Migration and food contact materials

As a professional, you naturally know all about food safety. But as a consumer, you may still be in for a few surprises. For example, that time when you took out a half-melted plastic container from the appliance while preparing a microwave meal. Do you remember it? Question: Did you just eat the meal afterwards?

Knowing more about the topic of migration, we were shocked like you when reading the above intro. Migration is the most researched and legislated food safety issue when it comes to food contact materials. We are not just talking about food packaging materials, but also consumer items that can come into contact with food and drink, such as cups, plates, equipment and machinery. Many of these products are made of plastic, paper, cardboard, glass or ceramics, for example.

Migration and health risk

The fact is that substances can be released from food contact materials and then end up in food. Exactly, this is called migration. Migration allows consumers to ingest the food. However, a risk assessment examines whether undesirable health effects may occur due to these substances. Depending on the risk assessment, a substance may or may not be authorised for use in food contact materials, coupled with migration limits.

Some examples of risks:

• a stirring spatula that gives off a colour to boiling water. This may give off substances that can damage health
• a tagine that releases heavy metals such as lead and cadmium, which can cause long-term damage
• . Substances released from PVC packaging, such as the carcinogen vinyl chloride
• printing inks on (recycled) packaging that deposit on the food. Substances, including mineral oils, may then be released that could cause harm to health

Legal framework in European and national regulations

Regulation (EC) 1935/2004 lays down general requirements for food contact materials. In addition, specific guidelines apply to, for example, plastics, ceramics and regenerated cellulose. There are also directives for recycled materials and active and intelligent packaging (for example, in case of spoilage, the packaging discolours). For other materials, national legislation applies. In the absence of these, the manufacturer is responsible for chemical safety.

Positive lists of substances

Plastics and regenerated cellulose are subject to positive lists of permitted substances in Europe (via EFSA).

Migration limits and testing (general and specific)

The migration of contaminants from packaging and other materials into food is determined by migration tests performed by an accredited laboratory. The following apply:

The global (general/total/general) migration limits. The limit that applies here is 60 mg/kg. This determines the total quantity of substances migrating from the material into a test liquid, specific migration limits (SMLs), maximum quantities (QMs), purity criteria, group limits (SLT(T)’s and use restrictions. A specific migration test determines whether a substance remains below the set limits.

Migration tests are mostly done with simulants, namely ethanol 10% (v/v), acetic acid 3% (m/v), ethanol 20% (v/v), ethanol 50% (v/v) and vegetable oil. Furthermore, the temperature and duration of migration are determined according to real use conditions or the ‘worst case’ scenario. This is done according to standard test conditions for time and temperature, among others. Sometimes, ‘worst-case’ scenarios are calculated, or migration modelling is used. The simulants and operating conditions used must match the requirements for the foodstuff with which the food contact material comes into contact.

Declaration of compliance

As a food producer or packager, you are surely familiar with the CoC or DoC. It states:

whether the producer of the contact material has already carried out the compliance work;

whether the packaging meets all legal requirements necessary for the application;

whether the contact material is suitable for the contact conditions of the product;

whether limits for certain food additives or food flavourings are not exceeded due to migration from the packaging