1,3-Propanediol, 1 l

1,3-Propanediol is a glycol obtained by fermentation of renewable raw materials followed by distillation. In a formulation, it binds water as a humectant and also serves as a solvent for water-soluble active ingredients and botanical extracts. In natural cosmetics, it replaces petrochemical propylene glycol in the same function and meets the requirements of the COSMOS Approved and NATRUE Approved certifications.

It mixes with water, alcohol, and other glycols. Suitable for both rinse-off and leave-on products for the face, body, hair, and scalp.

Key benefits

• Skin hydration – according to corneometric measurements by the manufacturer, it increases skin hydration more significantly than placebo and, in the same test, more than 1,3-butanediol and propylene glycol.
• Solvent – dissolves and carries water-soluble active ingredients and botanical extracts, facilitating their incorporation into the water phase.
• Preservation support – in the manufacturer's test, a serum with 0.8% Phenethyl Alcohol at pH 6.5 failed the preservation challenge test; after adding 5% 1,3-Propanediol, it achieved grade A per ISO. It is not a preservative itself, but it supports the effectiveness of the preservation system.
• Renewable origin – produced by fermentation with a non-pathogenic strain, GMO-free and palm oil-free, readily biodegradable (OECD 301).

Use in formulation

1,3-Propanediol belongs in the water phase. The recommended dosage is 1 – 50%. To support preservation, the manufacturer used 5% in their test; higher percentages are used when dissolving larger amounts of extracts or in products where the glycol forms a substantial part of the base.

Active ingredients and extracts that are less readily soluble in water are best first dispersed in 1,3-Propanediol and then blended into the water phase. There are no compatibility restrictions; it is compatible with common emulsifiers, thickeners, and preservatives.

Suitable for products such as

• Facial serums and tonics – humectant and carrier of active ingredients in leave-on products.
• Creams and lotions – in the water phase of O/W emulsions for hydration and preservation support.
• Shampoos and hair masks – hydrating ingredient for hair and scalp in rinse-off products.
• Gels and hydrating masks – dissolves extracts and active ingredients in a water base.
• Body care products – suitable for dry and sensitive skin, making it appropriate for full-body products.

What is good to know

The raw material contains at least 99.8% 1,3-propanediol. The substance is not classified as hazardous under the CLP Regulation, so a safety data sheet is not required. It contains no fragrance allergens, parabens, or ingredients of animal origin, and according to the manufacturer it has not been tested on animals. Ethylene oxide is not used in its production.

It is not suitable for anhydrous products such as oil serums and balms. It does not dissolve in oils, and its moisturising effect only applies in products containing water.

Frequently asked questions