As we move closer to a future without plastic, what alternatives will take its place?

In March 2022, 175 countries agreed to work on a global treaty to combat plastic pollution. The ultimate goal is to finalize a document by the end of 2024 that effectively reduces plastic pollution, much like the Paris Agreement addresses climate change. The fourth and next-to-last negotiating session has just concluded in Ottawa, Canada, and some progress has been made on drafting the final agreement. Now, all eyes are on the final meeting, set to take place in Busan, South Korea, beginning on November 25.

Each year, 460 million tons of plastic are produced, according to the Organization for Economic Cooperation and Development (OECD), yet only 9% is properly recycled. Also, 22%—over 100 million tons—ends up in landfills or is burned uncontrollably. Despite being aware of the harmful effects of plastic on the environment and human health, we rely heavily on this vast family of materials for numerous applications. If nothing changes, OECD estimates indicate that by 2060 global plastic production could exceed 1.2 billion tons annually.

As nearly every nation worldwide debates how to reduce plastic use, curb pollution, and improve recycling rates, one question is gaining traction: what alternatives will we use? Finding replacements for plastic is more complicated than it may seem.

In line with most international negotiations, the 175 countries discussing a global plastics treaty are working from an initial document known as the zero draft. This document outlines the negotiation framework and specifies the areas to be addressed in the final treaty. These include measures to reduce pollution throughout the plastic lifecycle, limit chemical additives, and establish new rules for the use of microplastics and recycled materials. It also discusses potential alternatives to plastic.

The UN's initial document categorizes materials with the potential to replace plastic into two groups: substitutes, which include materials not based on fossil fuels or synthetic polymers, and alternatives, such as bioplastics and biodegradable plastics.

Many plastic alternatives, like glass, paper, and natural fiber textiles such as cotton, have been used for much longer than plastic itself. The UN report The Pressing Case for Natural and Environmentally Friendly Substitutes to Plastics also highlights alternatives like plant-based textiles, agricultural plastic substitutes made from wood waste, food packaging crafted from plant by-products such as banana leaves, and high-strength alternative fibers derived from sources like coconut.

Among the success stories in the development of new materials, the report highlights Bananatex, a technical textile fiber developed by the Swiss company QWSTION in the Philippines using banana plants; Calida, a Swiss company producing underwear and pajamas that incorporates fibers made from algae, bamboo, and cellulose into its fabrics; and Biopencil, a startup from Peru that has created materials based on marine algae for pencil production.

In recent years, the plastics industry has shown significant interest in developing bioplastics as an alternative to conventional plastics. However, the term encompasses a variety of bio-based materials, derived from renewable resources like sugar cane or corn-based ethanol. Notably, these alternative materials are not always biodegradable, and some petroleum-based plastics do have the ability to degrade. One of the most promising bioplastics is polylactic acid (PLA), which is plant-based, closely resembles traditional plastic, and is increasingly used for packaging. It is biodegradable under certain conditions.

Another material highlighted in the UN report is biodolomer, a biodegradable polymer of biological origin composed of a degradable polyester combined with calcium carbonate and vegetable oils. Biodolomer is being used to replace plastic-based fishing nets, among other applications, as part of a pilot project by the Sustainable Manufacturing and Environmental Pollution Programme in South Africa, Kenya, and Tanzania.

Bioplastics have significant potential to substitute for some traditional plastic applications. Yet, in 2023, they made up only 0.5% of the more than 400 million tons of plastics produced globally, according to the European Bioplastics organization. Their limited production capacity and higher cost compared to petroleum-based plastics are major challenges. There is no single solution to replace plastic: alternative materials are just one component of a broader global effort that includes reducing plastic use, reusing and repairing products, limiting the most harmful applications, and improving recycling rates.