Answer:
The use of post-consumer polyolefins is increasing due to the pledges of multiple organizations to use higher concentrations of recycled materials in packaging. However, direct food contact applications are challenging with various regulations around the world mandating minimum safety requirements, which is often determined by the condition of use (microwave, cold storage) and food type (fatty, aqueous, dry). This article reviews different predictive models that have been developed to study contaminant migration from packaging to food contact articles. It also examines multiple techniques and methods that have been employed to quantify and assess to the safety of recycled materials (e.g., United States and Europe) which serve as a base for the regulatory framework for many other countries. The presence of different contaminants during polymer processing is also discussed due to potential problems from the presence of harmful compounds affecting human health or degradation of material properties.