Although plastic is one of the most commonly used materials in our everyday life, the current linear economy ('produce, use and dispose') engenders high risks to human health in relation to greenhouse gas (GHG) emissions and environmental pollution. As a response to these challenges, the circular plastic economy is gaining momentum, where the goal is to reduce, reuse and recycle all plastic. The transition to the circular economy should be made across the entire plastics value chain in order to ensure circular design, production, use and waste management. This study examines the current scientific literature in relation to the entire value chain of plastics. This aim of the article is to provide an overview of the existing research (and highlight research gaps) associated with the transition of plastic use to a circular model. The literature was divided into the following categories: 1) design; 2) production; 3) use; 4) end-of-life; and 5) value chain. A high proportion of the literature was found to address the end-of-life phase, suggesting that the other phases are currently neglected. The results have implications that are applicable to multiple phases; in particular, contamination of waste streams and composite materials places significant limitations on the opportunity to recycle and reuse plastic in new products. This calls for changes in the whole value chain, and for trans-sectorial collaboration to ensure systemic transparency. Therefore, future research should take a holistic approach to the transition to circular through careful mapping of implications, stakeholder involvement and collaboration.

Plastic pollution is considered one of today’s major environmental problems. Current land-based monitoring programs typically rely on beach litter data and seldom include plastic pollution further inland. We initiated a citizen science project known as the Mass Experiment inviting schools throughout The Danish Realm (Denmark, Greenland and the Faeroe Islands) to collect litter samples of and document plastic pollution in 8 different nature types. In total approximately 57,000 students (6–19 years) collected 374,082 plastic items in 94 out of 98 Danish municipalities over three weeks during fall 2019. The Mass Experiment was the first scientific survey of plastic litter to cover an entire country. Here we show how citizen science, conducted by students, can be used to fill important knowledge gaps in plastic pollution research, increase public awareness, establish large scale clean-up activities and subsequently provide information to political decision-makers aiming for a more sustainable future.

Microplastics (MP) are contaminants of environmental concern partly due to plastics ability to sorb and transport hydrophobic organic contaminants (HOC). The importance of this “vector effect” is currently being debated in the scientific community. This debate largely ignores that the co-exposures of MP and HOC are mixtures of hazardous agents, which can be addressed from a mixture toxicity perspective. In this study, mixture effects of polyethylene microbeads (MP) and triclosan (TCS) (a commonly used antibacterial agent in cosmetics) were assessed on the marine copepod Acartia tonsa. Data indicated that MP potentiate the toxicity of TCS, illustrating the importance of understanding the mixture interaction between plastics and HOC when addressing the environmental importance of the vector effect.

The interest in tire wear particles (TWPs), generated from abrasion of tires, have gained traction over the past few years, both in regards to quantifying particulate emissions, leaching of different compounds, toxicity, and analytical methods. The life of a tire, from cradle to end-of-life, crosses over different scenarios during its lifetime and transcends environmental compartments and legislative areas, underlining the need for a collective approach. Sustainability for a tire encompasses the use of raw materials, recycling of raw materials, circular economy and material sourcing. The tire industry is currently making significant efforts towards a greener and more sustainable production considering reduction of CO₂-emissions, recycling, material sources and implementing the use of biomass from plants rather than oil-derived alternatives. In this paper, we aim to analyze and discuss the need for environmental regulation of tires in order to provide a series of targeted recommendations for future legislation. Our study shows that the numerous regulations related to tires focus on chemicals, manufacturing, raw materials, use of tires on roads, waste handling, safety and polycyclic aromatic hydrocarbons (PAHs) in different life cycle stages of a tire. However, none directly addresses the contribution of TWPs to the environment. Despite the overall good intentions of the existing regulations, there is a lack of focus on the compounds that partition from the tire and disperse in the environment, their mixture effects, and the transformative products from the parent compounds in the environment. Therefore, a renewed focus is needed on risk assessment of complex mixtures like TWPs. Thus, transparency in regard to use of chemicals in TWP, mixtures, minimization of emissions, and capture of particulate pollution should be a priority.