At Mama Bamboo, we’re committed to making the most sustainable choices—not just in materials, but in real-world impact. That’s why, starting in January, we’re beginning a gradual transition from compostable packaging to fully recyclable packaging across our nappy range. While our compostable bags sounded like the perfect eco-friendly solution, the reality is that the UK simply doesn’t have the industrial composting infrastructure needed to process them properly and not everyone can compost at home.
By moving to widely recyclable packaging, we’re ensuring that every parent can dispose of our products responsibly and easily, helping us achieve a far greater positive environmental impact in practice—not just in theory.
Why 51% rPET Comes Out on Top: A Clear Look at Packaging Sustainability
When it comes to choosing sustainable packaging, the options can feel overwhelming. From compostable to paper to plastics, every material has its own story—and its own environmental footprint. To cut through the noise, we compared five commonly used packaging materials across carbon footprint, recyclability, resource use, and more.
The results? 51% recycled PET (rPET) consistently performs best overall, offering a strong combination of low environmental impact and high circularity.
🌍 51% rPET: The Strongest Sustainability All-Rounder
Across all categories, 51% rPET (a mono-material made with just over half recycled PET) shows the most balanced and robust environmental performance.
Here’s why it stands out:
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Low carbon footprint – substantially lower than virgin plastic and most paper-based options.
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Minimal water and land use – because much of the material is reused, it avoids resource-heavy agriculture and forestry.
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Widely recyclable – fits seamlessly into established PET recycling systems, supporting true closed-loop recycling.
Overall, 51% rPET delivers the lowest total environmental burden and offers excellent material efficiency with strong, lightweight performance.
🔍 How Other Materials Compare
🌽 Corn-Starch PLA
Corn-starch PLA is often marketed as a “green” alternative, but the reality is more complex. While it performs moderately well on carbon footprint, it comes with challenges:
- Limited real-world composting or recycling options—especially in the UK, where industrial composting infrastructure is minimal.
📦 Unlined Paper or Waxed Paper
Paper feels like a natural choice, but its environmental cost is higher than many expect:
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Paper production is energy- and water-intensive, and requires significant land for forestry.
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It tends to be heavier, which means higher transport emissions.
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Consumers often report that unlined paper packaging tears easily or absorbs moisture, increasing the risk of damaged goods.
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If the paper is waxed to provide some durability and moisture resistance, it cannot be recycled:
- ⚠️ Not recyclable — the wax coating contaminates paper recycling streams
- ⚠️ Not compostable (if paraffin-based) — paraffin wax is petroleum-derived and doesn't biodegrade easily
- ⚠️ Moisture/barrier performance — whilst an improvement on unwaxed paper, it is still generally inferior to Recycled-PET
- ⚠️ Land use & water — paper production can have higher land use and water consumption impacts
- ⚠️ Weight penalty — you may need MORE material (by weight) to achieve equivalent strength/barrier
🆕 Virgin PET
Virgin PET benefits from strong recyclability but has a major downside:
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It carries the highest fossil-based carbon footprint, making it far more resource-intensive than recycled PET.
🧻 Paper lined with PET plastic
This composite format consistently performs worst overall.
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It cannot be recycled in either paper or plastic streams.
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It is usually heavier than alternatives, which drives up emissions.
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It combines environmental impacts from both paper and plastic—without offering circularity.
📊 Side-by-Side Comparison
|
Category |
51% rPET (Mono) |
Corn-Starch PLA |
Paper (Unlined) |
Virgin PET |
Paper + 51% rPET Laminate |
|
Recyclability |
✔️ Widely recycled |
⚠️ Limited composting |
✔️ Recyclable (if clean) |
✔️ Widely recycled |
❌ Not recyclable |
|
Carbon Footprint |
✔️ Low (~1.2–1.3 kg CO₂e/kg) |
⚠️ Moderate (1.3–1.5) |
⚠️ Moderate–High |
❌ High (2.1–2.9) |
❌ Very High |
|
Marine Eutrophication |
✔️ Very low |
⚠️ Moderate–High |
⚠️ Moderate |
✔️ Low |
⚠️ Moderate |
|
Material Efficiency |
✔️ Lightweight & strong |
✔️ Good |
❌ Heavy, weaker barriers |
✔️ Good |
❌ Heavy |
|
Resource Use |
✔️ Very low |
⚠️ High land/water |
❌ Very high |
⚠️ Moderate |
❌ Highest |
|
Overall Impact |
⭐ Best |
Mid-range |
Medium–High |
High |
❌ Worst |
⭐ Final Thoughts
If the goal is to reduce environmental impact without compromising strength, functionality, or circularity, 51% rPET is the clear leader.
It offers the strongest combination of low carbon emissions, efficient use of resources, and compatibility with established recycling systems.
In a world where packaging decisions matter more than ever, 51% rPET provides a practical, scalable way to lower environmental footprints today—without waiting for future technologies or infrastructure.
Source Material - Devera
Raw Material Emission Factors
| Material | EF (kg CO2e/kg) | Source |
|---|---|---|
| 51% rPET + 49% virgin PET (blended) | 1.94 | Ecoinvent 3.9.1 |
| PLA (cornstarch-based) | 3.20 | Ecoinvent 3.9.1 |
| 100% Virgin PET (for reference) | 3.19 | Ecoinvent 3.9.1 |
Impact on 0.1 kg product (Raw Materials only)
| Scenario | Raw Material CO2e |
|---|---|
| Current (51% rPET blend) | 0.194 kg CO2e |
| PLA alternative | 0.320 kg CO2e |
| Difference | PLA is ~65% higher |
Key Insights
📊 Surprising result: Cornstarch-based PLA actually has a higher carbon footprint than the 51% recycled PET blend in the raw material phase. In fact, PLA's EF (3.20 kg CO2e/kg) is almost identical to 100% virgin PET (3.19 kg CO2e/kg).
Why is PLA not necessarily "greener"?
- Agricultural inputs: Growing corn requires fertilizers, pesticides, irrigation, and land use — all with associated emissions
- Processing intensity: Converting cornstarch → lactic acid → polylactic acid is energy-intensive (fermentation, polymerization)
- Land use change: Indirect land use impacts can be significant
- Biogenic carbon: While PLA is bio-based, the Ecoinvent EF accounts for the full lifecycle including agricultural and processing emissions
Where PLA does have advantages:
- ✅ Fossil resource depletion — PLA uses renewable feedstock, reducing dependency on petroleum
- ✅ End-of-life — PLA is industrially compostable (though infrastructure is limited)
- ✅ Biogenic carbon — carbon was recently captured from atmosphere (climate neutrality argument, though debated)
Where 51% rPET wins:
- ✅ Lower climate change impact per kg
- ✅ Proven recyclability — PET recycling infrastructure is well-established globally
- ✅ Circular economy — using recycled content reduces virgin material demand
Bottom Line
From a pure carbon footprint perspective, 51% recycled PET product (0.31 kg CO2e total) significantly outperforms what a PLA equivalent would deliver (~0.43 kg CO2e estimated total). The recycled content in PET is the key differentiator — it dramatically reduces the material's footprint below both virgin PET and PLA.
