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2-Bromo-2-Nitropropane-1,3-Diol
AKA “bronopol, 3-propanediol, Bronosol, Bronocot, Bronotak, Bronidiol, Bronopolu, Lexgard bronopol”
Synthetic
Ingredient Facts
2-Bromo-2-Nitropropane-1,3-Diol
AKA: Bronopol, 3-propanediol, Bronosol, Bronocot, Bronotak, Bronidiol, Bronopolu, Lexgard bronopol
Synthetic · Antimicrobial · EWG: 7
Synthetic
Preservative
Synthetic
Not Clean
Helps preserve the product and keep it fresh longer, preventing the growth of unwanted bacteria and mold.
Solubility greater than or equal to 100 mg/mL at 63 °F (NTP, 1992)
Formula
C3H6BrNO4
Mol. Weight
199.99
CAS #
52-51-7
Form
Powder
State
2-bromo-2-nitropropane-1,3-diol appears as white crystals. Ignite easily and burn readily. May detonate under strong shock. Decomposes when heated, evolving toxic gases. Toxic by skin absorption, inha
See origin →
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.
Antimicrobial
Keeps your product from growing bacteria, mold, or yeast. Without these, that jar of cream becomes a petri dish in about a week.
Preserves Formula
Fights Bacteria
Locks In Moisture
Wound Healing
Prevents microbial growth
Traditional Use
A synthetic preservative developed in the mid-20th century for cosmetics and personal care products. It was designed to provide broad-spectrum antimicrobial activity and replace older, less effective preservatives.
Skin Types
●all-skin-types
Best For
General
Melanin-Rich Skin
Suitable
Pregnancy & Breastfeeding Safe
Caution
EWG
7
CIR
Safe w/Qualifications
Pregnancy
Caution
CIR Safety Findings
Not a Sensitizer
ewg-7
medical-approval
all-shades-safe
Concentration Guide
0.1%
0%0%
Reg. Limit
EU regulatory limit: 0.1%. Source: EU Cosmetics Regulation (EC) 1223/2009, Annex V (Preservatives), Entry 21.
Regulatory Status
USA✔ permitted
EU✔ permitted
JAPAN✔ permitted
CANADA✔ permitted
🧂Conflict of interest.
Addendum to the Final Report on the Safety Assessment of 2-Bromo-2-Nitropropane-1,3-Diol (JEPT 4(4) 47-61 1980)
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
→
Final Report of the Safety Assessment for 2-Bromo-2-Nitropropane-1,3-Diol
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
→
Revised Tentative Report: Amended Safety Assessment of 2-Bromo-2-Nitropropane-1,3-Diol as Used in Cosmetics
Cosmetic Ingredient Review (CIR) Expert Panel
International Journal of Toxicology
→
2-Bromo-2-Nitropropane-1,3-Diol
European Commission
EU Cosmetic Ingredient Database (CosIng)
→
2-Bromo-2-Nitropropane-1,3-Diol
Environmental Working Group (EWG)
EWG Skin Deep Cosmetics Database
→
2-Bromo-2-nitropropane-1,3-diol
Health Canada
Health Canada Cosmetic Ingredient Hotlist
→
Progress in 1,3-propanediol biosynthesis.
Li B, Gao W, Pan Y, Yao Y, Liu G
Frontiers in bioengineering and biotechnology, 2024
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Effects of 1,3-propanediol associated, or not, with butylene glycol and/or glycerol on skin hydration and skin barrier function.
Pinto JR, Monteiro E Silva SA, Leonardi GR
International journal of cosmetic science, 2024
→
Verified Feb 2026 · 🧪 = conflict
Data: PubChem · CosIng · EWG · CIR