The physical properties of biocarriers, particularly their density close to that of water, make them highly mobile pollutants with the capacity for rapid dispersion in the aquatic environment and all the more difficult to contain.
Solutions available
Reducing risks at the source remains the most efficient solution for addressing plastic pollution. The guidelines follow the biocarrier’s life cycle, from WWTP design to the final usage or disposal of biocarriers. There is a broad scope of action to resolve the issue of biocarrier pollution.
Interviews of stakeholders involved in different stages of the biocarrier life cycle identified risk-mitigating measures, either already implemented or requiring implementation from scratch. These measures vary from regulatory oversight to technological upgrades to improvements in crisis management plans. To reach the objective of reduced biocarrier leakage, the mobilization of all stakeholders is essential to ensure that this type of pollution is considered in relation to its environmental impact. The implementation of preventive measures and the securing of wastewater treatment systems also appeared as key steps to effectively reducing the risk of leakage.
The recommendations in this document focus on biocarriers. However, it would be relevant to extend their application to the 3 types of plastic supports mentioned above, given the similarity of their physical properties and use.
International Cooperation
The report will contribute to policy development between the Nordic countries and to identify and follow up on possible areas for further cooperation and collaboration.
It will also advance the United Nations Environment Assembly (UNEA) resolution 3/7, which stresses the long-term ambition of eliminating the discharge of plastic litter and microplastics into the oceans and to UN Sustainable Development Goals 14.1.
Furthermore, this document represents a contribution to the work of the Convention for the Protection of the Marine Environment of the North-East Atlantic (more commonly known as the OSPAR Convention) in relation to its objective on marine litter, namely "to reduce substantially the amount of marine litter in the OSPAR maritime area to levels where its properties and quantities do not cause harm to the marine environment".
Even if these guidelines are initially addressed to Nordic Countries, it should be noted that although each WWTP has its own environmental specificities the core of the issue remains the same wherever its location. Therefore, these recommendations apply to a wide range of facilities.