Topical therapeutic corneal and scleral tissue cross-linking solutions: in vitro formaldehyde release studies using cosmetic preservatives.
Takaoka A, Cao K, Oste EM, Nagasaki T, Paik DC.
Biosci Rep. 2019 May 3;39(5). pii: BSR20182392. doi: 10.1042/BSR20182392. Print 2019 May 31.

Contact Dermatitis to Medications and Skin Products.
Nguyen HL, Yiannias JA.
Clin Rev Allergy Immunol. 2019 Feb;56(1):41-59. doi: 10.1007/s12016-018-8705-0. Review.

Preservatives as important etiologic factors of allergic contact dermatitis.
Kręcisz B, Chomiczewska-Skóra D, Kieć-Świerczyńska M.
Med Pr. 2015;66(3):327-32. doi: 10.13075/mp.5893.00176.

Cosmetic preservatives as therapeutic corneal and scleral tissue cross-linking agents.
Babar N, Kim M, Cao K, Shimizu Y, Kim SY, Takaoka A, Trokel SL, Paik DC.
Invest Ophthalmol Vis Sci. 2015 Jan 29;56(2):1274-82. doi: 10.1167/iovs.14-16035.

Sensitivity of petrolatum and aqueous vehicles for detecting allergy to imidazolidinylurea, diazolidinylurea, and DMDM hydantoin: a retrospective analysis from the North American Contact Dermatitis Group.
Rietschel RL, Warshaw EM, Sasseville D, Fowler JF Jr, DeLeo VA, Belsito DV, Taylor JS, Storrs FJ, Mathias CG, Maibach HI, Marks JG Jr, Zug KA, Pratt M; North American Contact Dermatitis Group.
Dermatitis. 2007 Sep;18(3):155-62.

Contact allergy from DMDM hydantoin, 1994-2000.
Uter W, Frosch PJ; IVDK Study Group and the German Contact Dermatitis Research Group, DKG.
Contact Dermatitis. 2002 Jul;47(1):57-8.

DMDM hydantoin is used as a bactericide and preservative in many cosmetic products, but it is a component registered in the FAR register of "releasers formaldehyde", ie of those chemical products that release formaldehyde. Regarding toxicity, the level was ascertained from 0.001 to 0.1 mM on human skin (1).

On a sample of 4,238 patients tested with the patch-test, positive allergic reactions for DMDM Hydantoin were 1.6% (2):

• Formaldehyde 6.6%
• Quaternium-15 6.4%
• Methylchloroisothiazolinone / methylisothiazolinone 5%
• Lanolin alcohol 4.6%
• Cinnamic aldehyde 3.9%
• Diazolidinyl urea 2.1%
• Imidazolidinyl urea 1.6%
• Bronopol 1.6%
• Glutaral 1.5%
• Parabens mixed 1.4%

References______________________________

(1) Cosmetic preservatives as therapeutic corneal and scleral tissue cross-linking agents.
Babar N, Kim M, Cao K, Shimizu Y, Kim SY, Takaoka A, Trokel SL, Paik DC.
nvest Ophthalmol Vis Sci. 2015 Jan 29;56(2):1274-82. doi: 10.1167/iovs.14-16035.
(2) North American contact dermatitis group patch test results: 2011-2012.
Warshaw EM, Maibach HI, Taylor JS, Sasseville D, DeKoven JG, Zirwas MJ, Fransway AF, Mathias CG, Zug KA, DeLeo VA, Fowler JF Jr, Marks JG, Pratt MD, Storrs FJ, Belsito DV.
Dermatitis. 2015 Jan-Feb;26(1):49-59. doi: 10.1097/DER.0000000000000097.

DMDM Hydantoin is a chemical compound,  preservative and antibacterial.

The name defines the structure of the molecule

• "DMDM" is an acronym derived from the chemical structure of the compound, specifically "Dimethylol Dimethyl".
• "Hydantoin" is an organic compound derived from urea. It has a cyclic structure and can act as a preservative.

Description of raw materials used in production

• Dimethylolurea - A chemical used as a starting point in the production of DMDM Hydantoin.
• Formaldehyde - A chemical used to derivatize dimethylolurea to form DMDM Hydantoin.

Step-by-step summary of industrial chemical synthesis process.

• Combination of Reagents - Dimethylolurea and formaldehyde are combined in a reactor under controlled conditions.
• Heating - The mixture is heated to facilitate the reaction between dimethylolurea and formaldehyde.
• Monitoring the Reaction - The formation of DMDM Hydantoin is monitored through various techniques like chromatography.
• Purification - Once the reaction is complete, the product is purified to remove any impurities and unreacted substances.
• Drying - Moisture is removed from the product.
• Quality Control - The final product undergoes various quality checks to ensure it meets specifications.

It is used in:

• cosmetics
• personal care products
• industry: cutting oils

In the course of the studies and the use of this product, it was discovered that it releases formaldehyde

Cosmetics

Preservative. Any product containing organic, inorganic compounds, water, needs to be preserved from microbial contamination. Preservatives act against the development of harmful microorganisms and against oxidation of the product.

(DMDM Hydantoin and formaldehyde )

so that in all the products that use it the chemical risk must be indicated.

DMDM Hydantoin studies

Molecular Formula: C₇H₁₂N₂O₄

Molecular Weight: 188.183 g/mol

UNII: BYR0546TOW

CAS: 6440-58-0

EC Number: 229-222-8

Synonyms:

• 1,3-Bis(hydroxymethyl)-5,5-dimethylimidazolidine-2,4-dione
• Dmdmh
• Glydant
• Dimethyloldimethyl hydantoin
• 2,4-Imidazolidinedione, 1,3-bis(hydroxymethyl)-5,5-dimethyl-
• 1,3-Bis(hydroxymethyl)-5,5-dimethyl-2,4-imidazolidinedione
• 1,3-dimethylol-5,5-dimethyl hydantoin
• bis(hydroxymethyl)-5,5-dimethylhydantoin
• Bis(hydroxymethyl)-5,5-dimethyl-2,4-imidazolidinedione
• 1,3-bis(hydroxymethyl)-5,5-dimethyl-imidazolidine-2,4-dione
• SCHEMBL69185
• 1,3-Di(hydroxymethyl)-5,5-dimethylhydantoin
• AK114999
• dimethylol dimethyl hydantoin
• 1,3-Dihydroxylmethyl-5,5-dimethylhydantoin
• Hydantoin, 1,3-bis(hydroxymethyl)-5,5-dimethyl-
• W-104844
• 1,3-bis(hydroxymethyl)-5,5-dimethyl-1,3-diazolidine-2,4-dione
• 1,3-Dimethylol-5,5-dimethylhydantoin
• 1,3-Bis(hydroxymethyl)-5,5-dimethylhydantoin
• Dantoin-DMDMH
• Glycoserve-DMDMH
• Dantoin dmdmh 55
• Dmdmh 55
• Caswell No. 273AB
• Dimethylol-5,5-dimethylhydantoin
• dimethyloldimethylhydantoin