Preservatives for Sensitive Skin and Irritation Reduction

For sensitive skin that requires a preservative, such as when not storing cosmetics in the refrigerator, Phenoxyethanol is a common choice. Here's a breakdown of your questions:

Phenoxyethanol 1%

Using Phenoxyethanol at 1% concentration can potentially cause irritation in some sensitive individuals, although it is generally considered safe for cosmetic use within the recommended range of 0.5-1.0%. The staff's suggestion to perform a patch test is a good approach to assess your personal reaction.

Regarding using less than 1%, yes, it is possible to use a lower concentration, such as 0.5%, as mentioned by the staff. The effective concentration depends on the overall formula and the required level of preservation, which should ideally be confirmed by a challenge test.

For sensitive areas like eye cream or lip balm, the recommended maximum usage rate for Phenoxyethanol is typically lower, often not exceeding 0.5% for eye products. Using it in these areas at 1% might be too high and could cause irritation. Consider using 0.5% or exploring alternative preservative blends designed for sensitive skin or specific product types.

There are different grades and blends of Phenoxyethanol available, such as Phenoxyethanol (Extra Pure) which is processed to reduce contaminants that might cause irritation, and Phenoxyethanol SA (eq. Optiphen Plus) or Chlorphenesin / Phenoxyethanol (Microcare PHC eq.) which are blends offering broad-spectrum protection, sometimes allowing for a lower concentration of Phenoxyethanol itself.

Allantoin and Bisabolol for Irritation Reduction

Both Allantoin and Bisabolol are known for their soothing and anti-irritant properties.

• Allantoin helps reduce irritation, supports skin healing by promoting new tissue growth, and strengthens the skin's resistance to allergies. It is water-soluble, but its solubility in water at room temperature is limited to about 0.5%. For better efficiency and solubility in water-based formulas like gels, it is recommended to use it with Natural Betaine.
• Natural Bisabolol (from Brazil Chamomile) or Alpha Bisabolol (synthetic) are effective in reducing skin irritation and inflammation. They are oil-soluble.

Comparing the two scenarios:

1. Allantoin 0.5% in a gel: Allantoin at 0.5% is at its solubility limit in water at room temperature. It will provide its soothing benefits within the gel base.
2. Allantoin 0.5% + Bisabolol 0.5% in a cream with oil: In a cream base that contains an oil phase, you can effectively incorporate both Allantoin (in the water phase) and Bisabolol (in the oil phase). Since both ingredients have anti-irritant properties and work through different mechanisms (Allantoin promoting tissue repair and resistance, Bisabolol reducing inflammation), using them together in a suitable base like a cream with oil is likely to provide greater irritation reduction compared to using Allantoin alone in a gel.

These ingredients can help reduce irritation caused by various factors, including preservatives and other sensitizing ingredients. The extent of irritation reduction can vary depending on the individual's skin sensitivity, the concentration of the irritant, and the overall formulation.

As the staff mentioned, combining Allantoin, Natural Betaine, and Natural Bisabolol can work synergistically to provide enhanced anti-irritant benefits. Additionally, Calendula Extract is another highly regarded ingredient for reducing sensitivity and strengthening the skin barrier.