The material selection platform
Cosmetics Ingredients
The material selection platform
Cosmetics Ingredients


CAS Number 6440-58-0
Chem/IUPAC Name: 1,3-Bis(hydroxymethyl)-5,5-dimethylimidazolidine-2,4-dione
EINECS/ELINCS No: 229-222-8
COSING REF No: 33723
DMDM (dimethyl-dimethyl) hydantoin is an organic compound that is a member of the hydantoin family. It functions as an antimicrobial preservative by discharging formaldehyde. It is a broad-spectrum preservative that is effective against fungi, yeast, and gram-positive and gram-negative bacteria. It can be found in products like shampoos, hair conditioners, hair gels, and skin care products from the cosmetics industry.

What is DMDM HYDANTOIN used for?

DMDM hydantoin works as an antimicrobial in cosmetic and personal care products. It functions as an antibacterial agent and can aid in limiting the development of harmful bacteria, yeast, and fungi. It is a preservative that slows and prevents spoilage in items like shampoos and hair conditioners as well as in skin care items like moisturizers and foundations. It is a "formaldehyde donor," which means that over the course of a personal care product or cosmetic product's shelf life, it releases minute quantities of formaldehyde to function as a preservative and an antimicrobial.


DMDM Hydantoin is produced by reacting 3 to 5 moles of formaldehyde, as the 37% by weight aqueous solution, with 1 mole of dimethyl hydantoin at 84°C. A highly concentrated aqueous solution of the compound is prepared by reacting 2 moles of formaldehyde, as 37% formalin, with dimethyl hydantoin at 38 to 50°C, pH 8.1-8.3.

What does DMDM HYDANTOIN do in a formulation?

  • Antimicrobial
  • Preservative

Safety Profile of DMDM HYDANTOIN

The Cosmetic Ingredient Review (CIR) considers DMDM Hydantoin to be safe in the current usage levels of 0.074%. It has also been approved by the Cosmetics Directive of the European Union at a maximum concentration of 0.6%. According to the CIR safety review of this chemical, the skin does a poor job of absorbing DMDM Hydantoin. Oral exposure to DMDM Hydantoin did not have any negative effects in a laboratory study. The CIR Expert Panel noted that DMDM Hydantoin is an aqueous media formaldehyde donor. A few observations of skin irritation were made in clinical studies, and these observations may be related to the release of formaldehyde from DMDM Hydantoin. The CIR Expert Panel examined the safety of formaldehyde in cosmetics and personal care products and came to the conclusion that it was safe for the vast majority of consumers. However, it has restricted the concentration to 0.2% free formaldehyde due to some people's skin sensitivity to this agent. The amount of DMDM Hydantoin required to preserve a product (less than 1%) does not expose the consumer to concentrations of formaldehyde above the 0.2% limit for formaldehyde recommended by the CIR Expert Panel.


DMDM HYDANTOIN Technical profile

Property Values
Boiling Point 198-200°C
Melting Point 90°C
Solubility Soluble in water and ethanol

Commercial Selection : Grades containing solely DMDM HYDANTOIN

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