In theory, expanded polystyrene (EPS) is recyclable. But there are few places where that’s easy to do, and it's not at all possible through kerbside collections. That means this inorganic, hard-to-recycle plastic often ends up in landfills, or worse, waterways and the ocean.
As part of efforts to reduce waste and eliminate hard to recycle plastics in both New Zealand and Australia, expanded polystyrene is being phased out of use. The goal is to replace EPS completely from ‘business to consumer’ goods by 2025 in both countries.
If you use expanded polystyrene in your business, what could you replace it with that will provide a sustainable but functionally comparable solution?
In this article, we explore the issue with EPS, the available alternatives and how they weigh up as suitable solutions.
The problems with expanded polystyrene
EPS has been used widely to package fragile products since the 1950s. As a lightweight, durable material that's easy to mould into all sorts of shapes, it became a popular choice to pack and safely transport a range of products. If you’ve ever bought fragile items online; a toaster, a computer or a bathroom vanity, chances are, it has come packaged snugly in an EPS mould or floating safely around in eps packing peanuts.
But there are significant environmental issues with expanded polystyrene.
First, it's made from the petrochemicals Styrene and Benzene, both byproducts of the fossil fuel industry. Secondly, the virgin material used to make EPS, polystyrene beads, are shipped from offshore manufacturers across the oceans. Once the beads arrive, they’re ready to be expanded into EPS using a blowing agent such as pentane, another byproduct of the petroleum and gas industry. Pentane may not be a long lasting emission in the atmosphere but it takes a lot of energy to blow it into the polystyrene beads and expand them.
But the biggest problem of EPS is its end of life - or more to the point, its ever-lasting life.
As a synthetic material, expanded polystyrene cannot be naturally reintroduced to the biological cycle of the earth. That means, it goes on and on and on, and as it breaks down into smaller and smaller pieces, it can leach those chemicals Styrene and Benzene back into the environment as well as be consumed by animals, and us.
New options, ready now
The good news is that there is a growing number of alternative solutions that can help us kick our dependency on expanded polystyrene.
Broadly speaking, there are two main alternatives that are ideal replacements to EPS: biopolymers and fibre-based solutions. The key point to remember when reviewing these options is whether they are biodegradable or compostable.
Breaking down biopolymers
A polymer is a substance or material built with large molecules that repeat in a chain-like formation. This repetitive structure makes polymers strong and durable. Biopolymers are polymers that are biological in nature, built from naturally occurring molecules, not synthetic ones like petrochemical based plastics. Because they are biological in nature, they’re non toxic and can (as the theory goes) degrade naturally without environmental harm.
Biopolymers are popular as they can be used to create materials that offer a similar performance to plastics. One of the most common bioplastics is Polylactic acid or PLA. This bioplastic is often made from fermented plant starch like corn or sugarcane. Because PLA is plant based, it immediately dodges the embodied emissions that petroleum derived plastics attract. So that’s a big tick.
But the problem with PLA is that it is neither recyclable or entirely biodegradable. As it can’t be recycled, the only choices for PLA made products is to be composted or sent to landfill.
That’s where the trouble begins.
PLA requires high temperatures and special digestive microbes to break down. These are not found in your home compost bin and so need to go to a commercial composting facility. There are only two facilities available in New Zealand (both in the North Island) and there’s no easy way for the average person to drop off their used PLA products.
So most PLA from household waste is ending up in our landfills. That environment is not ideal for PLA to biodegrade and so takes much longer and may not ever fully degrade completely.
Moving on with moulded fibre.
One of the more well known forms of fibre-based packaging is moulded pulp packaging.
Made from renewable resources like trees and plants, using either fresh fibre or recycled products like cardboard and paper, moulded pulp packaging has been around for over 100 years. The first forms were used to pack and ship round products like apples and lightbulbs. Today, one of the more common uses you’ll find at home are egg cartons.
Ironically, moulded pulp packaging was superseded by the plastic fantastic craze in the 1970s, but it's now making a strong comeback in the face of sustainability challenges in the packaging industry.
With improved technology, you’ll now find these renewable packaging solutions are being used for more than just food - electronics and other consumer goods can be presented in smooth, strong yet finely moulded packaging.
In most cases, moulded pulp packaging can be composted at home (as long as it's not been chemically treated) but ideally is put through the existing recycling system to be used again and again.
Moulded pulp packaging is a top solution as an alternative to EPS for its thermal insulation properties and ability to be moulded to form. It is however a heavier final product than EPS.
Where pulp packaging loses its environmental credits is if chemical additives are used in the pulping process or when synthetic resins are added to improve strength and performance. These are significant drawbacks in terms of biodegradability as they continue to introduce synthetic substances into the natural environment when they finally reach their end of life.
Combining the old with the new.
Building on the positives of traditional moulded pulp packaging is a new alternative - bio-composite mushroom packaging.
In recent years, mycelium (the root-like structure of mushrooms) has proven its capabilities as a material with a wide range of uses, from building materials to clothing, and even healthcare products. The fastest growing use is mushroom packaging as it has shown it can oust expanded polystyrene completely.
The beauty of mycelium is that it combines its inherent qualities (water repellency, strength, flame retardancy and lightness) with that of fibres like hemp hurd or wood chip (renewable, sustainable, carbon positive) to create a packaging solution that is a head on competitor to EPS.
Rather than using pulped fibres which require preprocessing to break down fibres into a pliable material, finely macerated wood chip or hemp hurd (the woody innards of the hemp plant) are inoculated with fungal spores that grow on to become mycelium.
The mycelium consists of strong yet lightweight strands that weave their way through the substrate, binding it together into a final moulded form. The result is a light, velvety and completely home compostable packaging product that is circular, sustainable and places little pressure on Earth’s natural cycles.
Growing on the next generation of fibre based packaging with mushrooms
In a time where there’s urgency to replace plastic packaging with renewable, sustainable options, bio-composite mushroom packaging is a truly exciting evolution.
The technology builds on the positives that fibre based packaging provides to create solutions that aren’t just substitutes for EPS but are superior and will shape not just the packaging but a number of industries in the coming years.