What Is Tetrasodium Hydroxy Iminodisuccinate?
Tetrasodium Hydroxy Iminodisuccinate is a salt derived from aspartic acid, an amino acid that occurs naturally in plants and animals. Although the finished ingredient is made in a lab, many manufacturers start with plant based sugars that are fermented and then transformed through a series of safe chemical steps. The result is a white, water soluble powder that works as a chelating agent. This ingredient was developed in the 1990s as a more eco friendly option to older chelators like EDTA, which can linger in the environment. Over the years it has gained popularity in cosmetics because it is readily biodegradable and gentle on skin.
The production process involves reacting aspartic acid with other simple organic compounds, followed by neutralizing the mixture with sodium salts. Careful purification removes unwanted by-products, giving a high purity powder that dissolves easily in water based formulas.
You will most often find Tetrasodium Hydroxy Iminodisuccinate in cleansers, shampoos, conditioners, face masks, serums, moisturizers, sunscreens, anti aging creams and even color cosmetics like foundations or liquid blushes. Brands use it to keep products looking clear and stable over time.
Tetrasodium Hydroxy Iminodisuccinate’s Cosmetic Benefits/Uses
This ingredient plays one main role in skin and hair care formulas.
Chelating: It grabs onto trace metals such as iron, copper and calcium that sneak into a product through water, pigments or packaging. By locking these metals up it stops them from messing with preservatives, changing a product’s color or breaking down key actives. A good chelator helps a cleanser foam better, keeps a cream from turning yellow and lets fragrances stay true. In short it keeps products looking, feeling and smelling fresh for longer, which means you get the full benefit of every other ingredient.
Who Can Use Tetrasodium Hydroxy Iminodisuccinate
Tetrasodium Hydroxy Iminodisuccinate is considered suitable for all skin types including sensitive, oily, combination and dry because it does not leave a film, clog pores or change the skin’s natural pH. It stays on the surface of the skin and hair to do its job so it is unlikely to trigger issues specific to any one skin type.
The ingredient is made from plant derived raw materials and contains no animal by products which makes it appropriate for both vegans and vegetarians. Manufacturers often highlight this when formulating clean or cruelty free lines.
Current safety reviews show no evidence that the ingredient poses a risk during pregnancy or while nursing. This is not medical advice and anyone who is pregnant or breastfeeding should still check with a doctor before adding new products to a routine
Tetrasodium Hydroxy Iminodisuccinate does not make skin more sensitive to the sun and does not interact with UV filters so there is no special need for extra sun precautions beyond daily SPF use.
Potential Side Effects/Adverse Reactions
Reactions to any cosmetic ingredient can differ from person to person. The points below outline potential side effects of topical Tetrasodium Hydroxy Iminodisuccinate though most users will never encounter them when the ingredient is used correctly in a finished product.
- Mild skin irritation small numbers of people may notice temporary redness or itching, usually when the product sits on the skin for a long time without rinsing
- Allergic contact dermatitis extremely rare cases of allergy have been reported with chelators and may show up as a rash or hives
- Eye irritation if a high concentration accidentally gets into the eyes it can cause stinging or watering until rinsed out
- Dryness very sensitive or compromised skin may feel a bit tight if exposed to a leave on formula with a higher percentage of the ingredient
If you experience any of these effects stop using the product and seek guidance from a healthcare professional
Comedogenic Rating
Rating: 0/5
Tetrasodium Hydroxy Iminodisuccinate is fully water soluble and used at very low levels, so it rinses away without leaving an oily film that could block pores. It does not interact with skin sebum and has no history of causing bumps or blackheads, which is why it earns a solid zero on the comedogenic scale. This makes it suitable for people who are prone to acne or frequent breakouts.
The ingredient is usually added to formulas at less than 1 percent, further reducing any chance of pore clogging. Because it is a chelating agent rather than an emollient or thickener, it stays dissolved in the water phase and never sits inside pores. No additional concerns related to comedogenicity have been noted in industry or scientific reports.
Summary
Tetrasodium Hydroxy Iminodisuccinate is mainly a chelating agent that grabs stray metal ions like iron, copper and calcium. By binding these metals it keeps preservatives working, colors from shifting and active ingredients from breaking down, so products stay clear stable and effective for longer.
The ingredient has been gaining traction as a greener alternative to EDTA but it is still less common in older mass market formulas. Niche clean beauty brands and large companies focused on sustainability are driving its rising popularity.
Current research shows it is low risk for skin and eye irritation, non sensitizing and readily biodegradable. While it is considered safe for most users, trying any new product on a small patch of skin first is always a smart step.