Imidazolidinyl Urea

Imidazolidinyl Urea 1
molecular structure · PubChem CID 38258
AKA: IMIDUREA, 39236-46-9, Germall 115, Methanebis(N, N'-(5-ureido-2, 4-diketotetrahydroimidazole)-N, N-dimethylol), N''-Methylenebis(N'-(1-(hydroxymethyl)-2, 5-dioxo-4-imidazolidinyl)urea), CHEBI:51805
Synthetic
Preservative
Not Clean
N,N'-Methylenebis[N'-[3-(hydroxymethyl)-2,5-dioxoimidazolidin-4-yl]urea]
Formula
C11H16N8O8
Mol. Weight
388.29
CAS #
39236-46-9
Form
Powder
State
Exists as the monohydrate: White odorless solid; [Merck Index]
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Caution
Allergen Warning
⚠️ Formaldehyde Releaser
Functions
Preservative
Keeps your product from growing bacteria, mold, or yeast. Without these, that jar of cream becomes a petri dish in about a week.
Anti-Inflammatory
Moisturizing
Boosts Collagen
Prevents microbial growth
The paper trail
🔬Peer-reviewed1 paper →
⚖️Regulatory1 listing →
🛡️Safety-assessed2 reviews →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
EWG
4
CIR
Reviewed by CIR
Pregnancy
Caution
CIR Safety Findings
Not Phototoxic
Animal test and Product formulation test found no phototoxicity in the CIR safety assessment (CIR 254)
Mixed Eye Irritation Results
4 studies / 1 irritating / 3 not irritating / reactions mild (CIR 254)
Mixed Skin Irritation Results
11 studies / 1 irritating / 1 mixed / 9 not irritating / reactions slight to severe (CIR 254)
Mixed Sensitization Results
7 studies / 1 mixed / 6 not sensitizing / plus 5 case reports (CIR 254)
Concentration Guide
Leave-on0.0002–0.6%
Rinse-off0.0000004–0.5%
0%50%100%
Reg. limit 0.6%
CIR reported use · 2018 survey
EU regulatory limit: 0.6%. Source: EU Cosmetics Regulation (EC) 1223/2009, Annex V (Preservatives), Entry 27.
Regulatory Status
USAunder review
EU✔ permitted
JAPAN✔ permitted
CANADA✔ permitted
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR