Isopropylparaben
molecular structure · PubChem
AKA: Isopropyl 4-hydroxybenzoate, 4191-73-5, Isopropyl p-hydroxybenzoate, P-Hydroxybenzoic acid isopropyl ester, Benzoic acid, 1-methylethyl ester, 1-Methylethyl-4-hydroxybenzoate, 4-Hydroxybenzoic acid
Synthetic
Preservative
Not Clean
The CIR Expert Panel concluded that the following 20 parabens are safe in cosmetics in the present practices of use and concentration described in the safety assessment when the sum of the combined concentration of parabens in any given formulation does not exceed 0.8 %...Isopropylparaben...
Formula
C10H12O3
Mol. Weight
180.20
CAS #
4191-73-5
Form
Powder
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.
Preserves Formula
Reduces Inflammation
Fights Bacteria
UV Protection
Prevents microbial growth
Traditional Use
Synthetic preservative developed in the early 20th century as part of the paraben family. Created to replace earlier antimicrobial agents like phenol and mercury compounds with safer, more effective alternatives for extending cosmetic shelf life.
EWG
10
CIR
Safe as used
Pregnancy
Yes
Restricted By
CIR Safety Findings
medical-approval
all-shades-safe
Phototoxicity Concern
Concentration Guide
8.0%
0%11%
Reg. Limit
EU regulatory limit: 8.0%. 0,4% (as acid) for single ester 0,8% (as acid) for mixtures of esters Source: EU Cosmetics Regulation (EC) 1223/2009, Annex V (Preservatives), Entry 12. Dermal absorption: 0.1%. Source: CIR Safety Assessment (CIR Seq 746).
Regulatory Agencies
🧂Conflict of interest.
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
The paper trail
🔬Peer-reviewednone on file
⚖️Regulatory1 listing →
🛡️Safety-assessed3 reviews →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
Verified Jun 2026 · 🧪 = conflict
Data: PubChem · CosIng · EWG · CIR