Food packaging: The challenge test and the use of recycled plastic

The use of recycled material in food packaging is an opportunity for the sector but is subject to important environmental and health requirements that must be taken into account. We must not forget that recycled materials come from waste, either industrial or domestic, therefore, food safety is a critical point. It must be ensured that the final product is safe and does not pose a health risk.

In Spain, since 2008 and thanks to COMMISSION REGULATION (EC) No 282/2008, it is allowed to use recycled materials intended to come into contact with foods under the requirements set down therein.

Requirements for recycled material

The origin and journey of the product until it becomes waste and, afterwards, is recycled, is very important. There are different possibilities of use for recycled material and each one involves specific requirements:

Industrial offcuts. Use of recycled material coming from industrial, pre-consumer food waste. In this case, materials follow basic legislation and do not require specifications different from those of virgin material, including good manufacturing practices and the impossibility of contamination within the plant itself (inks, adhesives).
Recycling after functional barrier. In this case, recycled materials are not in direct contact, in other words, in the internal layer of a multilayer packaging. This functional barrier prevents substances that are behind it from migrating to the foodstuffs.
Authorisation of the plant and/or processes that produce the recycled material or the recycled product by the European Food Safety Authority (EFSA). Besides meeting the same requirements as virgin material, the material must meet additional requirements due to its potential risk.

Among other aspects, to authorize plants, waste must:

Be analysed and controlled.

Have food origin: waste generated from materials and articles intended to come into contact with foods or with a formulation as such.
Come from a closed and controlled chain circuit that ensures the non-contamination.
Processes demonstrating decontamination.

But, how can we ensure materials have been decontaminated so that they do not pose a risk to human health? And how can we ensure that the functional barrier is effective?

To achieve this, a test protocol must be established in which a material contamination procedure is established for the worst case that enters the recycling and/or transformation process and a subsequent evaluation of the result. It is called the ‘Challenge Test’ and analyses the efficiency of the cleaning procedures to decontaminate plastic materials or articles, as well as the effectiveness of the functional barrier.

The Challenge Test step by step

1. The material (sheet, shredded product, pellet, etc.) is contaminated with model contaminants. The choice of these depends on the worst-case scenario, the kind of waste and its possible route, adapting them to each case both in terms of origin and concentration.
2. The contaminated material is analysed to see the contamination degree obtained (it can be the maximum or the previously established).
3. a) The contaminated material is subject to a recycling and/or transformation process. In most cases, super cleaning technology is required. There are different super-cleaning processes, such as the decontamination treatment used, the material, the contamination degree, etc.

b) The contaminated material is introduced into the middle layer of a multilayer structure. The outer layers act as a functional barrier.

1. a) The obtained material is analysed after the process to see whether the contaminants added initially are still present and their concentration. This will allow seeing the effectiveness of the decontamination and comparing the results with the threshold established by the EU legislation.

b) Migration tests are performed with suitable simulants to determine that the contaminated material does not migrate out through the functional barrier layers.

Recycled materials in Spain

Europe has already issued scientific opinions on the authorizations submitted initially, pending publication of the authorization numbers. In Spain, recycled material can be used with the authorization of their countries or a favorable scientific opinion.

If the recycled material comes from Spain, given that there was no national authorization until the definitive publication of the authorization number, it can be used for food contact as long as:

EFSA has emitted a favorable opinion on the plant.
The company responsible for the recycling process has informed the competent health authorities of the region where the facilities are located of the beginning of the manufacture of this material to make its official control easier.
The company responsible for the recycling process ensures that the recycled material has been obtained following the manufacturing conditions laid down in the EFSA opinion.
Operators ensure that the terms and conditions laid down in COMMISSION REGULATION (EC) No 2023/2006 and assessed by the EFSA are met.
In the case of using a functional barrier, the company has carried out the necessary migration tests with positive results.