Custom Toner Formulation Advice

Thank you for your interest in creating a custom toner formulation. Here is some advice regarding your proposed formula and questions:

Your proposed formula is:

• Salicylic Acid (BHA) 6%
• PiteraEx 1%
• Panthenol b5 3%
• Plankton 2%
• Palmaria 5%
• Water 87%

Formulation Feedback

1. Salicylic Acid Concentration: While Salicylic Acid (BHA) is effective for exfoliation and clarifying pores, a concentration of 6% is generally too high for a leave-on cosmetic product like a toner. Regulatory limits for Salicylic Acid in leave-on skin products are typically up to 2% to ensure safety and minimize irritation. Using 6% can cause significant dryness, peeling, redness, and irritation. It is strongly recommended to reduce the Salicylic Acid concentration to 2% or less for a toner.

2. Need for Preservative: Your formula contains a high percentage of water (87%) and several ingredients like PiteraEx and Plankton, which are prone to microbial growth. Water-based formulations must contain a suitable preservative system to prevent contamination by bacteria, fungi, and yeast. Without a preservative, your toner will likely spoil quickly and could potentially cause skin infections. You cannot rely on the ingredients alone to preserve the product. You should add a broad-spectrum preservative at the manufacturer's recommended usage rate. Options like Mild Preserved Eco™ are often used in "preservative-free" claims as they are not listed as traditional preservatives by some regulations, but they still provide antimicrobial protection.

3. Palmaria Ingredient: We could not identify a specific product named "Palmaria" at a 5% usage rate in our database. Please ensure you are using a cosmetic-grade ingredient and check its recommended usage rate and compatibility.

Adding Vitamin C

You asked about adding Vitamin C. Adding L-ascorbic acid (like Vitamin C (L-ascorbic acid) (Fine)) to this formula is challenging. L-ascorbic acid is highly unstable in water and requires a low pH (ideally below 3.5 for stability, although FDA requires pH 3.5 or higher for leave-on products) to remain effective. Combining it with Salicylic Acid, which also requires a low pH to be effective, can lead to a very acidic and potentially irritating product. It also complicates the formulation process and stability.

If you wish to add Vitamin C, you might consider more stable derivatives like Ethyl Ascorbic Acid or Sodium Ascorbyl Phosphate. However, even these have specific pH requirements that may conflict with the optimal pH for Salicylic Acid, making it difficult to create a stable and effective product with both L-ascorbic acid/derivatives and Salicylic Acid at their ideal working pH ranges in the same formula.

Recommendations

For a safe and stable homemade toner:

• Reduce the Salicylic Acid concentration to a maximum of 2%.
• Add a suitable broad-spectrum preservative at the recommended concentration.
• Carefully consider the complexity and potential irritation before adding Vitamin C, especially L-ascorbic acid. If you proceed, research the specific Vitamin C derivative's pH requirements and ensure compatibility with Salicylic Acid and other ingredients.
• Confirm the identity and recommended usage of the "Palmaria" ingredient.

Always perform a small patch test before using any new cosmetic formulation on your skin.