What testing is necessary for my cosmetic product?

There are 3 types of testing required:

1. Stability test
2. Compatibility test
3. Microbial Challenge test
   
   

Stability testing 

The purpose of a stability test is to evaluate the stability and consistency of a product's formula. This test is mandatory for all cosmetic products according to EC 1223/2009. Therefore, the stability test is a crucial component of the Cosmetic Product Safety Report (CPSR), ensuring the safety and longevity of the formula. The stability test can include a compatibility test, where the product is tested in its final packaging. 

Why a stability test is performed

Time might influence the characteristics and safety of a product. For example, over time, the colour, smell and pH of a product might change. In order to assess the safety of a product over time, a stability test is performed. The stability test is also needed to inform consumers about the expiry of the product. EC 1223/2009 states that for the use of a period after opening (PAO) symbol, you must be able to demonstrate that your product stays stable for at least 30 months. Otherwise, a best before period or hourglass symbol must be used.

How a stability test is performed

Since it is not very practical to wait 30 months in order to see whether time influences the product in a negative way, this process is imitated by storing the product in a hot oven. This accelerates the process greatly.
This way, the stability test takes approximately 16 weeks to perform. If all characteristics of the product remain the same after performing the stability test, the safety of the formula of the product can be guaranteed over time. The results of the stability test will be included in your CPSR.

Compatibility testing

A compatibility test is performed to assess the stability of the product when it is in its final packaging. This test ensures that the product's formulation does not interact negatively with the packaging and vice versa. It helps to identify any potential issues such as unwanted substances migrating from the packaging to the formulation, loss of odor due to migrating fragrance, or packaging deterioration caused by the formulation. The compatibility test includes measuring organoleptic qualities, viscosity, and pH of the product. It is typically conducted at room temperature, and accelerated temperatures, and can also include refrigerated conditions if requested. Similar to the stability test the full test duration is 16 weeks.

If a stability test is performed on a product in its final packaging, its compatibility can be tested at the same time. 

Microbial Challenge test

A microbiological challenge test is conducted to ensure that your product and its preservatives perform their intended functions effectively.. The purpose of a microbiological challenge test is to determine whether any growth of bacteria, fungi, or mold on the product is effectively inhibited. This test ensures that the product and its preservatives are able to prevent the growth of harmful microorganisms. By injecting bacteria, fungi, or mold into the product, the challenge test simulates typical usage conditions where these microorganisms may come into contact with the product. If the product allows for unrestricted growth of these microorganisms, it could pose a risk to the consumer.

How a Microbial Challenge test is performed 
There are various protocols available for conducting a challenge test. These protocols can be developed by international communities such as ISO standards and Pharmacopeiae. They can also be developed by companies, which often are suppliers of preservatives.
The protocols used for challenge testing can vary, and not all protocols are accepted for cosmetics on the EU market. It is important to ensure that you are using an accepted method for your challenge test by consulting with a microbial lab or safety assessor. For instance, the EP (European Pharmacopoeia) is a method that is widely recognized and accepted within the EU, but it may not be applicable to methods developed outside of the EU.

It is important to consult with a microbial lab or a safety assessor to ensure that you are using a reliable and effective method for conducting the challenge test. Their expertise will help you determine the most suitable approach for your specific product. Common microorganisms used for challenge testing include various bacteria such as Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, as well as two fungi called Candida albicans and Aspergillus brasiliensis. These microorganisms are used to simulate typical usage conditions and determine if a product's preservatives effectively inhibit their growth, ensuring the safety and effectiveness of the product for consumers.

There are cases in which Microbial Challenge testing is not necessary. Please check following page to see if your product needs Microbial Challenge tests: Does my product need Microbial Challenge testing?

Where can I send my product to get it tested?

On this page  we suggest multiple companies that can test your products for you.

We hope to have informed of challenge- stability and compatibilitytesting, what they are and when you are obligated to perform the tests in accordance with EU legislation. If you have other questions about testing, please contact: office@skinconsult.com.


Remember, safety first!