Sodium Citrate
What is Sodium Citrate?
Sodium citrate is the trisodium salt of citric acid, a naturally occurring organic acid abundant in citrus fruits such as lemons, limes, and oranges. This white, odorless, water-soluble powder has the chemical formula Na3C6H5O7. In cosmetics, it serves as a key multifunctional additive across product types including cleansers, toners, serums, moisturizers, and sunscreens. It works by donating or accepting protons to fine-tune the formulation's pH to an optimal range, ensuring compatibility with skin and ingredient stability. As a buffer, it resists pH shifts from environmental factors or ingredient interactions. By forming stable complexes with metal ions like iron or calcium, it prevents catalytic reactions that could lead to rancidity, discoloration, or reduced shelf life. It also neutralizes volatile off-notes, improving sensory appeal without strong fragrances. Derived from renewable sources, it's biodegradable and integrates seamlessly into water-based systems.
Roles in Formulation
This ingredient serves the following purposes in cosmetic formulations:
Benefits
Supports formulation stability by maintaining consistent pH levels for better ingredient performance.
Prevents metal-induced degradation, enhancing product longevity and preserving active components.
Improves user experience by minimizing unpleasant odors in multi-ingredient blends.
Who It's For
A quick guide for who this ingredient may suit (and who should be cautious).
| Who May Benefit | Who Should Avoid |
|---|---|
| Individuals preferring stable, long-lasting skincare products. | Those with confirmed allergies to citrates or citric acid derivatives. |
| Users of pH-sensitive formulations like gentle cleansers or serums. | Individuals sensitive to sodium-based compounds in cosmetics. |
| People seeking multifunctional, naturally derived stabilizers in daily routines. | People with compromised skin barriers, as patch testing is advisable. |
Safety Notes
- Rated as low hazard (EWG score 1) with no significant concerns for cosmetic use.
- Recognized as safe by cosmetic safety reviews when used within typical concentrations.
Frequently Asked Questions about Sodium Citrate
What is the main function of sodium citrate in skincare?
It adjusts and stabilizes pH, buffers against changes, chelates metals, and masks odors to enhance product performance.
Is sodium citrate safe for sensitive skin?
Yes, it has a low hazard rating and is generally well-tolerated, with minimal irritation potential.
Where does sodium citrate come from?
It derives from citric acid naturally present in citrus fruits, processed into a sodium salt for cosmetic use.