“Ambitious” efforts could set waste reduction targets, establish scientific advisory body
By Erik Stokstad - A version of this story appeared in Science, Vol 375, Issue 6583.
Each year, an estimated 11 million tons of plastic waste enter the ocean, equivalent to a cargo ship’s worth every day. The rising tide—in the oceans and beyond—is just a symptom of much wider problems: unsustainable product design, short-sighted consumption, and insufficient waste management, scientists say. To curb the flood, says Jenna Jambeck, an environmental engineer at the University of Georgia, “we need to take more action and it needs to be further upstream” in the production process.
That’s exactly what negotiators from 193 countries are setting out to do when they meet in Nairobi, Kenya, next week. Their ambitious goal: to create a negotiating committee that will try to hammer out, within 2 years, a new global treaty intended to curb plastic pollution.
An already released proposal, modeled on the United Nations’s climate treaty, would have nations adopt action plans, set binding waste reduction targets, and establish monitoring systems and a new global scientific advisory body. “It’s about time,” says Chelsea Rochman, an ecologist at the University of Toronto who has called on nations to tackle the issue.
Existing international efforts to reduce marine litter and exposure to hazardous chemicals include some measures related to plastic pollution. But no global treaty tries to reduce pollution by targeting a product’s entire life cycle, from its birth as a raw material to its death—if it becomes trash. Taking such a broad approach to plastics, says Anja Brandon, a policy analyst at the Ocean Conservancy, “is going to be a much bigger scientific endeavor.”
For one thing, rigorous, comparable numbers on the scope and sources of the problem are scarce, making it difficult to identify pollution hot spots or detect trends. Nonprofit groups and government agencies use dozens of varying protocols for surveying beach litter, for example. Methods of counting microplastics in water—shed from synthetic fabrics, for example, or formed when large plastic objects degrade—also vary. “There are several holes in the data,” Jambeck says.
The new treaty could help by promoting or establishing standard measuring and accounting methods. One such approach, called environmental economic accounting, is already being used in some countries to track various raw materials. And a method known as mass balance analysis, which tracks the amount of material entering and leaving production processes, holds promise for quantifying the amount of recycled plastic used in new products.
Even after scientists settle on standard metrics, collecting those numbers could be a challenge, Jambeck notes, especially in developing nations with relatively weak regulatory and research infrastructures. The United Nations Environment Programme (UNEP), which is hosting the upcoming meeting, has worked to increase monitoring capacity with training programs and online courses. Such efforts would be aided by a new treaty that encourages funding and technological advances. Remote sensing via satellites and drones, for example, could more easily identify plastic pollution trends, reducing the need for labor-intensive ground surveys.
More detailed industrial data on plastics production, transport, and consumption could also help nations curb pollution, researchers say. But many countries allow companies to keep such numbers private, making it difficult to calculate how plastic is moving through the economy and into the environment. And no one systematically tracks that information. The Ocean Conservancy, for example, has struggled to find out how much recycled plastic firms are using, Brandon says. Researchers are still pondering which numbers would be most useful, and how the treaty might help make that information more available.
Negotiators will also confront a key question: How much plastic pollution is too much? It’s clear that plastic bags, discarded fishing gear, and microplastics can kill wildlife, but scientists are just beginning to figure out how to calculate the risks. The treaty could help catalyze such efforts, says Rochman, who recently helped California regulators devise protocols for setting microplastic thresholds to protect people and ecosystems.
The political will to reduce plastic waste will be much higher if it’s known to harm humans, says Karen Raubenheimer, a policy researcher at the University of Wollongong. But she thinks any final agreement is unlikely to call for hard caps on new plastic. “It will be challenging in the short-term to stop using virgin plastic,” Raubenheimer says.
A big reason is that many uses of plastic are seen as essential. Single-use plastic items are common in health care, for example, to prevent contamination and infections, and in the food industry to keep fruit, vegetables, and other products from spoiling. Even disposable bottles can be vital in areas without clean water.
Negotiators might call for the reduction or elimination of what UNEP has called “unnecessary, avoidable and problematic plastic,” such as single-use shopping bags, takeout cutlery, or plastic beads in cosmetics. But analysts say nations must also focus on ways to reuse and recycle plastic materials. Currently, researchers estimate that less than 10% of plastic products are recycled. Smarter product designs that drive better waste management practices could boost that number, reducing the demand for virgin materials.
Trying to finalize the new treaty in just 2 years is “highly ambitious,” UNEP admits. But researchers who have watched the plastic pile up are delighted that the talks are even getting started. “People are putting high level resources to try to solve this problem in a way that we didn’t see a decade ago,” says Kara Lavender Law, a physical oceanographer at the Sea Education Association. “It’s actually astonishing.”