2-Bromo-2-Nitropropane-1,3-Diol

TOO-BRO-mo-TOO-NY-tro-pro-pane-wun-three-DY-ol (BRON-oh-pol)

Preservative 3/10 Safety Not CGAvoid Synthetic Vegan

What Is 2-Bromo-2-Nitropropane-1,3-Diol?

A broad-spectrum antimicrobial preservative that also releases formaldehyde under certain conditions. Used in hair care products to prevent bacterial contamination.

Source: Synthetic organic compound

Origin: Synthetic

Also known as: Bronopol, BNP

What Does 2-Bromo-2-Nitropropane-1,3-Diol Do to Your Hair?

Provides antibacterial preservation in hair products. Can release formaldehyde when it decomposes, especially at higher pH levels or elevated temperatures. Effective against gram-negative bacteria.

Best For

None recommended

Not Recommended For

All hair types, sensitive scalp

Concentration Matters

0.01-0.1% in products

Hair Type Compatibility

1A Straight Fine
1B Straight Medium
1C Straight Coarse
2A Wavy Fine
2B Wavy Medium
2C Wavy Coarse
3A Curly Loose
3B Curly Tight
3C Curly Corkscrew
4A Coily S-Shaped
4B Coily Z-Shaped
4C Coily Tight

Method Compatibility

Curly Girl (CG) Method: Avoid
CG Avoid

Safety & Regulation

3/10
AvoidCautionSafe

Releases formaldehyde under certain conditions (high pH, heat). Can form carcinogenic nitrosamines when combined with amines. The EU allows use up to 0.1% in cosmetics with restrictions. A sensitizing allergen for many people.

FDA Status: Restricted

FDA permits use in cosmetics. EU restricts to 0.1% and prohibits use with nitrosating agents.

EWG Score: 7/10

HairAide Verdict

Another formaldehyde-releasing preservative best avoided. The potential for both formaldehyde release and nitrosamine formation makes it doubly concerning. Many safer alternatives are available.

Products That Contain 2-Bromo-2-Nitropropane-1,3-Diol

Some shampoos and rinse-off products (limited use)

Alternatives to 2-Bromo-2-Nitropropane-1,3-Diol

If you want to avoid 2-Bromo-2-Nitropropane-1,3-Diol, look for products with these ingredients instead:

Phenoxyethanol, Benzyl Alcohol, Sorbic Acid

Frequently Asked Questions

Is 2-Bromo-2-Nitropropane-1,3-Diol safe for hair?

2-Bromo-2-Nitropropane-1,3-Diol has a safety rating of 3/10 and may be problematic for many hair types. Releases formaldehyde under certain conditions (high pH, heat). Can form carcinogenic nitrosamines when combined with amines. The EU allows use up to 0.1% in cosmetics with restrictions. A sensitizing allergen for many people.

Is 2-Bromo-2-Nitropropane-1,3-Diol bad for curly hair?

2-Bromo-2-Nitropropane-1,3-Diol is not CG-method approved. Curly hair types may want to avoid this ingredient or use products containing it sparingly.

Is 2-Bromo-2-Nitropropane-1,3-Diol CG-method approved?

No, 2-Bromo-2-Nitropropane-1,3-Diol is not approved for the Curly Girl method.

What can I use instead of 2-Bromo-2-Nitropropane-1,3-Diol?

Some alternatives to 2-Bromo-2-Nitropropane-1,3-Diol include: Phenoxyethanol, Benzyl Alcohol, Sorbic Acid

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