Why are plastic clamshell containers so hard to recycle?
It’s no secret that a lot of how recycling works (and doesn’t work) is confusing. Case in point: plastic clamshell containers. They’re one of the trickiest materials to recycle, and they’re ubiquitous, making them hard to avoid. They’re such an especially frustrating and interesting type of packaging because they’re made of a material that’s easy to recycle in theory but remarkably hard to recycle in practice. Why is this, and what can we all do about it? The answer is super eye-opening, so let’s start with the basics.
What are plastic clamshells, anyway?
Plastic clamshells are hiding in plain sight. It’s likely you have some in your fridge right now. They’re the container of choice for food products like spinach, strawberries, and cherry tomatoes.
Why are they everywhere?
Plastic clamshells are a go-to material for the grocery industry thanks to their lightweight yet durable nature: strong enough to protect fragile items like berries, salad greens, cherry tomatoes, and eggs from damage in transit.
What are they made of?
Most clamshells are made of a plastic called Polyethylene-terephthalate, or PET for short. This plastic has a #1 symbol on it, which is usually one of the few plastic numbers accepted curbside. Clamshells, however, are an exception to this rule. With few exceptions, a surprisingly large number of curbside recycling services do not want your plastic clamshell containers.
Why don’t they want them? What makes them hard to recycle?
There are two main reasons why so many curbside services struggle to recycle clamshells, both having to do with the nature of the materials used to make them.
While most households think of recycling as an activity to reduce waste, for the companies doing the recycling, it’s about creating a new industrial material. While both clamshells and drink bottles are #1 PET plastic, they’re made in distinct ways that give their materials different densities. Plastic clamshells also break into different sized chips than plastic bottles, melt at a different temperature, and often have strong adhesives on them that are hard to get off. All of this means that a recycler can’t just mix clamshells and plastic bottles together all willy-nilly: blending them together can produce a material that doesn’t make for a high-quality recycled container or product.
This means that it’s more desirable for a recycling facility to handle mostly #1 PET bottles or even only #1 PET bottles, since it’s a uniform type of plastic and will result in a relatively pure end product once recycled. Even facilities that accept clamshells prefer bottles, and tolerate only a small amount of clamshells mixed in to avoid spoiling the end product.
Here’s how Octavio Victal, President of Green Impact Plastics put it:
Simply put, not all PET plastic is created equal. Recyclers need bottles and clamshells separated to recycle them properly. Also, most recyclers are set up to recycle bottles, not clamshells. So when they get bales of plastic that also have clamshells in there, it makes things much more complicated and makes the end result lower quality. For many recyclers then, clamshells are basically viewed as garbage that they'd rather not pay for receiving, since they know they'll either have to pick it out or compromise their quality standards.
2. Clamshells aren’t just less desirable plastics. They’re also inherently difficult to sort once they’re in the recycling facility. Since clamshells are so light, once flattened they behave like paper on the sorting conveyor belt, making them hard to separate from other materials. Even facilities with fancy sorting machinery and lots of employees have trouble telling clamshells apart from other types of plastic at the volume they receive them and the speed at which they have to sort them. This makes it easier to simply not accept them in the first place.
How did Ridwell start picking them up?
We started picking up plastic clamshells in 2021 after so many of our Portland members requested it. We knew how tricky they were to recycle, but after we expanded to Portland, Ridwell members made it clear that we needed to help them recycle this ubiquitous plastic. So we began to look for a company in the US that met our high sustainability standards who we could trust to responsibly recycle our members’ clamshells. We eventually found and partnered with Green Impact Plastics, and the rest is history. So far, our members have been able to keep over 112,000 pounds of clamshells out of landfills- that’s more than the weight of a gray whale!
For now, while we continue to look for partners able to support the necessary volumes, we only accept clear plastic clamshells in Portland and select areas of Seattle and South Puget Sound.
What does Ridwell do with clear plastic clamshells?
We work with a game-changing partner called Green Impact Plastics, who turns them into new clamshells.
How can I get Ridwell to pick up my plastic clamshells?
If you’re a member in Portland or certain parts of Seattle or South Puget Sound, you’re in luck. Just head to your member dashboard and opt into an upcoming pickup and indicate that you’d like us to pick up your plastic clamshells. Please be sure your clamshells are clean and clear plastic, since this is the only type of material that our partner can truly recycle.
If you’re a member outside of these two areas without access to plastic clamshell recycling, talk to your neighbors who are members and let us know if you want us to pick up your clamshells. Having lots of interest in an area makes it easier for us to add a new category like this.
If you’re not a Ridwell member, what are you waiting for? It’s an empowering and seamless way to handle your hard-to-recycle materials like plastic clamshells, and loads of other things like plastic film, clothing, batteries, light bulbs, and new featured categories every month. Join us today!