Should bioplastics be counted as compost? Debate pits farmers against manufacturers

Los Angeles Times

04-07-2025

Vernalis — Greg Pryor began composting yard and food waste for San Francisco in 1996, and today he oversees nine industrial-sized composting sites in California and Oregon that turn discarded banana peels, coffee grounds, chicken bones and more into a dark, nutrient-rich soil that farmers covet for their fields and crops.
His company, Recology, processes organic waste from cities and municipalities across the Bay Area, Central Valley, Northern California, Oregon and Washington — part of a growing movement to reduce greenhouse gas emissions by minimizing food waste in landfills.
But, said Pryor, if plastic and packaging manufacturers' get their way, the whole system could collapse.
At issue is a 2021 California law, known as Assembly Bill 1201, which requires that products labeled 'compostable' must actually break down into compost, not contaminate soil or crops with toxic chemicals, and be readily identifiable to both consumers and solid waste facilities.
The law also stipulates that products carrying a 'compostable' label must meet the U.S. Department of Agriculture's National Organic Program requirements, which only allow for plant and animal material in compost feedstock, and bar all synthetic substances and materials — plastics and most packaging materials — except for newspaper or other recycled paper without glossy or colored ink.
The USDA is reviewing those requirements at the request of a plastics and packaging industry trade group. Its ruling, expected this fall, could open the door for materials such as bioplastic cups, coffee pods and compostable plastic bags to be admitted into the organic compost waste stream.
Amid pressure from the plastics and packaging industry, the California Department of Resources Recycling and Recovery said it will await implementing its own rules on AB 1201 — originally set for Jan. 1, 2026 — until June 30, 2027, to incorporate the USDA guidelines, should there be a change.
Pryor is concerned that a USDA ruling to allow certain plastic to be considered compost will contaminate his product, make it unsaleable to farmers, and undermine the purpose of composting — which is to improve soil and crop health.
Plastics, microplastics and toxic chemicals can hurt and kill the microorganisms that make his compost healthy and valued. Research also shows these materials, chemicals and products can threaten the health of crops grown in them.
And while research on new generation plastics made from plant and other organic fibers have more mixed findings — suggesting some fibers, in some circumstances, may not be harmful — Pryor said the farmers who buy his compost don't want any of it. They've told him they won't buy it if he accepts it in his feedstock.
'If you ask farmers, hey, do you mind plastic in your compost? Every one of them will say no. Nobody wants it,' he said.
However, for manufacturers of next-generation, 'compostable' food packaging products — such as bioplastic bags, cups and takeout containers made from corn, kelp or sugarcane fibers — those federal requirements present an existential threat to their industry.
That's because California is moving toward a new waste management regime which, by 2032, will require all single-use plastic packaging products sold in the state to be either recyclable or compostable.
If the products these companies have designed and manufactured for the sole purpose of being incorporated in the compost waste stream are excluded, they will be shut out of the huge California market.
They say their products are biodegradable, contain minimal amounts of toxic chemicals and metals, and provide an alternative to the conventional plastics used to make chip bags, coffee pods and frozen food trays — and wind up in landfills, rivers and oceans.
'As we move forward, not only are you capturing all this material ... such as coffee grounds, but there isn't really another packaging solution in terms of finding an end of life,' for these products, said Alex Truelove, senior policy manager for the Biodegradable Product Institute, a trade organization for compostable packaging producers.
'Even if you could recycle those little cups, which it seems like no one is willing to do ... it still requires someone to separate out and peel off the foil top and dump out the grounds. Imagine if you could just have a really thin covering or really thin packaging, and then you could just put it all in' the compost he said. 'How much more likely would it be for people to participate?'
Truelove and Rhodes Yepsen, the executive director of the plastic institute, also point to compost bin and can liners, noting that many people won't participate in separating out their food waste if they can't put it in a bag — the 'yuck' factor. If you create a compostable bag, they say, more people will buy into the program.
The institute — whose board members include or have included representatives from the chemical giant BASF Corp., polystyrene manufacturer Dart Container, Eastman Chemical Co. and PepsiCo — is lobbying the federal and state government to get its products into the compost stream.
The institute also works as a certifying body, testing, validating and then certifying compostable packaging for composting facilities across the U.S. and Canada.
In 2023, it petitioned the USDA to reconsider its exclusion of certain synthetic products, calling the current requirements outdated and 'one of the biggest stumbling blocks' to efforts in states, such as California, that are trying to create a circular economy, in which products are designed and manufactured to be reused, recycled or composted.
In response, the federal agency contracted the nonprofit Organics Material Review Institute to compile a report evaluating the research that's been conducted on these products' safety and compostability.
The institute's report, released in April, highlighted a variety of concerns including the products' ability to fully biodegrade — potentially leaving microplastics in the soil — as well as their tendency to introduce forever chemicals, such as per- and polyfluoroalkyl substances (PFAS), and other toxic chemicals into the soil.
'Roughly half of all bioplastics produced are non-biodegradable,' the authors wrote. 'To compensate for limitations inherent to bioplastic materials, such as brittleness and low gas barrier properties, bioplastics can contain additives such as synthetic polymers, fillers, and plasticizers. The specific types, amounts, and hazards of these chemicals in bioplastics are rarely disclosed.'
The report also notes that while some products may break down relatively efficiently in industrial composting facilities, when left out in the environment, they may not break down at all. What's more, converting to biodegradable plastics entirely could result in an increase in biodegradable waste in landfills — and with it emissions of methane, a powerful greenhouse gas, the authors wrote.
Yepsen and Truelove say their organization won't certify any products in which PFAS — a chemical often used to line cups and paper to keep out moisture — was intentionally added, or which is found in levels above a certain threshold. And they require 90% biodegradation of the products they certify.
Judith Enck, a former regional Environmental Protection Agency director, and the founder of Beyond Plastics, an anti-plastic waste environmental group based in Bennington, Vt., said the inclusion of compost as an end-life option for packaging in California's new waste management regime was a mistake.
'What it did was to turn composting into a waste disposal strategy, not a soil health strategy,' she said. 'The whole point of composting is to improve soil health. But I think what's really driving this debate right now is consumer brand companies who just want the cheapest option to keep producing single-use packaging. And the chemical companies, because they want to keep selling chemicals for packaging and a lot of so-called biodegradable or compostable packaging contains those chemicals.'
Bob Shaffer, an agronomist and coffee farmer in Hawaii, said he's been watching these products for years, and won't put any of those materials in his compost.
'Farmers are growing our food, and we're depending on them. And the soils they grow our crops in need care,' he said. 'I'll grow food for you, and I'll grow gorgeous food for you, but give us back the food stuff you're not using or eating, so we can compost it, return it to the soil, and make a beautiful crop for you. But be mindful of what you give back to us. We can't grow you beautiful food from plastic and toxic chemicals.'
Recology's Pryor said the food waste his company receives has increasingly become polluted with plastic.
He pointed toward a pile of food waste at his company's composting site in the San Joaquin Valley town of Vernalis. The pile looked less like a heap of rotting and decaying food than a dirty mound of plastic bags, disposable coffee cups, empty, greasy chip bags and takeout boxes.
'I've been doing this for more than three decades, and I can tell you the food we process hasn't changed over that time,' he said. 'Neither have the leaves, brush and yard clippings we bring in. The only thing that's changed? Plastics and biodegradable plastics.'
He said if the USDA and CalRecycle open the doors for these next-generation materials, the problem is just going to get worse.
'People are already confused about what they can and can't put in,' he said. 'Opening the door for this stuff is jut going to open the floodgates. For all kinds of materials. It's a shame.'