In an article published on October 30, 2021, in the peer-reviewed journal Food Packaging and Shelf Life, Zhi-Feng Chen from the Jinan University, Zhuhai, China, and co-authors reported on a method to differentiate recycled from virgin polyethylene (PE) based on the migration of untargeted substances. The scientists performed migration experiments according to the EU regulation for plastic food contact materials (FCMs) with eight virgin and 14 recycled PE materials, and they analyzed the migrating chemicals by combining untargeted gas chromatography coupled to a mass spectrometer (GC-MS) with multivariate data analysis.
In total, they detected 80 (semi-) volatile compounds of which 70 were tentatively identified including ester, hydrocarbons, alcohols, acids, benzene derivates, ketones, amides, aldehydes, ethers, and piperazine derivatives. Chen et al. also identified differences between virgin and recycled materials such as a higher number of species and average content of hydrocarbons in virgin PE, while additives and contaminants had a greater abundance in the recycled materials. The researchers reported that their principal component analysis model “showed the possibility of evaluating comprehensively the cleaning efficiency of the recovery process.” In addition, 38 markers were selected to develop a classification model to discern between virgin and recycled PE. Apart from one, all markers were found to have a higher presence in the recycled samples. The authors conclude that “the identification of recycled PE and virgin PE based on the migration of untargeted substances is feasible” and that “with the accumulation of samples, the classification model will be more and more stable and accurate.”
The EU Circular Economy Action Plan sets mandatory requirements for recycled content (FPF reported). Concerns have been raised about whether recycling targets can be met (FPF reported), which is making discussion on how recycling can be improved essential (FPF reported).
In an article published on November 8, 2021, in the journal Sustainable Production and Consumption, Spyridioula Gerassimidou and co-authors from Brunel University London, UK, evaluated the role stakeholders play in increasing plastics recycling rates and circularity in the UK. The researchers used the value chain of polyethylene terephthalate (PET) drink bottles as a case study and analyzed the complex stakeholder interactions by integrating stakeholder theory into the Complex Value Optimization for Resource Recovery (CVORR) system-based approach. CVORR was first described by Iacovidou et al. 2017 and has previously been applied by Gerassimidou and colleagues to compare the sustainability impacts of fossil carbon-based and bio-based plastics (FPF reported).
In their current study, the authors found that producers and brand owners, i.e., the stakeholders upstream of the PET value chain, have great lobbying power since the PET bottle market is well-established in the UK and financially supported. According to the article, this, in turn, incentivizes production and results in the burden on stakeholders located downstream in the PET value chain, such as the waste management industry. In addition, other stakeholders external to the value chain, such as NGOs and trade associations, were found to “lack the power and incentives to shift attention upstream.” In the current situation, “the waste management processes are short-sighted, being unable to gain improved momentum and increasing the PET bottles recycling rates.” Gerassimidou and co-authors conclude that all stakeholders involved in the system need to collaborate to develop “new value networks and support new policy interventions that can improve circularity in the plastic packaging sector.”
Some of the co-authors previously published a report investigating England’s management of plastic packaging waste and identified needed improvements such as a better distribution of value across the system using extended producer responsibility and deposit schemes (FPF reported).
Chen, Z. (2021). “Identification of recycled polyethylene and virgin polyethylene based on untargeted migrants.” Food Packaging and Shelf Life. DOI: 10.1016/j.fpsl.2021.100762
Gerassimidou S. (2021). “Unpacking the complexity of the UK plastic packaging value chain: A stakeholder perspective.” Sustainable Production and Consumption. DOI: 10.1016/j.spc.2021.11.005