Approximately 8 million metric tonnes of plastic litter flow to the ocean annually, and only 9% of plastic waste ever produced has been recycled….Another major issue relates to microplastics – those plastics that are smaller than 5 millimeters, and that pose increasing environmental, economic and health hazards… Discarded plastics break down into these smaller particles through natural weathering processes. Microplastics can enter water bodies through different pathways, including atmospheric deposition, run-off from land, roads and through municipal wastewater.

A review of technical solutions from source to sea explores a set of innovative tech solutions. Among these potential technologies include:

• Introducing debris-cleanup boats, debris sweepers and sea-bins to remove plastics and other wastes carried into water bodies;
• Protecting large bodies of water by introducing wetlands along coastlines;
• Secondary and tertiary wastewater treatment which relies on membrane filtration to prevent microplastics entering rivers and lakes;
• Advanced coagulation technology to make water contaminated with microplastics drinkable;
• Promoting sustainable waste management practices to reduce plastic leakage.

A key principle of this work is preventing untreated wastewater, which is often packed with plastics and microplastics, from entering the environment in the first place.  The wastewater coming from urban residential, industrial and commercial settings is full of contaminants including plastics, microplastics and other debris…

Water pollution by plastics and microplastics: A review of technical solutions from source to sea, UNEP Press Release, Dec. 27, 2020