The lifecycle of plastics – an evolving research field
This text summarizes key findings from the research chapter “The role of recycling and biodegradable materials in aquaculture and fisheries” in the book Managing Marine Plastic Pollution in Norway.
The research highlights that there is no single solution to the plastic challenge in the seafood industries. To reduce the plastic footprint, materials need to be integrated into more circular systems – where design, use, collection and recycling are better aligned.
Biodegradable materials are also considered a potential complement to recycling, particularly in situations where loss or wear is difficult to avoid. At the same time, challenges remain related to durability, cost and the lack of standardized testing methods.
Bringing plastics back into the loop
Recycling works best when plastics are clean and consist of a single polymer.
Materials such as HDPE – commonly used in floating pipes – can often be mechanically recycled. Nets made of polyamide (PA) can be recycled through chemical processes, where the material is broken down and rebuilt into high-quality polymers.
Circularity is therefore possible – but only under specific conditions related to material choice, design and handling.
At the same time, research shows that plastic emissions do not only occur when equipment is lost. Wear and tear during use can also lead to the release of microplastics into the marine environment.
The challenge starts with design
Many of the challenges related to plastic recycling originate already in the design phase.
Fishing gear can contain large amounts of plastic, but is often made from multiple materials that are difficult to separate. Ropes and mooring systems typically consist of several types of plastics, and may also include metal components or additives.
Such combinations make dismantling and material recovery technically complex and costly. As a result, much equipment is in practice difficult to recycle.
The challenges associated with plastics therefore do not begin when products become waste – but in how they are designed.
Logistics: the hidden bottleneck
Logistics is another key challenge.
Plastic waste from fisheries and aquaculture is generated along large stretches of coastline, while recycling facilities are often centrally located. Long transport distances, small volumes and a limited number of actors capable of handling multiple plastic types make it difficult to establish stable recycling systems.
At the same time, there are examples showing that this can work. Experiences from, among others, Iceland demonstrate that extended producer responsibility schemes and improved dismantling systems can contribute to more efficient recycling.
Plastics are shaped on the drawing board
Fishing and aquaculture equipment often consists of complex material combinations, making it difficult to establish clean plastic streams for recycling.
At the same time, solutions exist for several types of plastics – provided that materials are designed with circularity in mind.
The key conclusion is therefore that the environmental footprint of plastics is largely determined long before products become waste. Choices related to materials, product design and systems for collection and recycling set the conditions for how circular plastic use canbecome.
This research summary is based on the chapter “The role of recycling and biodegradable materials in aquaculture and fisheries” in the book Managing Marine Plastic Pollution in Norway. The chapter is authored by Christian W. Karl Fredrik K. Mürer, Hanne H. Hatlebrekke, Eduardo Grimaldo, Haraldur Einarsson, Roger B. Larsen and Eli F. Ullern. The work was primarily carried out as part of SHIFT-Plastics, with contributions from research activities within SFI Dsolve.