Plastic pollution is one of the biggest environmental challenges we face today. Traditional plastics can take hundreds of years to break down, clogging landfills and polluting oceans.
Some break down only under specific conditions, while others
leave behind harmful microplastics. In this guide, we’ll explore what biodegradable
plastics actually decompose, how they work, and which ones are truly
sustainable.
What Are Biodegradable Plastics?
Biodegradable plastics are made from natural materials like
cornstarch, sugarcane, or cellulose, which microorganisms can break down into
water, carbon dioxide, and organic matter. Unlike regular plastics (which are
petroleum-based), these alternatives are designed to return to nature
safely.
Types of Biodegradable Plastics
1. PLA (Polylactic Acid) – Made from fermented plant starch
(usually corn). Used in food packaging, cutlery, and 3D printing.
2. PHA (Polyhydroxyalkanoates) – Produced by bacteria
feeding on sugars or lipids. Used in medical implants and packaging.
3. Starch-Based Plastics - Blends of starch and
biodegradable polymers. Often used for bags and disposable tableware.
4. PBAT (Polybutylene Adipate Terephthalate) – A fossil-fuel-based polymer that’s biodegradable, often mixed with PLA.
Do Biodegradable Plastics Actually Decompose?
The term "biodegradable" can be misleading. Some plastics only break down under specific industrial composting conditions (high heat and humidity). Others degrade naturally but leave microplastics behind.
Conditions for Proper Decomposition
✅ Industrial Composting
Facilities – Requires temperatures above 50°C (122°F) and controlled
humidity.
✅ Home Composting – Some
biodegradable plastics (like certain PHA blends) break down in backyard compost
bins.
❌ Landfills – Most biodegradable
plastics won’t decompose here due to a lack of oxygen.
❌ Ocean Water – Only a few
specialized plastics (like PHA) degrade in marine environments.
The Problem with "Oxo-Degradable" Plastics
Some plastics are labelled as "oxo-degradable," meaning they fragment into microplastics when exposed to sunlight and oxygen. However, these tiny plastic particles do not fully decompose and still pollute the environment.
⚠️ Avoid oxo-degradable plastics—they’re
banned in many countries for being misleading.
Examples of Effective Biodegradable Plastics
1. Eco-Friendly Food Packaging – Brands like TIPA make fully
compostable wrappers that decompose in months.
2. Biodegradable Bags – BioBag produces plant-based trash
bags that break down in compost heaps.
3. Edible Cutlery – Companies like Bakeys create spoons from
millet, rice, and wheat, which dissolve in water.
How to Choose Truly Biodegradable Plastics
✔ Look for Certifications
- OK Compost (Industrial)
- OK Compost HOME
- ASTM D6400 (US Standard)
✔ Avoid Greenwashing – If a
product says "biodegradable" but lacks certifications, it might not
decompose properly.
✔ Check the Material – PLA and
PHA are better than oxo-degradable options.
FAQs About Biodegradable Plastics
1. Are biodegradable plastics better than regular plastics?
Yes, if they decompose properly. Look for certified
compostable plastics to ensure they break down safely.
2. Can I throw biodegradable plastic in my home compost?
Only if labelled "home compostable." Most require
industrial composting.
3. Do biodegradable plastics release harmful chemicals?
Most certified biodegradable plastics break down into
harmless compounds, but oxo-degradable plastics leave microplastics.
5. Are biodegradable plastics expensive?
Yes, they cost more than regular plastic, but prices are dropping as demand grows.
Biodegradable plastics offer a promising solution to plastic pollution—if they decompose correctly. By choosing certified compostable options and supporting responsible disposal methods, we can reduce plastic waste and protect the planet.