Untangling the chemical complexity of plastics to improve life cycle outcomes

A diversity of chemicals are intentionally added to plastics to enhance their properties and aid in manufacture. Yet the accumulated chemical composition of these materials is essentially unknown even to those within the supply chain, let alone to consumers or recyclers. Recent legislated and voluntary commitments to increase recycled content in plastic products highlight the practical challenges wrought by these chemical mixtures, amid growing public concern about the impacts of plastic-associated chemicals on environmental and human health. In this Perspective, we offer guidance for plastics manufacturers to collaborate across sectors and critically assess their use of added chemicals. The ultimate goal is to use fewer and better additives to promote a circular plastics economy with minimal risk to humans and the environment. Additives are essential to the diverse use of plastics, yet pose risks to health and recycling quality. Collaboration across supply chains, disclosure of composition and risks, and improved additive design can enable more sustainable plastics.