel or safety. They’re decisions made at the formulation bench to ensure stability, and seeing any of these names on a label tells you the same thing: something is there to keep the product’s pH where it needs to be.