Evaluation of the chemical inertness of a material (food contact)

Assessing the chemical inertness of a food contact material is a crucial step in ensuring consumer safety and regulatory compliance for products placed on the market. A material is considered chemically inert when it does not transfer substances that could alter the composition, organoleptic properties, or food safety of the food. This analysis is essential for manufacturers of packaging, materials, and polymers, who face stringent regulatory requirements at the European level. It demonstrates that the material does not react chemically with food, even under harsh conditions such as heat, prolonged storage, or contact with acidic or fatty matrices.

European regulatory framework and requirements

Materials intended for food contact are governed by a set of European regulations, notably Regulation (EC) No 1935/2004, which requires that these materials pose no risk to human health. For plastics, Regulation (EU) No 10/2011 defines specific migration limits for certain substances and precise test conditions. Other regulations apply to metals, ceramics, paper, cardboard, and glass. The assessment of chemical inertness is therefore part of a comprehensive regulatory approach aimed at demonstrating material conformity, ensuring the safety of the production chain, and meeting the requirements of the competent authorities.

Principle and procedure of the evaluation

The assessment of chemical inertness relies on conducting overall and specific migration tests, as well as analyzing substances potentially released by the material. These tests are performed by exposing the material to representative food simulants (aqueous, acidic, alcoholic, or fatty) under time and temperature conditions defined by regulations.
Overall migration measures the total quantity of substances transferred from the material to the simulant, providing an initial indication of the material's overall behavior.
Specific migration targets identified or suspected substances, such as monomers, additives, plasticizers, metals, or residual contaminants.
The analyses may also include absorption or release tests, allowing for the evaluation of interactions between the material and the food, as well as the evolution of these interactions over time.

Analytical techniques implemented

The assessment of chemical inertness relies on high-precision analytical techniques. HPLC and LC-MS are used to detect and quantify organic compounds, such as additives, manufacturing residues, or migrating contaminants. These methods offer high sensitivity and allow the identification of substances at very low concentrations.
ICP-MS and ICP-AES/ICP-OES techniques are preferred for the analysis of metallic elements that may be released by metallic materials, ceramics, or certain pigments. They allow the measurement of trace metals with excellent precision, essential for verifying compliance with regulatory limits.
The choice of techniques depends on the type of material, the nature of the substances being analyzed, and the applicable regulatory requirements.

Industrial applications

This assessment covers a wide variety of materials that come into direct contact with food. In plastic packaging, it validates the compatibility of films, trays, bottles, and caps with different types of food. For metallic and ceramic materials, it is essential to prevent the release of heavy metals or other undesirable elements. Paper, cardboard, and fiber-based materials are also included, particularly for evaluating the transfer of substances from inks, adhesives, or surface treatments.
Manufacturers use these analyses both during product development and quality control, to qualify suppliers, validate formulation changes, and ensure safe market entry.

Analyzed matrices

Chemical inertness testing is applicable to plastics, polymers, metals, alloys, ceramics, glass, paper, and cardboard, whether intended for direct or indirect food contact. Tests can be performed on finished products, semi-finished products, or raw materials, taking into account the actual conditions of use (temperature, contact time, type of food).

Added value YesWeLab

YesWeLab relies on a network of laboratories specializing in migration testing and the analysis of food contact materials. The majority of our partners are ISO 17025 and COFRAC certified or accredited, guaranteeing the reliability and compliance of the results. Our scientific team supports you in defining the test plan, selecting food simulants, interpreting the results, and compiling technical files that meet regulatory requirements. Since 2020, manufacturers, packaging companies, and engineering firms have entrusted us with the centralized management of their analyses via our digital platform, ensuring rigorous and responsive monitoring.

Related analyses in the YesWeLab catalog

To complete the assessment of chemical inertness, the following analyses are frequently associated:

• Global and specific migration tests
• Heavy metal analysis by ICP-MS
• Identification of migrating organic compounds by LC-MS
• FTIR analysis for material characterization
• Accelerated aging tests