Very Disliked

Diazolidinyl Urea

Explained

Diazolidinyl Urea is an antimicrobial preservative. It is commonly used to prevent bacterial, yeast, and mold growth.

Why is it controversial?

Diazolidinyl Urea slowly breaks down into formaldehyde, an effective microbe killer but also a known allergen/carcinogen.

Some people who are allergic to imidazolidinyl urea also react to diazolidinyl urea. It ranked as the 14th most common allergen in patch tests from 2005–06.

Safety reviews show that at concentrations under 0.5%, the formaldehyde released remains below the accepted safety limit, making it considered safe for cosmetic use.

Ultimately, its safety depends on individual skin sensitivity and personal comfort with formaldehyde-releasing preservatives.

See all 594 products with Diazolidinyl Urea

Users who like it
5%
Users who avoid it
95%

What it does

Preservative Tending to preserve or capable of preserving.

Prevalence

Less common Percentage of products that contain it
0.6%
Top categories
Moisturizers
Cleansers
Treatments
Position Predominant list placement
Bottom 50%
Concentration Concentrations we've seen
0%

References

CosIng Data

CosIng ID 33218
INCI Name DIAZOLIDINYL UREA
EC #  278-928-2
All Functions Preservative