Recently, the University of Pisa, in collaboration with Biorepack, the Italian National Union for Organic Recycling of Compostable Bioplastics, developed an innovative method to detect and quantify non-biodegradable substances maliciously added during the production of biodegradable and compostable plastic packaging. The findings have been published in the journal *Analytical and Applied Pyrolysis*.
1. Malicious Addition of PE to Biodegradable Plastics
This research addresses a significant environmental issue that has not yet received widespread attention. To ensure bioplastics meet compostability and biodegradability standards, EU regulations explicitly limit the addition of non-biodegradable polymer polyethylene to 1%.
The EU's new *Scheme for Certification of Industrial Compostable Materials*, which came into effect on January 1, 2026, reduces the total percentage limit for organic compounds (without biodegradability testing) to 3% from 5% to 1%. Previously, some paper-plastic tableware with acrylic coatings (acrylic coating weight ≥3%) and some PBAT biodegradable bags with added PE to enhance toughness will no longer be certified.
Current test results show that about half of the plastic bags sampled exceeded the standards, with polyethylene content reaching as high as 5%, and most of these substandard products originated outside the EU.
Furthermore, a survey by the industry association Assobioplastiche revealed that one in four plastic bags on the Italian market is non-compliant, with annual violations exceeding 20,000 tons. Stricter measures are planned, with violations facing a uniform penalty of €2,500 to €25,000.
However, there has been a lack of effective testing methods to verify whether companies are complying with these limits. The new testing tool developed by the University of Pisa successfully fills this technological gap.
Innovative Methods Detect PE Content Below 1%
Professor Marco Mattonai of the University of Pisa emphasized, "Simply labeling products as biodegradable and compostable is far from enough. The key is to verify whether they actually meet standards to prevent plastic residues from remaining in the natural environment for extended periods."
Stricter testing and control of compostable materials not only helps reduce microplastic release from soil and water and improve the quality of agricultural compost, but also curbs the misuse of "biodegradable" and "compostable" labels by companies, effectively protecting the rights of those operating legally and in compliance with Italian and EU regulations.
Professor Erika Ribechini of the same university added, "With the analytical method we developed, we can now conduct efficient and reliable testing on samples with complex compositions, with short testing times and controllable costs. This tool provides practical technical support for environmental protection and ensuring consumers' right to know and right to supervise."
In practical application, this testing solution, based on analytical pyrolysis coupled with mass spectrometry, can detect polyethylene content below 1%, with detection accuracy fully meeting regulatory limits. This also makes the tool an effective means of industrial quality control and environmental regulation. Carmine Pagnozzi, Chief Engineer of the Biorepack Alliance, summarized: "Ensuring the industry strictly adheres to stringent regulations in the field of compostable bioplastics is one of our alliance's statutory goals.
Only in this way can we ensure that compostable bioplastics, when composted together with other organic waste, truly benefit the soil and the agricultural supply chain. Therefore, we are very honored to support the development of such accurate and reliable scientific testing tools, helping Italy further consolidate its leading position in the European sustainable bioplastics supply chain."
