Preservative Efficacy Testing

Preservative efficacy testing determines the effectiveness of a preservative during its shelf life and evaluates how well a product withstands microbial contamination during use. For example, in the case of sterile vials containing multiple doses, antimicrobial preservatives are used to inhibit the growth of any microorganisms that may be introduced during repeated insertion and withdrawal to load individual doses.

Preservative efficacy testing can also be used to determine the best preservative to use in your formulation and the minimum effective concentration of that particular preservative needed to preserve the pharmaceutical, food, or biotechnology product being assessed. Note that the minimum effective concentration of a preservative should be well below any concentration level that is toxic to humans.


CTFA Technical Guidelines: Microbiology Guidelines: M-3: Determination of Preservation Adequacy of Water-Misceible Cosmetic and Toiletry Formulations

CTFA Technical Guidelines: Microbiology Guidelines: M-5: Methods for Preservation Testing of Nonwoven Substrate Personal Care Products

USP <51> Antimicrobial Effectiveness Testing

Final Reports

Upon completion of test, a final report will be issued and all records and raw data will be held for five years.

Experience you can trust

Millstone Testing Services offers comprehensive regulatory testing services backed by more than 90 years of combined experience in the medical device and pharmaceutical sectors.