Laboratory Testing
Laboratory Testing
Laboratory testing is essential to assess the safety, quality and stability of a cosmetic product before and after it is placed on the market.
Every cosmetic product must be supported by appropriate technical documentation, consistent with its composition, intended use, area of application and product characteristics.
Through a network of qualified laboratories, partner companies and specialised facilities, support can be provided in selecting and carrying out the most suitable tests for finished cosmetic products, raw materials and formulations under development.
Laboratory tests may be useful to:
- support the preparation of the Product Information File;
- integrate the cosmetic safety assessment;
- verify the microbiological quality of the product;
- assess the stability of the formulation;
- check compatibility between product and packaging;
- respond to requests from clients, distributors or competent authorities;
- prepare documentation for foreign markets.
How to Choose the Most Suitable Tests
Not all cosmetic products require the same tests.
The choice of the tests to be performed should be assessed on a case-by-case basis, considering several factors:
- type of product;
- formulation;
- presence or absence of water;
- area of application;
- frequency and method of use;
- target consumers;
- presence of functional ingredients;
- type of packaging;
- target market.
A well-planned testing strategy helps avoid unnecessary analyses while building solid and coherent technical documentation for the product.
Safety and Skin Tolerance Tests
Safety and skin tolerance tests are used to assess the compatibility of a cosmetic product with the skin and to identify any possible irritation or undesirable skin reactions.
These tests are particularly useful for leave-on products, products intended for sensitive skin, facial cosmetics, baby products, cleansers, make-up and innovative formulations.
Patch Test
The Patch Test is used to evaluate the primary skin tolerance of a cosmetic product.
The product is applied to the skin under controlled conditions in order to verify the possible appearance of visible reactions, such as redness, swelling or irritation.
Different types of Patch Tests may be considered, including:
- 48-hour Patch Test;
- Patch Test on normal skin;
- Patch Test on sensitive skin;
- occlusive Patch Test;
- semi-open Patch Test;
- open Patch Test.
The Patch Test may be used to support the safety assessment and skin tolerance evaluation of the product.
Challenge Test
The Challenge Test, also known as the preservative efficacy test, assesses the ability of a cosmetic product to resist microbial contamination during use.
The test is performed through the controlled inoculation of microorganisms into the product, followed by monitoring over time to verify the effectiveness of the preservative system.
It is particularly recommended for:
- emulsions;
- creams;
- gels;
- cleansers;
- water-containing products;
- multi-use products;
- cosmetics intended for prolonged use after opening;
- formulations more exposed to the risk of contamination.
The Challenge Test is one of the most important tools to demonstrate that the chosen preservative system is suitable for the formulation.
Microbiological Analyses
Microbiological analyses are used to verify the hygienic quality of the cosmetic product and the absence of undesirable microorganisms.
The main microbiological analyses include:
- total aerobic microbial count;
- yeasts and moulds;
- Escherichia coli;
- Pseudomonas aeruginosa;
- Candida albicans;
- Staphylococcus aureus.
These controls are essential to assess the microbiological suitability of the product and its compliance with applicable safety requirements.
Stability Testing
Stability tests are used to evaluate the behaviour of the cosmetic product over time and under different environmental conditions.
During the study, several parameters may be monitored, including:
- appearance;
- colour;
- odour;
- pH;
- viscosity;
- consistency;
- phase separation;
- organoleptic changes;
- compatibility with packaging;
- possible product alterations.
Stability testing is useful to support the definition of product durability, PAO, storage conditions and the overall quality of the formulation.
Product-Packaging Compatibility
Compatibility between the formulation and its packaging is an important aspect that should not be underestimated.
Packaging may affect the stability, preservation and quality of the cosmetic product. For this reason, it may be useful to assess possible interactions between the container and the formulation, such as changes in colour, odour, consistency, product leakage, packaging deformation or incompatibility with specific materials.
Heavy Metals and Nickel Analysis
Heavy metal analysis allows the detection of possible unwanted impurities in the cosmetic product or in raw materials.
Tests may be performed for several metals, including:
- nickel;
- lead;
- cadmium;
- chromium;
- cobalt;
- arsenic;
- mercury.
The Nickel Test is often requested for products intended for sensitive consumers or to support specific declarations, always in accordance with analytical limits and available documentation.
Cytotoxicity Test
The cytotoxicity test is used to assess the potential toxic effect of a product, ingredient or extract on cell cultures.
It may be used as supporting evidence for specific formulations, products intended for sensitive areas or where particular technical documentation is required.
Testing for Sun Care Products
Sun care products require specific tests to support indications related to UV protection.
The main available tests may include:
- determination of the Sun Protection Factor, SPF;
- assessment of UVA protection;
- in vitro tests for UVA protection;
- in vivo tests for SPF determination, where applicable;
- tests supporting UVA/UVB protection declarations;
- assessments related to specific sun protection statements.
These tests are essential for products that include references to sun protection, UVA protection, UVB protection or other indications related to sun exposure.
Testing on Raw Materials and Formulations under Development
In addition to tests on finished products, analyses may also be carried out on raw materials, semi-finished products or formulations under development.
This activity may be useful to:
- compare different formulations;
- select functional ingredients;
- perform preliminary stability checks;
- assess compatibility between ingredients;
- support new product development;
- identify potential issues before final production.
Additional Tests upon Request
In addition to the most common analyses, further tests may be evaluated depending on the product characteristics, regulatory needs or target market.
Each product is assessed individually in order to identify the most suitable and proportionate testing plan.
Support in Defining the Testing Plan
The choice of laboratory tests should not be random.
A well-structured testing plan allows companies to obtain useful data, avoid unnecessary analyses and prepare documentation consistent with the Product Information File, the safety assessment and the technical characteristics of the product.
Support can be provided in defining the most appropriate analytical plan by assessing formulation, intended use, target consumers, packaging and documentation requirements.
Technical Support for Targeted Tests and Coherent Documentation
Laboratory testing is an essential tool to ensure the safety, quality and reliability of cosmetic products.
The correct selection of tests helps support regulatory compliance, improve technical documentation and prevent potential issues during product development or market placement.
The most suitable tests must be evaluated on a case-by-case basis, according to the specific characteristics of the product, formulation, packaging, intended use and company objectives.
In this way, the testing plan becomes a truly useful tool: not only to complete the documentation, but also to prevent critical issues and support the quality of the cosmetic product more effectively.