Propylparaben

Propylparaben (CAS 94-13-3) is a synthetic preservative approved as E216 across food, cosmetic, and pharmaceutical applications. Also marketed as Tegosept P, Solbrol P, and Protaben P.

Where is Propylparaben used?

• Personal care and cosmetics: preserves lotions, shampoos, and creams against microbial contamination throughout shelf life
• Pharmaceuticals: preservative in oral suspensions, topical preparations, and multi-dose injectable formulations where microbial control is a strict regulatory requirement
• Food and beverage: protects baked goods, sauces, and beverages under the E216 designation
• Coatings and adhesives: biocide preventing microbial degradation during storage and application
• It inhibits the growth of mold, yeast, and bacteria at low concentrations.
• Dissolves easily in lipophilic components and can be incorporated into a formulation by adding it to the oil phase with some heating before any emulsification step.

Good to know: Often used in combination with methylparaben for broader efficacy and protection.

Formulation notes

• Antimicrobial activity is significantly reduced in the presence of nonionic surfactants as a result of micellization.
• Absorption by plastics has been reported, the amount absorbed depending on the type of plastic and the vehicle.
• Discolors in the presence of iron and is subject to hydrolysis by weak alkalis and strong acids.

Typical specification

• Typical assay is at least 99.0% by HPLC.
• Loss on drying is typically ≤0.5%.
• Standard particle size is 80 mesh.
• Slightly soluble in water.
• Available in grades such as BP, USP, EP, FCC, NF, JP, and as a certified reference material (TraceCERT) and USP reference standard.

Regulatory status

• The maximum concentration of propylparaben and its sodium and potassium salts in ready-to-use cosmetics in the EU, expressed as acid, is 0.14% for the sum of individual concentrations.
• Propylparaben, sodium propylparaben and potassium propylparaben are listed under entry 12a of Annex V to the EU cosmetics regulation.
• Mixtures of substances are permitted up to 0.8% provided the sum of individual concentrations of propylparaben and butylparaben and their salts does not exceed 0.14%.
• The presence of parabens in medicines must be indicated due to their allergenic potential, according to the European Commission guideline CPMP/463/00Rev.1.

Storage, packaging and handling

• Aqueous solutions at pH 3–6 can be sterilized by autoclaving without decomposition.

Frequently asked questions about Propylparaben

What is the regulatory status of propylparaben as a food additive in the EU?

In the EU, E216 and E217 are no longer permitted as food additives.

Are there restrictions on the use of propylparaben in cosmetic products for young children in the EU?

Propylparaben must not be used in leave-on cosmetic products intended for application on the nappy area of children under three years of age.

What labelling requirements apply to leave-on cosmetics containing propylparaben for children under three?

Leave-on cosmetics intended for children under three years, even if not specifically proposed for nappy change use, must carry the label warning 'Do not use in the nappy area' if they contain propylparaben and related preservatives.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.