Formulation Review

Your proposed formula includes:

• MSH Black™ (Acetyl Hexapeptide-1) 5%
• GreyReverse™ (Palmitoyl Tetrapeptide-20) 5%
• Panthenol (Pro Vitamin B5, DL- Panthenol, Powder) 3%
• Pure Keratin™ (Natural, Australian Sheep Wool) 2%
• Water 84%
• Preservative 1%

The total percentage is 100%, which is correct. The concentrations of the active ingredients MSH Black™ (5%) and GreyReverse™ (5%) are within the recommended usage rates for reducing gray hair in a spray format. Pure Keratin™ (2%) is also within the recommended range for leave-on hair treatments.

Regarding Panthenol, 3% is a common and effective concentration for hair products. Please note that our search found information on PreB5™ (Pantolactone), which is a precursor to Vitamin B5, with a lower recommended usage rate (0.5-1%). Ensure you are using the correct form of Panthenol (DL-Panthenol) as intended, and verify its specific recommended usage rate if it is a different product.

Important Consideration for Spray Format

Based on the product information for MSH Black™, it is advised not to use this ingredient in a spray format. This is because it stimulates melanin production and can cause unintended darkening on skin areas where the spray mist lands. For a product specifically targeting hair, a different application method (like a serum or lotion applied directly to the scalp) might be more suitable to avoid this issue.

Preservative Recommendation

For a water-based formula like a hair spray, a broad-spectrum preservative is essential to prevent microbial growth. You can use a preservative at a concentration of around 1%, as you have allocated in your formula.

Some suitable preservatives for this type of product include:

• Phenoxyethanol P5: A widely used broad-spectrum preservative effective against bacteria, yeast, and mold.
• Preserve-BSB™ (eq. Optiphen BSB-W): Another effective broad-spectrum preservative option.

Always follow the supplier's recommended usage rate for the specific preservative you choose, as it may vary slightly.

Conclusion

The concentrations of your active ingredients (MSH Black™, GreyReverse™, and Pure Keratin™) are appropriate for their intended effects in a hair treatment. However, the use of MSH Black™ in a spray format is not recommended due to the risk of skin darkening. You may want to consider an alternative application method or adjust the formulation based on this. You will definitely need a suitable preservative like Phenoxyethanol P5 or Preserve-BSB™ at approximately 1% to ensure the stability and safety of the water-based product.