How many times can plastic be recycled?

Even the most recyclable plastics don’t have eternal life

As more companies try to green up their product offerings, you’ve likely noticed wares on your favorite store’s shelves touting “made of recycled plastic” labels. The eco-conscious consumer might consider goods as wide-ranging as e-readers, cat toys, and plant pots specifically because of the number of plastic bottles recycled to make them. 

But reading that ad copy might make you wonder: How many times can plastic be recycled, anyway? The short answer is there isn’t firm, reliable data to provide a concrete number, but it’s unlikely to be more than a couple of times. 

What are different plastic recycling processes?

Before we can talk about how many times we can recycle a plastic product, we have to define the plastic recycling processes we’re talking about. There are two methods: mechanical recycling and chemical recycling.

Historically, a plastic bottle going into a recycling bin would land at a mechanical recycling plant. Mechanical recycling is the catch-all term for anything physically done to turn used plastic into something new. The methods involved include sanitizing, cleaning, grinding, or remolding. “When we’re talking about mechanical recycling, or physical recycling, you’re ultimately just melting down the material and putting it into other material,” explains Shelie Miller, an environmental sustainability professor at the University of Michigan’s Center for Sustainable Systems.

By contrast, chemical recycling is a relatively newer slate of technologies, namely gasification, pyrolysis, and depolymerisation. Miller says “it’s essentially almost dissolving the plastic back down to its initial molecules and then rebuilding those molecules rather than melting it down into something that is a less-quality product.”

What are different types of plastics and their recycling potential?

There are seven different categories of plastic products. While all of them can theoretically be converted into something else, keep in mind that the recyclability of a plastic ultimately depends on the ability of a given facility to process the product close to where you’re using it or throwing it away.

#1 Plastic

Known as PET or PETE, this material is used to make bottles and jars for standard household goods, like salad dressings, medicine, and water, but also rope and tote bags. This type of plastic can theoretically be converted into a variety of products: clothing and other textiles, containers, sleeping bags, and even boat sails, according to Quality Logo Products, which sells plastic goods.1

#2 Plastic

High-density polyethylene, or HDPE, is also used in a lot of containers for household goods, such as juice, milk,  shampoo, and laundry detergent. Toys and trash bags are both made with HDPE. Recycled HDPE can be turned into plastic crates, lumber, and fencing.

#3 Plastic

PVC plastic, or polyvinyl chloride, is used in everything from cling film and grocery bags to sewage pipes and gutters. Not all recyclers can accept it, but it does have some potential for a second life. Canadian recycling company CleanRiver says PVC can be ground down and turned into a plastic powder or pellets for reuse. With less than 1% recycled every year, Quality Logo Products classifies PVC as “one of the least recycled materials.”

#4 Plastic

Low-density polyethylene is typically used for products like squeezable bottles, toys, packaging, pipes, and insulation, but it also can make up thin plastics like cling wraps, sandwich baggies, and frozen food bags. It can be recycled into garbage bags, trash cans, shipping envelopes, and some furniture, but it has to be separated out from other recyclables.2 Unseparated, it contaminates other recyclables and can damage equipment.

#5 Plastic

Known as polypropylene, #5 plastic is super common in your house, but especially in your kitchen. It can be found in single-use cutlery, plastic plates, take-out containers, yogurt or margarine tubs, and medicine bottles. 

#6 Plastic

Polystyrene, or #6 plastic, is a “transparent, rigid, and brittle” material,” the most well-known form being styrofoam. Used in shipping and as single-use food containers, few facilities accept it for recycling. 

#7 Plastic

This is a broad category of “leftover” plastics that don’t fit in anything else. Fiberglass and nylon are two such #7 plastics, as is polycarbonate, a thermoplastic found nearly everywhere,” according to Xometry, an on-demand industrial parts marketplace. It’s used in eyeglasses, medical devices, automotive parts, and lighting fixtures.

What determines how many times plastic can be recycled?

Several factors determine how many times a given piece of plastic can be recycled. First, the quality of the original plastic influences how much more it can be recycled. If a plastic starts its journey as an insubstantial product like a hot drink lid, it probably can’t be recycled at all. From there, the number of times it can be recycled will also depend on the subsequent products it becomes. For example, a bottle becoming a bottle may mean the quality is still high enough to become yet another bottle. But if that bottle is instead turned into, say, spongy playground turf, its recyclability from that point is limited.

Another factor is the additives imbued into a plastic during the original manufacturing. Certain chemicals, like per- and polyfluoroalkyl substances, or PFAs, may give a plastic a desirable color or function but may make it difficult to responsibly recycle an item.

A bottle becoming a bottle may mean the quality is still high enough to become yet another bottle. But if that bottle is instead turned into, say, spongy playground turf, its recyclability from that point is limited.

The contamination of a plastic also affects its overall recyclability. For example, a perfectly recyclable plastic bottle could show up at a recycling facility covered in styrofoam, which is often difficult to recycle. If that facility doesn’t also handle the foam, it may just throw the entire shipment of potential recyclables in the garbage. That’s because it’s inefficient to clean off and decontaminate the possibly useful plastic.

The number of times something can be reborn also depends on where a product is used—or moved. If a product is continuously used and recycled in areas that have strong plastic collection and remanufacturing programs, that will extend the usability of the underlying plastic. But if it’s used somewhere that has no recycling at all, the plastic is destined for the dump or the environment, even if the product itself perhaps is easy to reconstitute.

Then there’s the environmental impact of recycling a product, even if it’s technically feasible. The amount of power or other inputs—like water or more virgin plastic—needed to recycle a product may mean it’s illogical to recycle it.

So how many times can plastic be recycled?

While some articles might cite specific numbers as to how many times plastic can be recycled, experts say the number of factors involved in determining a plastic product’s recyclability means it’s not so easy to land on a broadly applicable and accurate number. “I don’t think I’ve seen great research on what exactly that number is and how that changes if you remove some of these harmful additives or other things like that,” says Anja Brandon, the Associate Director of U.S. Plastics Policy for the Ocean Conservancy. “I think it’s really hard for folks to know what that number is given how many other complicating factors there are in the plastics to begin with.”

Are there environmental benefits to recycling plastic multiple times?

Every time a plastic product is successfully recycled, it reduces—but doesn’t eliminate—the need to use virgin plastic. The less virgin plastic is needed, fewer raw materials and resources (i.e., fossil fuels) are required to produce it. That would mean less natural gas and oil production and greenhouse gas emissions. In 2019, for example, plastics generated 1.8 billion metric tons of greenhouse gas emissions, with 90% of those coming from their production and conversion from fossil fuels,” according to the Organisation for Economic Co-operation and Development (OECD).3

Additionally, less new plastic should also mean less waste and pollution, which should theoretically reduce the stress on our ecosystems and our landfills.

What happens if we don’t recycle plastic?

When plastic isn’t recycled, it’s destined for the landfill, an incineration power plant, or the environment. And most of it isn’t recycled. The U.S. Environmental Protection Agency reports that the plastic recycling rate was just 8.7% in 2018, although #1 and #2 plastic products saw higher recycling rates of 29.1% and 29.3% that year, respecitvely.4 That overall plastic recycling rate fell to around 5% in 2021, according to a Greenpeace study.5

What is plastic downcycling?

Plastic downcycling occurs when a plastic product is recycled into an item with poorer quality or less structure than it originally had. That might look like a plastic PET bottle being turned into textiles, like carpeting or clothing, instead of another bottle. That new product will only continue to degrade in further uses.

While experts say that plastic downcycling isn’t ideal recycling, Brandon, of the Ocean Conservancy, says that doing so is still helpful. “It’s delaying landfilling and that’s good—it’s still displacing the need for virgin plastic,” she says. “But you’re not getting to that circular goal that we are all working for.” 

Does recycling plastic promote the circular economy?

Plastic recycling is only one piece of a circular economy. A truly circular economy would be one in which we only produce and use products and materials that can be reused, regenerated, repaired, or recycled. Currently, the EPA estimates that the U.S. throws out enough trash every day to equal around 5 pounds per person—meaning we have a long way to go to achieve a circular economy.

“I’m not against plastic; I’m against making stupid products out of plastic. When you make a lot of single-use things—like bottles and bags and straws and couplers and all kinds of film packaging—there really isn’t a viable recycling plan without heavy subsidies.”

Marcus Eriksen, co-founder, 5Gyres

And according to the Ellen Macarthur Foundation, a charity dedicated to creating a circular economy, “while improving recycling is crucial, we cannot recycle our way out of the plastic issues we currently face.” Instead, the foundation recommends three strategies to create a circular plastics economy: eliminating the plastics we don’t need; use the plastics we do need in reusable, recyclable, or compostable compositions; and circulate plastics we create to keep them out of the environment or incinerator.

Although the general public does need to reduce its overall consumption of unnecessary plastic products, the average consumer can’t take unilateral action to drive the necessary, foundational steps toward a circular economy. To that end, the foundation explains that government officials “are essential” to develop regulations and infrastructure needed for plastics collection, while manufacturers need to responsibly design their products or packaging to optimize recyclability.

The future of plastic recycling

Marcus Eriksen, a researcher and co-founder of plastic pollution organization 5Gyres, sees an obvious first step for the future of plastic recycling. “I’m not against plastic; I’m against making stupid products out of plastic,” he says. “When you make a lot of single-use things—like bottles and bags and straws and couplers and all kinds of film packaging—there really isn’t a viable recycling plan without heavy subsidies.”

To that end, Eriksen wants to see more legislation passed focused on expanding the responsibility of companies that use and make plastics beyond the point of sale. Six U.S. states have laws on the books known as EPRs, or extended producer responsibility policies which essentially require commercial and industrial entities to reduce plastic in their products and increase the recyclability of the goods that do utilize the material.

Given that much plastic is shipped long distances to its potential recycling point, Eriksen also wants to see more recycling infrastructure developed in a “hub and spoke” model. That would help decentralize the process away from major, faraway centers into smaller hubs with regional outposts to expand the availability of recycling to more plastic users.

  1. Types of plastic and their recycle codes, Quality Logo Products, Jun. 2019. ↩︎
  2. LDPE plastic recycling process, EDL, May 2021. ↩︎
  3. Global plastics outlook, Organisation for Economic Co-operation and Development, Jun. 2022. ↩︎
  4. Advancing sustainable materials management: Facts and figures report, United States Environmental Protection Agency, 2020. ↩︎
  5. Circular claims fall flat again, Greenpeace, 2022. ↩︎