Preservatives in Mascara Formulation

Yes, it is absolutely essential to include a preservative in your mascara formula, especially for products used around the eyes. Mascara is highly susceptible to microbial contamination, which can pose a safety risk to the user and shorten the product's shelf life. Preservatives prevent the growth of bacteria, mold, and yeast, ensuring product safety and longevity.

Based on the search, several preservatives are suitable for eye area products. Here are a few options:

• Eye Preserved™ (Polyhexamethylene Biguanide, PHMB): Specifically designed for contact lens solutions, making it very gentle and suitable for eye area or sensitive skin products. It is heat resistant, water-soluble, and effective in the pH range of 3-8 (recommended 3-6.5). Be aware that it is cationic and may be incompatible with anionic ingredients like Hyaluronic Acid, Xanthan Gum, and Carbomer. If used as the primary preservative, ensure high manufacturing hygiene or combine it with other preservatives.
• Mild Preserved™ COS: A broad-spectrum preservative effective against bacteria, mold, and yeast. It is water-soluble, odorless, and works in a wide pH range (2-8). Add it below 45°C.
• Preserve-BSB™ (eq. Optiphen BSB-W): A blend of Sodium Benzoate, Potassium Sorbate, and Benzyl Alcohol. Effective against bacteria, mold, and yeast, suitable for natural products. Works in pH 2-5.5. Water-soluble, can be added below 80°C.
• NaturePreserve™ LB2: A natural origin, water-soluble, broad-spectrum preservative. Highly effective against bacteria and fungi at low pH (2.0-6.5). Avoid heat above 50°C.

The choice of preservative depends on your specific mascara formula, including its pH, other ingredients (especially thickeners or charged ingredients), and manufacturing process. The most crucial step is to perform a Challenge Test on your final mascara formula to confirm that the chosen preservative system is effective in preventing microbial contamination throughout the product's intended shelf life.