Sodium Castorate

What is Sodium Castorate?

Sodium Castorate is the sodium salt of fatty acids from castor oil, sourced from the seeds of Ricinus communis, a plant native to tropical regions. The oil undergoes hydrolysis to break down into fatty acids, primarily ricinoleic acid, which are then neutralized with sodium hydroxide to form this soap-like compound. In cosmetics, it appears mainly in rinse-off products such as bar soaps, liquid hand soaps, shampoos, and body washes. As an anionic surfactant, it reduces surface tension between water and oils, enabling the formation of micelles that trap dirt and sebum for easy rinsing. Its emulsifying properties help blend oil and water phases, contributing to stable, foamy formulations without harsh synthetic detergents.

Comedogenic Rating 0/5 Low risk of clogging pores
EWG Safety Rating 1 View on EWG →

Roles in Formulation

This ingredient serves the following purposes in cosmetic formulations:

Surfactant
Lowers surface tension to enable cleansing, emulsifying, and foaming; central to shampoos, body washes, and many emulsions and micellar systems.
Cleansing agent
Removes dirt, oil, and impurities by lowering surface tension and forming micelles, enabling soils to be lifted and rinsed away from skin, hair, or teeth.
Emulsifying agent
Enables stable mixing of oil and water phases by forming an interfacial film, helping create lotions, creams, and cleansers with consistent texture.

Benefits

Supports effective removal of dirt and excess oils through micelle formation.

Helps create stable emulsions in cleansers for smooth texture.

Derived from renewable plant sources, offering a biodegradable cleansing option.

Who It's For

A quick guide for who this ingredient may suit (and who should be cautious).

Who May Benefit Who Should Avoid
People preferring plant-based ingredients in daily cleansers.
Those with known allergies to castor oil or its derivatives.
Individuals using mild soap formulations for routine hygiene.
People experiencing contact dermatitis from soap bases.
Users of natural shampoos and body washes seeking foaming action.
Individuals sensitive to alkaline surfactants in high concentrations.

Safety Notes

  • Rated low hazard by environmental health assessments.
  • Non-comedogenic, unlikely to clog pores in rinse-off uses.

Frequently Asked Questions about Sodium Castorate

What is Sodium Castorate made from?

It comes from the fatty acids of castor oil (Ricinus communis seeds), processed into a sodium salt for use as a cleanser.

Is it safe for sensitive skin?

It shows low irritation in reviews from cosmetic safety panels, suitable for many in rinse-off products.

What products contain it?

Commonly found in natural bar soaps, liquid soaps, shampoos, and foaming body washes.