Paper and cardboard are widely used materials in packaging, shipping, and food service, but their environmental impact depends on their type, disposal method, and decomposition conditions. In this blog, we’ll explore how long these materials take to decompose and provide actionable tips for sustainable disposal.
What Types of Paper and Cardboard?
Different types of paper and cardboard vary in composition and biodegradability:
1. Plain Paper
Uncoated and untreated paper, such as office paper or newspapers, decomposes quickly in natural environments.
2. Corrugated Cardboard
Made of multiple layers for strength, commonly used in shipping boxes, it decomposes slower than plain paper.
3. Wax-Coated Cardboard
Used in food packaging to resist moisture, wax coatings hinder decomposition and require special processing.
4. PE-Lined Paper
Paper with polyethylene coating is water-resistant but difficult to compost or recycle due to mixed materials.
5. Recycled Cardboard
Made from post-consumer waste, it often decomposes faster but may contain additives affecting its breakdown.
How Long Does It Take to Decompose in the Ground?
In natural environments like soil or compost piles, decomposition time depends on material type and conditions such as moisture, aeration, and microbial activity.
| Type | Decomposition Time in the Ground |
|---|---|
| Plain Paper | 2–6 weeks |
| Corrugated Cardboard | 3 months – 1 year |
| Wax-Coated Cardboard | Over a year (depends on wax type) |
| PE-Lined Paper | Several years |
| Recycled Cardboard | 2–6 months |
Plain paper decomposes quickly due to its simple composition, while coatings and additives in other types slow the process.
How Long Does It Take to Decompose in the Landfill?
In landfills, decomposition is significantly slower due to the lack of oxygen and controlled conditions. Materials break down anaerobically, producing methane, a potent greenhouse gas.
| Type | Decomposition Time in the Landfill |
|---|---|
| Plain Paper | Months – 2 years |
| Corrugated Cardboard | 2–5 years |
| Wax-Coated Cardboard | 5+ years |
| PE-Lined Paper | Decades |
| Recycled Cardboard | 1–2 years |
Landfills often compress materials, further limiting airflow and slowing decomposition.
Under Which Conditions Does It Decompose?
Paper and cardboard require specific conditions for optimal decomposition:
1. Moisture
High moisture accelerates microbial activity, aiding faster breakdown.
2. Oxygen
Aerobic environments (e.g., compost piles) promote quicker decomposition compared to anaerobic landfills.
3. Temperature
Warmer temperatures speed up microbial activity.
4. Material Coating
Coatings like wax or PE hinder water and microbial penetration, delaying decomposition.
5. Thickness
Thicker materials, such as corrugated cardboard, take longer to break down compared to thinner paper.
Can Paper and Cardboard Be Recycled?
Most paper and cardboard are recyclable, but certain types pose challenges:
- Recyclable: Plain paper, corrugated cardboard (if clean and dry).
- Non-Recyclable: Wax-coated and PE-lined materials, greasy pizza boxes.
Contamination from food or liquids can render otherwise recyclable paper/cardboard unusable.
How to Dispose of Paper and Cardboard?
Proper disposal helps maximize environmental benefits:
1. Recycling
- Sort clean, dry paper/cardboard into recycling bins.
- Remove contaminants like food residues or plastic tape.
2. Composting
- Shred plain paper or cardboard to accelerate decomposition in compost piles.
- Avoid composting coated or heavily printed materials.
3. Landfilling (Last Resort)
- Only dispose of non-recyclable, non-compostable items in landfills.
Can Paper Food Containers Decompose or Be Recycled?
Paper food containers, such as coffee cups or takeout boxes, vary in recyclability and decomposition:
- Decompose: Uncoated or lightly coated containers may break down in compost piles. Industrial composting may be needed for PLA-lined containers.
- Recycled: PE-lined and wax-coated containers are typically non-recyclable due to mixed materials. Check with local recycling programs for guidelines.
Conclusion
The decomposition time of paper and cardboard varies based on material type and environmental conditions. Recycling and composting remain the best options for minimizing their environmental impact, while coated materials pose challenges. By choosing plain, recyclable, or compostable alternatives, we can reduce waste and contribute to a more sustainable future.
Reference Source:
“How Long Does It Take Garbage to Decompose?” – Richland Center Parks & Recreation Department.
“How Long Does Cardboard Take to Decompose?” – Planet Paper Box Group Inc.
“How Long Does Cardboard Take To Decompose?” – Collect and Recycle.
“How Long Does It Take for Common Materials to Decompose?” – RTS.
“How long it takes everyday items to decompose” – Forge Recycling.
“Are All Boxes Recyclable?” – American Forest and Paper Association.
“Takeout Container (Wax or Plastic-Lined Paperboard)” – Napa Recycling.
“How to increase the recyclability of paper packaging” – Food Packaging Forum.
“Achieving Recyclable Food Packaging” – Oliver Inc.
“Take Out Food Container || Recycling” – City of Fort Collins.
“Are Takeout Containers Recyclable?” – Republic Services.
“Biodegradation” – Wikipedia.
