Pressure is slowly building in the U.S. against polystyrene foams and expanded polystyrene (EPS) – commonly known by the trademarked brand, Styrofoam – as communities and states begin to phase out its use due to sustainability-linked concerns.
A synthetic “aromatic hydrocarbon polymer,” polystyrene is the building block of what most people refer to as Styrofoam, and often takes the form of foam or EPS – a separate product made up of polystyrene beads that are injection-molded into custom shapes.
Regardless of the specific branding or exact chemical makeup, polystyrene foams are a well-known staple in the food packaging industry. The product’s light weight, low cost, water resistance, and insulation abilities all lend themselves to packaging for proteins like seafood, which needs to be kept cool and sanitary.
However, polystyrene products’ negative environmental impact has also been driving many areas across the U.S. and around the world to begin considering – and implementing – bans on the material.
The U.S. states of Maryland, Maine, and Vermont have all passed and enacted bans on polystyrene, with New York recently joining them as of 1 January, 2022. A ban in New Jersey is scheduled to begin on 4 May, 2022, and one in Colorado, passed by state voters, is set for 2024. The U.S. state of Florida, meanwhile, will consider rulemaking on banning polystyrene later in 2022, following a proposal from Florida Agriculture Commissioner Nikki Fried.
Some communities banned the use of the material by ordinance in certain situations: The town of Freeport, Maine, for example, has banned the use of polystyrene in food packaging and take-out containers since 1990.
Behind almost all of the bans – longstanding and recent – is a similar core motivation: Worry over the material’s long decomposition time and disposable nature. This, coupled with health concerns, has been prompting states to push for alternatives, according to Fried.
“Polystyrene may be convenient, but there is a hidden danger to public health from these disposable consumer products,” Fried said. “Chemicals in polystyrene are not only linked to human and animal health concerns, but because these petroleum-based products take at least 500 years to decompose, their negative effects continue long after they’re thrown away.”
For Oceana Florida Gulf Coast Field Representative Hunter Miller, at the crux of the issue is how fast the material will break down into “microplastics,” which then stick around for hundreds of years, impacting wildlife and affecting human health
“Polystyrene in particular is problematic because it breaks down into microplastics at an alarmingly fast rate,” Miller said.
Certain retailers have also begun to move away from the material as part of sustainability efforts. Wegmans, for instance, phased out all polystyrene foam egg containers in 2021 as part of its overall goal to reduce in-store plastic packaging by 10 million pounds by 2024.
The pressure, both from retailers and from the government, is already having an effect, according to Christa Biggs, the manager of business development for Aptar Food + Beverage’s food protection division.
Atlanta, Georgia, U.S.A.-based Aptar is one of the largest manufacturers of plastics in the world, and the company has been involved in efforts to reduce the use of plastics and increase the sustainability in the food-container sector.
Much of the waste in the U.S. food stream is at the retail level, Biggs said, and there are companies aiming to change that.
“They’re the ones I’ve seen on my end push for more-sustainable packaging,” Biggs said. “In terms of retail, and what I’ve seen from seafood customers a little more downstream, they are most focused on getting rid of that polystyrene foam from a sustainability standpoint.”
Aptar is one of many firms working on solutions to the issue – like the company’s SeaWell Protective Packaging System, which is designed to preserve seafood quality and freshness
Packaging is a complicated science requiring careful material engineering to ensure that products are kept fresh and safe in a convenient container, without costing an exorbitant amount, Biggs said. Raw proteins like seafood have challenges switching to alternative materials from plastic, she said.
“Raw protein packages are typically something that’s the most difficult to replace with something biodegradable,” Biggs noted.
Proteins are often wet, she said, and can cause biodegradable materials to decay at the same rate as the meat or seafood contained within them.
“The raw meats, proteins, seafoods … not only are they wet, but they’ve got their own nutrients in there, they’ve got their own chemical reactions going on,” Biggs said. “There’s a lot of things happening at a molecular level that the compostable stuff out there right now, they’re not robust enough to withstand and hold up and provide the same barrier properties.”
Many companies have switched to alternative forms of plastic products that don’t use polystyrene foam, often opting instead for polypropylene-based materials that cost slightly more but don’t have the same issues. Additionally, such polypropylene-based products are recyclable, a primary aim for modern packaging.
Biggs said for those companies that have switched, it isn’t as simple as changing the material – because of the properties of the different materials, for the most part, there is no one-to-one packaging solution.
“We’ve never made the same exact tray dimensions as the polystyrene world was making. I’ve never seen a direct comparison tray. It was never an easy switch,” Biggs said. “The dimensions have never translated over as a copy-paste.”
The newer plastics, made using thermoforming, have different requirements than the polystyrene foam, which means the same shapes and sizes don’t necessarily translate between the materials. The rounded edges of the foam trays, for example, aren’t something easily replicable with the other plastics, Biggs explained.
“If you think about those foam trays, a plastic tray has got a pretty sharp corner, almost 90 degrees,” Biggs said. “If you buy a pound of ground beef now, the tray inner dimensions are more like a 90-degree angle.”
Those changes in angle mean different volumes, which could impact the products inside. On top of that, literally, is the film that covers the product and package. For many foam-based containers, the common method of wrapping the product is an “overwrap,” which involves completely encasing the whole package in some form of clinging plastic film. The problem is that same film often isn’t usable with a new plastic tray, according to Biggs. Foam is often “stickier,” she said, allowing the film to actually cling to it. On the other hand, newer plastics will sometimes allow that material to fall off, or worse, interact at a molecular level with it in negative ways.
Current packaging uses a top-sealed lid instead, but that also requires careful consideration in terms of material, Biggs noted.
“A top-sealed lidding seal has to be compatible with the tray material,” she said, adding that the interaction between the two materials where they seal could vary. Moreover, the wrong materials mixed the wrong way could cause issues.
Even with well-matched materials, actually getting the product into the package can add further complexity to the process, Biggs said.
“Another thing is equipment. The people who were overwrapping before, if they had to change from a tray to a top seal, that’s a completely different piece of equipment,” Biggs said. “It’s extremely complicated. It’s never just an easy switch.”
Changing over an entire packaging line to move away from polystyrene foam isn’t necessarily as simple as swapping out one material for another, and any seafood packaging operation still using the foam may want to consider that before a ban forces a change, Biggs said.
In the future, there may be a replacement for polystyrene foam that meets all the same metrics – affordable, lightweight, and great at insulation, Biggs said.
“That’s where all the research efforts are,” she said. “There’s no other sustainable resource that can match all of those qualities.”
Photo courtesy of photosync/Shutterstock
