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%
