It may be largely synthetically derived these days, but potassium sorbate is a naturally occurring component of berries and should be safe to use for all except those with highly sensitive skin – as long as its concentration level is kept in check.
Systematic Name: Potassium (2E,4E)-hexa-2,4-dienoate
Also listed as: Sorbistat potassium; Sorbistat-K; potassium salt; 2,4-hexadienoic acid; 2-4 hexadienoic acid, potassium salt; potassium 2,4-hexadienoate; E202.
Definition: Potassium sorbate is the potassium salt of sorbic acid, an unsaturated fatty acid which is mainly used as a food preservative. Sorbic acid is a white crystalline powder that occurs naturally in the berries of the mountain ash tree; however, most of the world’s sorbic acid production is derived synthetically.
Both potassium sorbate and sorbic acid have anti-fungal, antimicrobial and preservative properties. They are not as effective against bacteria, however.
Potassium sorbate and sorbic acid are widely used in cosmetics, especially organic/natural cosmetics, because their preservative properties prevent the formulas from spoiling, thereby extending shelf-life. Potassium sorbate is considered a safe alternative to parabens; it is non-irritating, non-sensitizing and non-mutagenic. Even its long-term internal usage has shown no side-effects.
In the cosmetic industry, potassium sorbate is found in: cleanser, toner, moisturizer, exfoliant, loose powder, foundation, blush, eye makeup, body wash, body lotion, sunscreen, and shampoo.
- Limited evidence of non-reproductive system toxicity;
- Data gaps: more studies have yet to be conducted to assess its safety.
Our Rating: Good.
Warning: sorbic acid could cause dermatitis at concentrations of 0.5 % or higher.
Ishtar Magally Mobarak