Effect of recycled content and rPET quality on the properties of PET bottles, part II: Migration

Abstract

Polyethylene terephthalate (PET) bottles were produced from three types of recycled PET (rPET) with four levels of recycled content. The migration of substances from these bottles to water was studied. Several migrated substances were detected. The migrated amounts of acetaldehyde and ethylene glycol complied with the limits given in the food contact material (FCM) legislation. Migration of 2‐methyl‐1,3‐dioxolane was below the limit of 10 μg·L−1, which is conventionally applied for non‐intentionally added substances (NIAS) not classified as ‘carcinogenic’, ‘mutagenic’ or ‘toxic to reproduction’ (CMR). Limonene, acetone, butanone and furan were also detected as migrants, of which limonene is a natural fragrant, and the other three are probably residues from solvents used to clean and protect the mould at the small‐scale production facility. Finally, benzene and styrene were also found as migrants from rPET. These migrants appear to originate from heat‐induced reactions within the PET matrix, which involve contaminants. The formation of benzene in rPET is attributed to polyvinylchloride as contaminant. The migrated amounts of benzene from the PET bottles with recycled content to the water simulant are relatively small (0.03–0.44 μg·L−1) after 10 days at 40°C. Consequently, the margin of exposure is 3.105–8.106. Hence, the level of concern for the public health is low, and the migrated amount represents a low priority for risk management. The FCM legislation demands a risk assessment for migrating NIAS. Depending on the underlying data and exposure scenario, different threshold limits in the food can be derived which can still be considered as safe.

Factors Shaping the Recycling Systems for Plastic Packaging Waste—A Comparison between Austria, Germany and The Netherlands

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Review on the photonic techniques suitable for automatic monitoring of the composition of multi-materials wastes in view of their posterior recycling

“…In Germany, PET bottle to bottle recycling is a special case of packaging recycling as it depends on a refund-based collection of PET bottles and a subsequent so-called “super clean” recycling process. Part of the PET recycling chain is an automated NIR or laser-based sorting of shredded and washed PET flakes targeting a negative sorting of non-PET materials from the bulk input ( van Velzen et al, 2020 ; Welle, 2014 ).…”

Technical Limits in Circularity for Plastic Packages

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