Defining a ‘Circular Bioeconomy’: How Recent Policy Promotes a Shift in the Future of US Plastics Manufacturing

For some, the decision by the Biden Administration to enact the Executive Order on Advancing Biotechnology and Biomanufacturing came as a welcome surprise. Drawing inspiration from the remarkable strides made by biotechnology to quickly develop effective COVID-19 vaccines, the order broadcasts an intent to leverage government expertise and resources to pave the way for a groundbreaking transformation in U.S. product development and manufacturing.

According to the Federation of American Scientists, many industry leaders agree that this directive was the first step towards building a U.S. "bioeconomy" — i.e., laying the groundwork for the government to best support the rise of biotechnology, biomaterials, and bioplastics positions. But what exactly is a bioeconomy, and how does it fit into the United Nations Environmental Programme (UNEP) global plastics treaty?

Bioplastics and the ‘Circular Bioeconomy’

"The plastics circular economy’s three tenets: eliminate, innovate and circulate, offer a new vision of a sustainable future. This means that we should strive to eliminate plastic products we don’t need; innovate, so all plastics that we do need are designed to be safely reused, recycled or composted; and circulate everything we use to keep it in the economy and out of the environment." — Jyoti Mathur-Filipp, Executive Secretary of the Intergovernmental Negotiating Committee (INC) Secretariat, UNEP, Plastic Treaty Progress Puts Spotlight on Circular Economy

The concept of a "circular bioeconomy" describes an economic model that emphasizes circularity, sustainability, and the incorporation of bio-based inputs in the materials economy. Focusing specifically on plastics, a study published last December in Nature, “Plastic Futures and their CO2 Emissions,” uses predictive modeling to compare the potential impacts of various strategies for curbing carbon emissions, and highlights the potential of the circular bioeconomy to significantly reduce cumulative carbon emissions.

The Nature study profiled the results of applying an assessment model to the entire carbon cycle of plastics, from “upstream chemical production to downstream production of plastic polymers, their transformation into plastic products, their use in different sectors, and their end of life.” Earmarking 2 degrees Celsius global warming by 2100 as the upper limit, the model attempts to predict the net effect of increasing carbon taxes to incentivize recycling, of transitioning from petroleum plastics to bioplastics, and of altering the energy mixes and end-of-life destinations of plastics. Of the four predictive models presented, the circular cioeconomy (CBE) model — with maximum recycling, elimination of incineration and reduction of landfilling, overall consumption reduction, and maximum biomass integration — shows the greatest cumulative carbon emission reduction.

Biological and Petroleum Blends: ‘Mass Balance’

New materials are expensive to develop and can take decades to commercialize. One way chemical manufacturers have been integrating bioplastics into petroleum plastics manufacturing and renewable feedstocks into chemicals manufacturing is to create workable blends of the two. For bioplastics, this can be as straightforward as blending raw biomass like hemp or other cellulosic byproducts into petroleum plastics, or as refined as integrating renewable feedstocks at the chemical input stage. In some cases, petrochemicals with beneficial attributes like biodegradability and low or no toxicity are used in conjunction with biopolymers to make everyday products like compostable films and bags.

Using these materials can allow brands, using a method called “mass balance,” to credit themselves for using some percentage of renewable feedstock in their final products. For some applications mass balance has made it possible to wean an industry off petroleum while bioplastics innovators build capacity. It's clear however that mass balance must be a short interim step in the transition to a circular bioeconomy.

When we look at the projected growth in demand for plastics, introducing partially bio-based solutions will prolong our dependence upon oil and incentivize the expansion of petro industries, not to mention the continued output of life-damaging chemicals and our dependence on landfills.

After Use

We consume around 40 percent of all plastic as packaging, and a large majority of packaging is disposed of within a year. Because packaging is often lightweight, soiled after use, and made of a mix of materials, only approximately 9 percent of all plastic is recycled each year — the rest is incinerated, landfilled or escapes into the environment. To address these issues specifically, bioplastics designed to compost at end of life entered the market in the early 2000s in the form of polylactic acid (PLA), which is a relatively stable compostable material made from plant starches. PLA is commercially compostable, meaning it will be consumed by microorganisms that live in and create soil in less than 90 days if the soil is maintained at a specific temperature and moisture level.

Initially marketed as a sort of magic eraser of waste, compostable bioplastics suffered setbacks in the single-use packaging sector as composting authorities struggled with nonstandardized inputs and inaccurate labeling. Recycling programs meantime failed to such an extent that the U.S. started shipping millions of pounds of its plastic waste overseas in an attempt to get it out of sight. A paradigm shift was in order across the board: We needed to radically reduce consumption of plastic, period, and design the plastic we did use so that it could and most likely would be re-circulated.

Transparency and the Upside of Certifications

The U.S. recognizes several bioplastic specific certification standards designed to confirm both the integrity of the original material(s) and the best case after use designation for the product. For straightforward bio-based product certification, the USDA can provide a 100 percent bio-based or BioPreferred stamp of approval. For compostable bioplastics, ASTM standards generally mirror those in the EU and Australia, but U.S. testing infrastructure has yet to catch up.

U.S.-based Biological Products Institute, or BPI, partners with Germany-based Din Certco to grant Certified Commercially Compostable status to products and packaging in the U.S. Certified Home Compostable status can be obtained through overseas certifiers — Din Certco, TUV to name two. To achieve certification, products are infrared checked periodically during certification, and the material itself must be lab analyzed for toxins such as heavy metals and PFAs (flourines) before certification can be granted.

Entities like BPI work with municipal composting networks and the US Composting Council (USCC) to perform real-time product testing and interrogate the distance between stated claims and experience at the compost production level. The Compost Manufacturing Alliance, for example, represents a national alliance of private and municipal composters committed to working with compostable product brands by performing field tests, item by item, and providing certifications for each compost method.

If this process seems daunting, it is, but the upside from my point of view is that we're subjecting bio-based products and materials to a level of scrutiny never afforded petroleum plastics at their inception. The bar for achieving third-party compostable certification is high because compostable products aren't designed to be entombed in landfill, but to be recirculated as compost.

Unintended Consequences

Bio-based products have different performance parameters and processing requirements than petroleum products, and lack the substantial subsidies and lobbying infrastructure in place for petroleum plastics. Today, bioplastics tend to be more expensive than petroleum plastics. Furthermore, we run bio-based materials through machines that have been running petroleum plastics for decades, in factories that use toxic chemicals and additives to increase productivity (and decrease cost).

PFAs, or Per and Polyfluoroalkyl substances are a case in point. Banned under one name — Teflon — in 2013, PFA manufacturers slightly modified their formula and flooded the market with nonstick additives and coatings under new names. Plant fiber containers and paperware are traditionally lined with petroleum plastic to prevent leakage. When bio-based container brands and their customers requested plastic-free containers that didn’t discolor with food oils or absorb liquid, manufacturers reached for PFAs. An interrogation of compostable food container ingredients by the Counter (formally the New Food Economy) put the conversation around PFAs back in the news. Today, both at the state and federal level, bans, lawsuits and cleanups are underway. PFAs are in firefighting foams, feminine pads, thick markers and waterproof clothing, but it was the scrutiny brought to bear on compostable bio-based dishware that shone a light on the larger public health issue.

Bioplastics Today: PHA

While PLA developers like Natureworks benefited from (and suffered) first mover advantage, bioplastics innovators initiated research in a variety of avenues: e.g., algae, fungi, milk proteins, spider silk, chitin (seafood shell waste), nut shells, biomass cracking, hemp, fermentation, cellulose. Fermentation is yielding scalable success in a number of areas, including in the production of PHA. PHA, or polyhydroxyalkanoate, is a biopolymer notable for its ability to biodegrade in almost any environment, and is made by fermenting carbon-rich feedstocks (often seed oils) with soil bacteria.

A sort of bacterial energy reserve, PHAs can be made in more than a hundred different molecular structures, each with its own properties and benefits. The first U.S. company to launch PHA, Metabolix, failed in 2016, two years after partnering with Archer Daniels Midland to commercialize PHA. The stated reason? Lack of customers. Today, seven years after Metabolix sold its assets to South Korean food giant CJ CheilJedang, the U.S. bioplastics materials market includes PHA from Danimer Scientific and RWDC Industries in Georgia, PHBH from Kaneka Biopolymers in Texas, and PHBs from Mango Materials and Newlight Technologies in California. Mango Materials and Newlight Technologies are both commercializing the building blocks of PHB resins that are made by feeding methane to bacteria, hence "closing the loop" at inception.

The initial impulse for many brands venturing into product development with PHAs is to make a straw. Straws, so perfectly vilified in the December 2017 episode of BBC’s Blue Planet II, are a red herring for a much bigger plastic pollution problem. The list of target product categories for PHAs include textiles, tires, cosmetics, marine fishing and fish farming gear, and agricultural mulch films. PHAs, PHBs and PHBH are finding niche applications in cosmetic bead coatings, mulch films, textile threads, medical sutures and implants, fishing gear, and filter components, to name a few, as well as high volume single- and limited-use applications like cups, food wrappers and straws.

Meanwhile, PLA, now an established biopolymer manufactured both in the U.S. and worldwide at commercial scale, is being blended with PHAs to create compounds with the performance benefits of PLA and the biodegradability benefits of PHA.

Disruptions caused by COVID-19 shutdowns forced nations to address their reliance on global supply chains. This could result in a net win for U.S. manufacturers open to working with new materials. During the shutdown Better for All pivoted from manufacturing in China to developing with PHBH in the United States. We've been here since. Being close to our manufacturer made it possible for us to discover technological innovations like iMFLUX’s software-hardware update to injection molding machines, designed to regulate pressure during injection in real time, with significant benefits for processing bioplastics, reducing energy demand, and part loss.

Looking Ahead: Embracing a Bioeconomy

To make the necessary transition to a truly circular bioeconomy, we need infrastructure that can properly manage both the petroleum plastics already circulating in the economy and the new biomaterials introduced to replace them. We need to design for less, design materials-first, and cultivate an array of renewable inputs. We need a robust U.S. manufacturing sector ready to embrace myriad energy efficiencies, automation, and systems designed to recirculate rather than dump. We need to cultivate generations of biologists and chemists tasked with understanding and even unlocking the secrets of the cellular powerhouses in the world around us. And we need to take our cues from those organisms, building systems in which everything has its place and nothing goes to waste.

Finally, we must radically reduce our use of single-use packaging and find ways to build workable reuse systems, which will require a complete rethinking of the way we deliver and consume food, drink, clothing, home and personal care products. This economy will be circular and foreground a wide variety of bio-based inputs, materials and technology.

Raegan Kelly is the head of product and sustainability lead at Better for All, fully certified home and commercially compostable PHBH cups for large capacity venues, arenas, festivals and more.