Is Biodegradable Plastic Really Eco-Friendly? 10 Experimental Data Tells You the Truth

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Update time : 2025-06-13

Is biodegradable plastic an environmental savior or a commercial gimmick?

In recent years, “biodegradable plastics” have been promoted as the perfect solution to white pollution. Supermarket shopping bags, takeaway packaging, and even disposable tableware have been labeled as “biodegradable” and “environmentally friendly”. But is this really the case?

In 2024, the international environmental organization Break Free From Plastic released a report stating that more than 60% of the world's biodegradable plastic products can not be completely decomposed in the natural environment, and some of them are even more harmful than traditional plastics.

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Part I: Laboratory Data Exposing the Truth about Degradable Plastics

1. Experiment 1: Comparison of Decomposition Rates in Natural Environments (latest study in 2024)

- Traditional PE plastic: 500 years without degradation (NOAA data)

- Degradable Plastic (PLA):

- Industrial composting environment (60°C): 90% decomposition in 6 months

- Natural soil (25°C): only 30% degradation in 2 years.

- Marine environment: almost no degradation (Nature journal 2023 study)

2. Experiment 2: Comparison of microplastic production

- Conventional plastics: broken into microplastics (particles under 5mm) under UV light

- Oxo-degradable plastics (with additives):

- Oxo-degradable plastics (with additives): broken into microplastics within 1 year (the EU has banned such plastics from being labeled "degradable")

- Truly compostable plastics (e.g. PBAT+PLA): almost no microplastics under composting conditions

3. Experiment 3: Impact on soil ecology

- PLA plastic residues: inhibition of soil microbial activity (experiment 2023 at the University of Bonn, Germany)

- PBAT plastics: completely decomposed by microorganisms within 90 days in compost, no impact on soil health

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Part 2: 5 Major Misconceptions about Biodegradable Plastics

Myth 1: "Biodegradable" = decompose when thrown into the soil

✅ The Truth:

Industrial composting (high temperature + microorganisms) vs. Home composting (low temperature) vs. Natural environment (extremely difficult to decompose)

Only products with "Home Compostable" certifications (e.g., OK Compost HOME) can be biodegradable at home

Myth 2: "Bio-based" = 100% environmentally friendly

✅ Truth:

Cornstarch plastics (PLA) still require industrial composting and decompose very slowly in the natural environment

Some bio-based plastics are mixed with non-biodegradable ingredients, so the actual environmental friendliness is questionable

Myth #3: Biodegradable plastics can be thrown away at any time

✅ Truth:

In a landfill (oxygen-poor environment), biodegradable plastics can emit methane (a potent greenhouse gas)

Into the oceans, the rate of degradation is virtually nil (Science Magazine 2024) Study)

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Part III: How to recognize truly environmentally friendly plastics?

1. Recognize the international certification mark

Certification mark Meaning Applicable conditions

OK Compost INDUSTRIAL Degradable for industrial composting Professional facilities required

OK Compost HOME Degradable for home composting Compostable at home

BPI certified Complies with U.S. composting standards for industrial composting

TÜV Austria Compostable for the EU Rigorous testing

⚠️ NOTE: If a product is only labeled "degradable" but not certified, it may not comply with the standard! Note: If a product is labeled “biodegradable” but not certified, it probably does not meet the standard!

2. Check ingredient list

Recommended materials:

PBAT+PLA (fully compostable)

PHA (marine degradable, but costly)

Avoid:

Oxo-degradable plastics (with PE+additives) (banned in the EU)

Uncertified PLA (may not decompose naturally)

3. Practical test: home composting experiment

Method:

Cut up plastic samples, bury in composting bin

Maintain humidity at 60% and temperature at 20-30°C for 3 months to see if it decomposes. C

Observe decomposition after 3 months