Formaldehyde-Releasing Preservatives
dmdm hydantoin · quaternium-15 · imidazolidinyl urea
A class of preservatives that slowly release formaldehyde — a known human carcinogen (IARC Group 1) — into cosmetic formulas.
Concerns
- Formaldehyde is IARC Group 1 carcinogen
- Skin sensitization and allergic contact dermatitis
- Respiratory irritant with repeated exposure
- California Prop 65 listed
Regulatory flags
- ⚑Formaldehyde: IARC Group 1 carcinogen
- ⚑EU banned from cosmetics at >0.1% formaldehyde release
- ⚑EU requires 'contains formaldehyde' label if >0.05%
Commonly found in
Safer swaps we'd look at
Based Bodyworks
BASED Body Wash
Sulfate-free, fragrance-free body wash with no hormone-disrupting ingredients.
Why it's cleaner
No flagged ingredients in our current review; key ingredients include Coco glucoside, Aloe vera, Glycerin.
Sources & references
Last researched: April 18, 2026
Research disclaimer: This rating is based on available peer-reviewed research and regulatory assessments at the time of publication. It is not medical advice. Consult a qualified professional for personal health or skin concerns.
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