What is it?
A chelating agent made from monosodium glutamate, the sodium salt of the amino acid glutamic acid. Chelating agents bind trace metals, such as calcium, magnesium and iron, that can make products less stable or reduce lather in hard water. It is used mostly in soaps and cleansers, and also in deodorants, hair sprays, eye makeup and some household cleaners. It is one of the newer, biodegradable alternatives to EDTA.
Key information
- The CIR Expert Panel concluded in 2025 that tetrasodium glutamate diacetate is safe in cosmetics in the present practices of use and concentration.
- It was reported in 752 cosmetic products, mostly bath soaps and cleansers, at up to 1 percent.
- It did not cause allergic reactions in a guinea pig test or in a 104-person patch test of an eyeliner containing it.
- It is one of several newer chelating agents studied as biodegradable replacements for EDTA.
More information
Tetrasodium glutamate diacetate, often shortened to GLDA, is made by attaching two acetate groups to monosodium glutamate. The Cosmetic Ingredient Review (CIR) report describes two commercial routes: one reacts monosodium glutamate with monochloroacetic acid, and the other reacts it with hydrogen cyanide and formaldehyde, followed by treatment with sodium hydroxide. It is supplied as a water-based solution.
The CIR Expert Panel assessed it in a report published in 2025 and concluded that it is safe in cosmetics in the present practices of use and concentration. In 2021 FDA data it appeared in 752 products, most of them bath soaps and detergents, at up to 1 percent. Animal studies showed low toxicity and little absorption from the gut. It was rated non-irritating to rabbit eyes, and it did not cause allergic reactions in a guinea pig test or in a patch test of 104 people using an eyeliner that contained it.
One supplier’s material contained a trace impurity, 0.15 percent of the sodium salt of nitrilotriacetic acid, which the International Agency for Research on Cancer classifies as possibly carcinogenic to humans (Group 2B). The panel considered this and was not concerned, because genotoxicity tests on the ingredient were negative and leave-on use levels are low.
Older chelating agents such as EDTA and DTPA do not biodegrade and build up in waterways, and GLDA is among the newer alternatives studied to replace them. On ingredient lists it appears as tetrasodium glutamate diacetate. See also our profiles for pentasodium pentetate and tetrasodium etidronate.
Sources: Cosmetic Ingredient Review: Safety assessment of tetrasodium glutamate diacetate and beta-alanine diacetic acid as used in cosmetics (International Journal of Toxicology, 2025); European Commission CosIng: Tetrasodium Glutamate Diacetate; Environmental Science and Pollution Research (2014): Biodegradable chelating agents for industrial, domestic, and agricultural applications, a review
