Whereabouts of most Dutch plastic waste surprisingly unclear

Several hundred million kg of Dutch plastic waste remain off the radar. That applies to both plastic waste within the Netherlands and Dutch plastic waste that is exported to other countries. Researchers from Utrecht University and other organisations report this finding after mapping waste streams in the Netherlands. They call for better tracking of waste streams to curb global plastic pollution. The study recently appeared in the scientific journal Waste Management & Research.

In order to prevent plastic waste from entering the environment, it is necessary to trace the source of plastic waste that is not properly managed. A research project initiated by Utrecht University’s strategic theme Pathways to Sustainability aimed to map the complete chain of events that any piece of Dutch plastic waste undergoes: from the moment that it becomes waste to the point where it ends up. Much of it remains unknown.

It is only with the right data that regulators can track what happens to plastic waste and prevent it from ending up in the environment

Knowns and unknowns

Physical oceanographer Delphine Lobelle and her team aimed to gain insights into the amount of Dutch plastic waste that is generated, the amount ending up in the environment and to find out how this happens. The researchers identified thirteen categories of waste sources, of which the two most apparent were household plastic waste (such as food packaging) and textiles (like clothing). Plastic waste coming from the identified sources mostly ended up in Dutch facilities for incineration (destruction), recycling or was sent for export.  

However, the team discovered that a lot of data on waste management is simply missing, and that a lot is still unclear about the way that Dutch plastic waste is managed in the Netherlands and abroad. The researchers therefore decided to broaden their scope: not only would they map what was known, but they would also report about the unknowns surrounding Dutch plastic waste. Lobelle explains: “We realised that we couldn’t complete the story. Chunks were missing, and instead of trying to piece them together, we decided to make it part of the focus. Let’s bring out the missing data pieces and make sure that those who can help to fill those gaps, are aware of it.”

Plastic waste trade

The most notable unknowns concern the international trade of plastic waste. This is illustrated by the finding that the amount of plastic scraps imported into the Netherlands was almost half the total amount of plastic waste produced in the country. However, centralised reports on how this plastic waste is managed once entering the Netherlands don’t exist. Concerning waste exported from the Netherlands, the study revealed a lack of third-party audits in recycling plants abroad to ensure the proper recycling and management of Dutch plastic waste.

Management and mismanagement

In their project, the researchers used two techniques. They performed a material flow analysis, a method used to keep track of where a material comes from and where it goes over a certain period of time. Focusing on the year 2017, the study analysed plastic waste streams originating from multiple sources: plastic waste from Dutch households, different economic sectors and plastic waste that was imported from abroad. According to the researchers, proper management then consists of officially reporting what happens to the plastic waste, e.g. recycling, and making sure that the actions are implemented as intended.

Regularly keeping track of waste using methods like material flow analysis is essential to grasp the scale and progression of the plastic waste issue

The researchers also identified the ways in which Dutch plastic waste was not properly managed. They estimated the extent of mismanagement based on datasets of plastic litter collected on Dutch riverbanks and beaches. Looking across the Dutch borders, they additionally estimated amounts of Dutch plastic scraps entering foreign environments due to inadequate management in importing countries.

Policy and regulations

Lobelle emphasises the need for international regulations and laws with regard to plastic waste management. Additionally, every country should report how much of their imported waste is actually recycled. The current study could help policymakers identify where the biggest efforts need to be focused, says Lobelle. “By pinpointing these unknowns, we can steer research and policy into the right direction. That is why we widened the scope of this research to knowns and unknowns of plastic waste in the Netherlands. Once you have the full story, you can prevent plastic waste from reaching the environment.”