However, one of the most common misunderstandings in the cosmetic industry is that the European Union has a fixed list of mandatory laboratory tests that every cosmetic product must pass.
In reality, cosmetic testing requirements are largely risk-based. A face cream, solid soap, body oil, sunscreen, and eye product do not necessarily require the same testing programme. The formulation, product type, packaging, target user, intended area of application, and product claims all influence which studies may be necessary.
The Cosmetic Product Safety Report Determines the Evidence Needed
The CPSR is central to cosmetic compliance in the European Union.
Part A of the CPSR contains the cosmetic product safety information. This includes information about the qualitative and quantitative composition, physicochemical characteristics and stability, microbiological quality, impurities and traces, packaging material, normal and reasonably foreseeable use, exposure, toxicological profiles, and undesirable effects.
Part B contains the actual safety assessment and the safety assessor’s conclusion.
The safety assessor evaluates the available information and determines whether the evidence is sufficient to conclude that the product is safe. If important information is missing, additional data or testing may be necessary.
For this reason, manufacturers should consider testing requirements during product development rather than waiting until the final CPSR is being prepared.
Stability Testing
Stability testing is one of the most important evaluations for cosmetic products.
The objective is to determine whether the formulation remains physically and chemically stable throughout its intended shelf life. Laboratories may monitor characteristics such as appearance, color, odor, pH, viscosity, phase separation, and other product-specific parameters.
The type and extent of stability evaluation should be appropriate for the formulation.
Microbiological Testing
The microbiological quality of a cosmetic product must also be considered as part of the safety assessment.
Products containing water generally present a greater potential for microbial growth than anhydrous formulations. However, the actual microbiological risk depends on the complete formulation, manufacturing conditions, packaging, and intended use.
Microbiological testing can be used to determine whether the finished product complies with appropriate microbiological quality criteria.
Products intended for use around the eyes, on mucous membranes, on damaged skin, or by children under three years of age require particular attention during the microbiological assessment.
The need for testing should be evaluated according to the product’s risk profile.
Preservative Efficacy Testing
A preservative efficacy test, commonly called a challenge test, evaluates whether a cosmetic product can control microbial contamination introduced during use.
During the study, the product is deliberately exposed to specified microorganisms. The laboratory then monitors how effectively the formulation reduces or controls these microorganisms over a defined period.
Challenge testing is particularly relevant for water-containing products and formulations that may support microbial growth.
However, not every cosmetic product presents the same microbiological risk. Certain low-risk products may not require the same level of preservative efficacy evaluation if the absence of such testing can be scientifically justified.
Packaging Compatibility Testing
The packaging used for a cosmetic product should be suitable for the finished formulation.
Packaging compatibility studies evaluate whether interactions develop between the cosmetic product and its container over time. Potential problems may include leakage, evaporation, corrosion, swelling, cracking, discoloration, or changes to the cosmetic formulation.
Information concerning the packaging material is also considered in Part A of the CPSR.
Compatibility testing is especially important when formulations contain ingredients such as essential oils, fragrances, solvents, alcohol, or other substances that may interact with certain packaging materials.
The final commercial packaging should therefore be considered during product stability and safety evaluation.
SPF and UVA Testing
Products making sun protection claims require specific efficacy evidence.
An SPF value cannot simply be calculated from the percentage of UV filters used in the formulation. The finished product must provide evidence supporting the claimed level of protection.
SPF testing evaluates protection primarily against UVB radiation, while separate UVA evaluation is used to assess protection across the UVA range.
European Commission Recommendation 2006/647/EC provides guidance on sunscreen efficacy and related claims. It recommends that UVA protection should be at least one-third of the labeled SPF and that the critical wavelength should be at least 370 nm.
Manufacturers making SPF, UVA, or broad-spectrum protection claims should use appropriate recognized testing methods to substantiate these claims.
Testing to Support Cosmetic Claims
Not all laboratory testing is directly related to product safety.
Some studies are performed to substantiate marketing claims.
Commission Regulation (EU) No. 655/2013 establishes common criteria for the justification of claims used in relation to cosmetic products. Claims should be supported by adequate and verifiable evidence.
For example, claims such as “24-hour hydration,” “reduces the appearance of wrinkles,” “improves skin elasticity,” or “long-lasting makeup” may require instrumental, clinical, consumer, or other appropriate efficacy studies.
The type of test depends on the wording of the claim and the effect being communicated to consumers.
A stronger or more specific claim will generally require stronger supporting evidence.
Dermatological and Tolerance Testing
Terms such as “dermatologically tested” are commonly used on cosmetic products, but they have to be supported by appropriate evidence.
Human compatibility or tolerance studies may be performed to evaluate how a finished cosmetic product is tolerated under defined conditions of use.
Additional studies may be considered for products intended for sensitive skin, the eye area, lips, intimate areas, or other sensitive application sites.
However, there is no single universal “dermatological test” legally required for every cosmetic product sold in the EU.
The need for tolerance studies depends on the formulation, intended use, target population, existing safety data, and the claims made for the product.
Eye Area Products
Cosmetics intended for use around the eyes require particular attention.
The safety assessor should consider the possibility of accidental contact with the eye as part of normal or reasonably foreseeable use.
Depending on the product and its formulation, additional ophthalmological or ocular tolerance evaluation may be appropriate.
Products such as mascara, eyeliner, eye creams, makeup removers, and certain facial products may require a different assessment approach from products intended exclusively for use on less sensitive areas of the body.
The need for specific testing should be determined according to the expected exposure and potential risks.
Products for Children and Other Sensitive Groups
The target user is an important factor when defining a cosmetic testing programme.
Regulation (EC) No. 1223/2009 requires the safety assessment to consider the intended use and exposure to the product. Particular attention is required for cosmetic products intended for children under three years of age and products intended exclusively for external intimate hygiene.
Products intended for sensitive populations may therefore require additional safety considerations or supporting data.
This does not mean that a single predefined test is automatically required for every product marketed to a sensitive group. Instead, the safety assessment should reflect the characteristics and vulnerability of the intended users.
Can Existing Ingredient Data Replace Finished Product Testing?
Existing scientific data on cosmetic ingredients is essential for the safety assessment.
Safety assessors use toxicological information, regulatory restrictions, exposure data, impurity profiles, and other available scientific evidence when evaluating a formulation.
However, ingredient data cannot always predict how the finished cosmetic product will behave.
Interactions between ingredients can influence stability, preservation, viscosity, pH, and product performance. Manufacturing processes and packaging may also affect the final product.
For certain aspects of the assessment, finished product data is therefore important.
The balance between existing scientific information and additional laboratory testing should be determined on a case-by-case basis.
A Risk-Based Approach to Cosmetic Testing
There is no single laboratory testing package suitable for every cosmetic product sold in the European Union.
A typical water-based cosmetic may require stability evaluation, microbiological quality testing, and preservative efficacy testing. A sunscreen requires specific efficacy studies to support SPF and UVA claims. A product making measurable performance claims may require claim substantiation studies. An anhydrous product may require a different stability and microbiological assessment strategy.
The appropriate tests depend on the product.
For manufacturers, the most effective approach is to evaluate the formulation, packaging, intended use, target users, exposure, and claims as a complete system. Testing can then be selected to address the specific risks and evidence requirements identified during product development.
