Last week, we talked about take-back programs – what they are and how they work.
However, one is tempted to assume that just because they “recycle” waste, they must be more sustainable.
Today, we’ll try to find out whether that’s actually true. To be frank, we might break a few hearts along the way…
But before we dive into any calculations, let’s go over some basics.
Today's Lesson: Discussing take-back programs
When they make sense and what they keep secret
Number Of The Day
While numbers vary, we can guess that worldwide, about 15–30% of all plastic waste is incinerated (i.e., burned), 61–76% is landfilled, and only 9% is recycled. Of course, these numbers do not differentiate between downcycling and true recycling. Recycling rates are growing slightly, along with the approximately 8% annual growth rate of plastic production over the past 70 years.
9%
Discussing Take-back Programs
The basic idea of take-back programs is that we save the resources and emissions of creating new plastic products through recycling.
This graph comes from Wiah et al. These are some of the most recent numbers I could find.
However, we face two main issues in terms of their sustainability: the impact of recycling itself, and a lack of basic information…
The Black Box Problem
In essence, we cannot generalize the sustainability of take-back programs.
It’s true that the savings depend heavily on the exact item, the recycling setup, and the distance from lab to recycler.
These are recycling facilities in the middle of Toronto - according to google. While it is true that many recycling facilities do not even want to disclose how they recycle to "protect" their processes, most take-back providers do not even disclose which recycling partners they cooperate with. Making it hard to estimate impacts.
But more importantly, we lack data.
Not a single take-back program shares concrete information about recycling plants, processes, or lifecycle footprints. That means we don’t know what happens to the materials we give back - probably it is downcycled.
Most likely, they’re shredded and turned into pellets, but due to missing data, it’s unclear what these pellets are made into.
Recycling means turning waste into the same product or one of equal quality. Most plastics are actually downcycled — meaning they’re turned into lower-quality products like textiles, plastic lumber, or construction materials. For example, they can be mixed into concrete or asphalt. This keeps plastic out of landfills for a while — but it's not circular. The plastic can't be recovered later and is eventually lost.
Although two programs by Starlab and Polycarbin reportedly reproduce tip racks, it’s important to note that plastic cannot be recycled forever. With every cycle, quality decreases. Chemical recycling options that could truly achieve a closed-loop system are not yet widely established — and often come with a bigger footprint.
An Even Darker Mystery?
Sadly, we also need to talk about fraud.
Given the lack of transparency, it's a real concern. From overselling take-back programs to recycling only a fraction of what's collected — many lawsuits never make it into the public eye.
Furthermore, companies with supposed “closed-loop” processes have won awards without openly documenting their methods. Others get certified by third parties with questionable histories…
One example: Bureau Veritas — a major sustainability verifier that has itself faced multiple lawsuits and allegations that are hard to dismiss.
Of course, there are ways to build legitimate down- and recycling systems — but we need to stay vigilant. Too many have misused the system.
How Sustainable Can Take-Back Programs Be?
Every sustainability enthusiast wants take-back programs to make sense.
But to truly assess their sustainability, we would need to know:
The distance between the research facility and the recycling plant
The type and frequency of transport
The item properties (type and amount of waste collected)
The recycling method (mechanism, recycling rates, and how the recycled material is used)
As discussed, not a single company has openly shared a carbon footprint or life cycle analysis. Therefore, I’ve tried to find generalizable numbers (ideally from peer-reviewed sources), but please take them with a grain of salt.
You can find a detailed discussion and an Excel with the calculation of different scenarios made ready for you here.
Below is a summary for:
Whole Plastic LCA
If we consider the full life cycle of plastics — from production to end-of-life — we arrive at 4,000–5,000 g CO₂/kg plastic waste.
Virgin Plastic Production
One key point is the difference in emissions between creating new (virgin) plastic from crude oil or natural gas and recycling the same item. We can estimate 1,500–3,000 g CO₂e/kg of plastic waste for first-generation production.
End-of-Life Impacts
If we landfill plastics: 250–800 g CO₂/kg If we incinerate them: 700–4,500 g CO₂/kg
Energy recovery means converting waste into usable energy (like electricity or heat), often through combustion. Incineration, in contrast, typically refers to burning waste without capturing that energy. Obviously, the more energy can be recovered for other applications, the lower the overall carbon impact — since the avoided emissions from other energy sources are deducted. Some even suggest negative emissions for energy recovery, particularly when using biogenic carbon (e.g., bioplastics, see our earlier post: Biogenic Carbon).
Impact of Mechanical Recycling
Recycling requires energy and chemicals too! We need to sort the plastics, clean them, and melt them into pellets or new products — which means running machines and sometimes applying heat. Sources estimate 100–800 g CO₂e/kg plastic waste. That means, with every recycling round we release emissions! And with current technology, recycling simply delays the inevitable because we cannot recycle forever.
Click to enlarge. As you can see, impacts will mainly depend on A) Amount of given back plastics, B) down- vs recycling and C) transport distance. We chose to determine truck emissions through gCO2e/ton*km. One could also use the consumption of fuel in liters - results will be rather similar.
Truck Emissions
Assuming the lab and the incinerator or recycling facility are similarly distant, truck emissions might balance out. However, if take-back programs require additional trips (because they only collect from specific manufacturers), emissions can add up. Transport vehicles emit ~50–400 g CO₂ per ton per km Vehicle empty weight: 3.5–15 tons Max carrying capacity: ~40 tons
Three Example Calculations
If you assume a 3.5-ton transport vehicle that carries 10 kg of waste that is downcycled:
You end up saving 11 kg of CO₂e if the additional drive is 5 km, but you emit 10 kg extra if it is 20 km.
If we assume true recycling for three cycles, we save 82.5 kg CO₂e for 5 km and break even at around 62.5 km for 10kg of plastic.
Here is an Excel sheet with various scenario calculations for you.
Important Note:
There are important nuances such as that gCO₂e/kg only covers climate change impact — it doesn’t include microplastics, environmental toxicity, or acidification. More on that, including the other 4 nuances (here).
Applying The Knowledge
In the end, we cannot say for certain whether take-back programs are inherently sustainable. It depends on the location and set-up.
Still, if transport routes add a noticeable number of kilometers — for example, because cooperations only include certain recycling plants or because sorting happens at centralized stations — carbon impacts can turn net positive, even though we recycle or downcycle.
Click to enlarge - this graph is from Bauer et al., and as I added, their projection is quire accurate. However, we are at least down from annual growth rates over 8% previously. That means our need for true recycling is as large as ever.
That said, take-back programs are a great way to ensure clean, single-material waste streams. They also incentivize manufacturers to design items from a single plastic, making recycling easier overall.
= Therefore, every lab should ask their service provider for details about the waste transport and treatment process!
If a take-back program breaks even or ends up slightly carbon-positive, I would still advocate for it — because adoption is the only way to push for better, more robust recycling systems.
Take-back programs will always emit emissions. Therefore:
Reduction first, reuse second — and only then, recycle.
Upcoming Lesson:
The Surprising Sustainability of Refill Systems
How We Feel Today
References
All references for the impact numbers can be found here.
Schyns, Z. O. G. et al., Mechanical recycling of packaging plastics: A review. 2020. Macromolecular Rapid Communications, First published: 30 September 2020. doi:10.1002/marc.202000415
Houssini, K. et al., Complexities of the global plastics supply chain revealed in a trade-linked material flow analysis. 2025. Communications Earth & Environment, 6, 257. https://doi.org/10.1038/s43247-025-02169-5
Geyer, R. et al., Production, use, and fate of all plastics ever made. 2017. Science Advances, 3, e1700782. doi:10.1126/sciadv.1700782
Wiah, E. N. et al., Transitional probabilities for plastic waste management and implication on sustainability. 2022. Sustainable Environment, 8(1), September 2022. doi:10.1080/27658511.2022.2118654
Material Economics et al., Industrial Transformation 2050: Pathways to Net-Zero Emissions from EU Heavy Industry. 2019. University of Cambridge Institute for Sustainability Leadership (CISL). https://materialeconomics.com/publications/industrial-transformation-2050
Zheng, J. et al., Strategies to reduce the global carbon footprint of plastics. 2019. Nature Climate Change, 9, 374–378. doi:10.1038/s41558-019-0459-z
Bauer, F. et al., Plastics and climate change—Breaking carbon lock-ins through three mitigation pathways. 2022. One Earth, 5(4), 361–376. doi:10.1016/j.oneear.2022.03.007
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