Use of simulation (introduction)

Polymeric materials are used in a variety of applications. Through all the following applications direct or indirect consumer exposure with substances (chemicals) from polymeric materials may occur.
- food contact materials and articles
- toys
- textiles
- child use and care articles
- medical devices
- drinking water applications
- household articles
- consumer goods
- construction materials
- automotive applications
- electronics applications
- other materials and articles

Due to interaction between polymeric materials and contacting media, and consumer exposure resulting there from, legal requirements are set at national and international level. For given applications like food contact materials or toys detailed legal requirements in terms of substance specific migration limits are set by the applicable legislation. Historically the experimental approach, i.e. experimental migration testing under conventional test conditions was used for compliance assessment.

Migration modelling is a valuable tool to estimate the type and extend of interaction between polymeric materials and contacting media. Estimating the mass transfer based on the relevant physical and chemical parameters, i.e. mass transfer constants, enable professionals to estimate consumer exposure at all stages of the production chain.

In the last years migration modelling got more and more accepted and was first introduced in legislation for plastic food contact materials and articles allowing for compliance assessment with applicable legislation.

Food contact materials

EU legislation
Migration modelling was introduced in the EU legislation for materials and articles intended to contact food with the 6. Amendment of Directive 90/128/EEC, today consolidated in Directive 2002/72/EC. The consolidated Plastics Directive 2002/72/EC was amended itself four times until now.
Migration modelling was implemented in the EU legislation with the following wording:

Detailed information about the general recognised diffusion models based on scientific evidence can be found in the Practical Guide in support of the Plastics Directive as well as on this web site.
According to Article 8 of Directive 2002/72/EC migration modelling can be used to demonstrate compliance of food contact materials and articles with the applicable legislation. To demonstrate non-compliance, i.e. by official control, the experimental approach is obligatory.

other applications

Strong efforts are made to get migration modelling accepted for all applications were polymeric materials are used like:
- toys
- textiles
- child use and care articles
- medical devices
- drinking water applications
- household articles
- consumer goods
- construction materials
- automotive applications
- electronics applications
- other materials and articles
Because interaction between plastic materials and contacting media, i.e. migration and emission processes follow the same laws independent from the application one can expect that this objective will be achieved in near future.