Cosmetics Preservative Efficacy Challenge Testing

Challenge test for cosmetics preservative systems that help you to ensure microbial quality, demonstrating preservative efficacy during product shelf-life

Cosmetic preservative challenge tests ensure that the risk of microbial growth is minimised during normal conditions of storage or use over the expected shelf-life of the product. Preservatives are included in most cosmetic product formulations to protect them from microbiological contamination during normal consumer use to maintain quality and safety of the product. The purpose of the challenge test or preservative efficacy testing is to demonstrate the efficacy of the preservative system during the shelf and usage life of the cosmetic product. This is a regulatory requirement aimed at reducing risks to consumer safety.

Challenge Test Solutions
During these studies, we challenge the cosmetic to resist microbial development (for example, typically for 28 days at 32.5°C), which makes it possible to best represent its shelf life and time-in-use. Microorganisms are introduced to the formulation under controlled conditions and then at regular and defined intervals, analysis is carried out according to a validated protocol to determine the efficacy of the preservative system. For the product to pass the testing, its preservation system has to be sufficiently effective to reduce the level of microorganisms to allowed, predefined microbial limits. We can conduct challenge tests according to a range of standards such as United States Pharmacopeia (USP), ISO 11930, European Pharmacopoeia (EP) and Cosmetic, Toiletry and Fragrance Association (CTFA) Microbiology Guidelines.

Challenge Test According to ISO 11930
Our European centre of excellence for cosmetics testing, LaCoMed, is located near Chalon-sur-Saône in France and this team conducts preservative efficacy testing according to the ISO 11930 standard - Evaluation of the antimicrobial protection of a cosmetic product) either by the reference method (manual method) or by an automated method (using TEMPO CT instrumentation) which has been internally validated on a wide range of cosmetics ranging from simple matrices to more complex matrices. Microorganisms used for challenge testing are usually the following: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans and Aspergillus brasiliensis. Other microorganisms can be added if required. 

Total Quality Assurance
Bringing quality and safety to life, we offer a toolbox of Total Quality Assurance Solutions for cosmetics, supporting you across product innovation, raw materials qualification, stability studies, microbial quality, clinical studies and regulatory guidance. We offer a wide breadth of sector-dedicated technical solutions underpinned by 20 years of proven expertise in cosmetics testing delivered from our centres of excellence for cosmetics testing.


Need help or have a question? +1 217 352 6060

Need help or have a question?

+1 217 352 6060
+33 (0) 385 99 12 80
+44 116 296 1620
+852 2173 8888