More than 29 million metric tons of plastic enters the environment each year, where it harms animals and damages habitats. A study co-authored by researchers at The Pew Charitable Trusts and published in Science on July 23 has found, however, that this flow can be reduced by nearly 80% in the next 20 years using existing waste management and recycling technology.
To achieve this reduction, significant changes are needed in how countries manage plastic waste—both upstream (production and design) and downstream (use and disposal). The changes include reducing plastic use, substituting plastic where possible, improving recycling strategies, expanding waste collection, and building better disposal facilities.
Even with immediate and concerted action, however, the study found that 710 million metric tons of plastic waste would enter aquatic and terrestrial ecosystems between 2016 and 2040.
“Although the technology exists to address much of the plastic waste challenge, the infrastructure and business processes are not yet in place,” said Winnie Lau, a senior officer with Pew’s preventing ocean plastics project and lead author of the study. “Substantial investment in collection infrastructure, plastic substitutes, and recycling facilities needs to occur before we will be able to see real change.”
Increasingly, research is showing the negative effects of plastic pollution on wildlife. More than 800 species are known to have been harmed by this pollution, either through ingestion or becoming entangled. Humans also are affected. Drink bottles and other plastic waste litters beaches, blocks drains and other wastewater systems, and provides a breeding ground for disease vectors. The combined economic cost of plastic pollution on fishing, tourism, and shipping is estimated to be at least $13 billion annually.
The rapid increase in plastic pollution in the past few decades is due in part to an increase in single-use plastic consumption and a growing throwaway culture. In addition, most waste management systems globally lack the capacity to safely dispose of or recycle the quantity of waste plastic being generated.
Because plastic is so ubiquitous, no single global strategy exists to address this pollution. The diversity of plastic types also makes it difficult to effectively address the problem: Although rigid plastic dominates recycling, flexible and multimaterial plastic waste should be tackled using other strategies.
To gauge the potential for different strategies to reduce plastic pollution, the researchers developed a model to calculate the flow of plastic through its production, use, recycling, and disposal. The model estimates the quantity of plastic waste inputs into the environment and was used to evaluate the effects of five scenarios: business as usual; improving collection and disposal; increasing recycling; reducing plastic use and substituting alternatives; and system change, which integrates all of these interventions.
It shows that system change would reduce annual rates of aquatic and terrestrial plastic pollution by nearly 80% compared with the current trajectory by 2040. Such an overhaul would also cut the production and consumption of newly produced plastic by 55%. If manufacturers shifted to alternative materials, such as paper and compostable materials, and ensured that products and packaging were designed for recycling, the amount of recyclable plastic would not only rise, but increase in value.
To achieve the nearly 80% reduction, global recycling capacity would need to double, and middle- and low-income countries would need to expand waste collection rates. Strategies focused solely on downstream solutions (collect and dispose, or recycling) make meaningful reductions in annual plastic pollution rates (56.1% and 31.7% by 2040, respectively), but do not get close to solving the problem. Meanwhile, strategies focused solely on upstream solutions (reduce and substitute) also lead to significant but not full reductions in annual pollution rates (55.6% by 2040).
Implementing a system change is not cost prohibitive. In fact, due to reduced plastic production, increased recyclability and other changes, the researchers estimate that global net waste management costs would be about 18% lower.
Unfortunately, a significant accumulation of plastic waste will continue, even under the system change scenario. Innovations, such as new business models and advanced waste management technologies, and commitments from the international community will be needed to eliminate the flow of nearly all plastic pollution into the environment.
The Pew Charitable Trusts provided funding to support this research.
Jim Palardy is a project director with The Pew Charitable Trusts’ conservation science project.