Formaldehyde
INCI: FORMALDEHYDE
Also known as: Formalin, Methanal
Key Facts
- CAS Number
- 50-00-0
- Category
- preservative
- Risk Level
- high
- Common Allergen
- Yes
- EU Status
- Restricted
- Max Concentration
- 0.1% (free formaldehyde)
- Found In
- nail polish, hair straightening
Is Formaldehyde safe in cosmetics?
Formaldehyde is rated high risk in cosmetic products. It is a known allergen that can cause contact dermatitis in sensitized individuals. Strong sensitizer and classified carcinogen (IARC Group 1). This ingredient is restricted under EU cosmetic regulations. Safer alternatives include Phenoxyethanol, Sodium Benzoate, Potassium Sorbate. Commonly found in nail polish, hair straightening.
What is Formaldehyde?
Known carcinogen and potent allergen. Rarely used directly but released by formaldehyde-releasing preservatives.
Allergy & Safety Information
Formaldehyde is classified as a high-risk ingredient. It is a known cause of allergic contact dermatitis. It is restricted or regulated in the EU. Individuals with sensitive skin or a history of contact allergies should avoid products containing this ingredient. A patch test is recommended before first use of any product containing Formaldehyde.
Cross-Reactions
If you react to Formaldehyde, you may also react to:
Safer Alternatives
These ingredients serve a similar function with lower allergy risk:
Frequently Asked Questions
Is Formaldehyde safe for sensitive skin?
Formaldehyde is a known allergen and is generally not recommended for sensitive skin. Consider patch testing before use.
What products contain Formaldehyde?
Formaldehyde is commonly found in nail polish, hair straightening.
What does Formaldehyde do in cosmetics?
Formaldehyde functions as a preservative in formulations. Strong sensitizer and classified carcinogen (IARC Group 1).
Related Guides
Top 10 Cosmetic Allergens
Is Formaldehyde on the list? See the full clinical ranking.
Preservative Allergy Guide
Which preservatives cause the most reactions and what to use instead.
How to Read Ingredient Labels
Decode INCI names and find hidden allergens in your products.
Find Your Skin Allergy Trigger
Step-by-step elimination method to identify your trigger.
Contact Dermatitis Guide
Symptoms, causes, patch testing, and treatment options.
Is Formaldehyde causing YOUR skin reactions?
SkinDetekt tracks your products and reactions to find your personal triggers. Download the app to find out.
Download on App Store