In a groundbreaking report, researchers from ETH Zürich have unveiled LitChemPlast, a comprehensive open-access database cataloguing over 3,500 chemicals detected in plastics. This initiative, detailed in Environmental Science & Technology Letters, compiles data from 372 studies conducted between 1978 and 2021, highlighting both known and less-explored substances across various plastic types and product categories.
Key Findings on Chemicals in Plastics
The LitChemPlast database marks a significant step in the understanding of plastic composition. Notably, the report identifies that approximately 75% of the detected chemicals were found through nontargeted screenings, showcasing the complex and often unexpected chemical landscape within plastics. These substances include hazardous compounds like brominated flame retardants, ortho-phthalates, and metal(loid)s, known for their toxic potential and persistence in the environment.
Moreover, the report reveals significant disparities in the coverage of different types of plastic products. While food packaging and electronic equipment (EEE) have been well-studied, economically critical areas like industrial packaging and automotive plastics have received less attention. The lack of comprehensive data poses risks for consumer safety and regulatory oversight.
The Recycling Challenge: Contaminant Risks
A central focus of the report is the comparison of virgin and recycled plastics, which underscores a troubling reality. Recycled plastics often exhibit higher detection frequencies and median concentrations of certain contaminants, particularly legacy additives like banned flame retardants. This contamination is attributed to cross-sectoral recycling—where plastics from one industry end up in another—and cross-temporal recycling, which introduces older, regulated chemicals into modern products.
For instance, the study highlighted the unintended transfer of brominated flame retardants from recycled electrical equipment into consumer products such as toys. Such findings raise urgent concerns about the health implications and the viability of recycling processes within a circular economy framework.
Applications and Future Directions
The database is designed to be a critical resource for exposure assessments, substance flow analysis, and policy development. Researchers and regulatory bodies can leverage this data to trace the movement and concentration of chemicals across different stages of the plastic lifecycle. This tool not only aids in understanding contamination pathways but also supports strategic planning to improve recycling practices.
However, the authors stress the need for more comprehensive analyses, particularly of recycled plastics and non-targeted studies. Future efforts should include broader sampling from under-represented regions and an expanded focus on non-intentionally added substances (NIASs), which remain elusive in many current studies.
Implications for Policy and Safety
The report’s findings call for enhanced transparency in the production and recycling of plastics. As pointed out, current regulations often fall short of addressing all hazardous substances, leaving gaps in safety for consumers and ecosystems. Clearer chemical reporting and the development of digital product passports could bridge these knowledge gaps, fostering safer production and recycling.
Helene Wiesinger, a lead author of the report, emphasized, “Without systematic data, it's difficult to transition to a truly safe and sustainable circular economy.” The LitChemPlast database is a foundational tool aimed at changing that, urging stakeholders to prioritize clean cycles in the recycling process and enhance safety protocols across industries.
