Feasibility study for the development of certified reference materials for specific migration testing. Part 1:...

The paper describes a project with the main objective of developing the know how to produce certified reference materials (CRMs) for specific migration testing. Certification parameters discussed are the initial concentration of the migrant in the polymer (C(P),0) and the specific migration into a food simulant under certain temperature/time conditions. Sixteen preliminary candidate CRMs were defined and produced. The most important polymers (low- and high-density polyethylene (LDPE and HDPE), polypropylene (PP), polystyrene (PS), polyethylene terephtalate (PET), plasticized polyvinyl chloride (PVC), rigid PVC, polyamides (PA)) and additives as well as monomers representing different physicochemical properties as target substances for migration were chosen. The stability and homogeneity of the migrants in the materials were tested and methods for the determination of the certification parameters were developed and validated. > From the 16 materials produced, the six most suitable CRM candidates (LDPE//Irganox 1076/Irgafos 168, LDPE//1,4-diphenyl-1,3-butadiene (DPBD), HDPE//Chimassorb 81/Uvitex OB, PP homo//Irganox 1076/Irgafos 168, HIPS, 1% mineral oil//styrene, PA 6//caprolactam) were selected. The feasibility of CRM production for the six candidate materials was demonstrated and a trial certification exercise was performed with participation of all four partner laboratories. All six materials showed suitable properties for future production as certified reference materials.