What Is The Difference Between Biodegradable Plastic And Compostable Plastic?

biodegradable and compostable plastic


With the rising interest in products that provide an alternative to plastic and are more sustainable and environmentally friendly, bioplastics such as biodegradable and compostable have entered the market.

The difference between biodegradable and compostable plastic is that one breaks down in landfill and the other requires disposal in a home composter or industrial composting facility. Both are considered bioplastics, however, compostable plastic can’t breakdown in landfill and biodegradable plastic can’t breakdown in a composter. Biodegradable plastic can leave behind toxic sludge when breaking down, whereas compostable plastic returns to its natural state when disposed of correctly – back into the earth. Oxo-biodegradable plastic is not to be confused with either bioplastic, as it breaks down as microplastics that can be toxic to the soil around it.


What Is Biodegradable Plastic?

Biodegradable plastic is often seen as a great alternative to plastic, as it breaks down faster than traditional plastic, which can take centuries to breakdown in landfill. The way that biodegradable plastic is designed, is to breakdown faster with specially designed microbes in the materials.

This means that a biodegradable plastic bag may breakdown in months rather than its traditional counterpart which can take decades or centuries. Biodegradable plastic is often classed as a bioplastic as it’s ‘bio-based’, however, it still contains some toxic chemicals similar to conventional plastic.

Biodegradable plastic’s organic components consist of materials such as the sugar from corn and sugarcane, which is then converted into polylactic acids. The alternative is to engineer the plastic with microorganisms to breakdown faster.

Biodegradable trash bag 

What Are The Pros And Cons of Biodegradable Plastic?

Biodegradable plastic is definitely seen as a better choice than conventional plastic, having several benefits for consumers and the environment, however, with this also comes some negative impacts. This is due to the presence of toxic chemicals from the traditional plastic materials included in biodegradable plastics.

The benefits of biodegradable plastic include:

  Quicker breakdown period than traditional plastics – breaking down in months rather than decades or years.

  Some ingredients are bio-based and will break back down to their natural state into the environment.

  Can be disposed of in landfill with the rest of your household garbage.


The downfalls of biodegradable plastic include:

  Toxic sludge often left behind from the conventional plastic materials as it breaks down.

  Can’t be broken down in a composter.

  Doesn’t completely breakdown into natural components.

  Can’t be recycled because the recycling plants can’t differentiate between traditional plastics and biodegradable and this will contaminate the batch.


How Does Biodegradable Plastic Break Down?

Traditional plastic will eventually breakdown, however, this can take centuries or even thousands of years. The aim with these plastic alternatives – such as biodegradable plastic – is that this process will be shortened to months or less due to the addition of chemicals of microorganisms to assist breakdown.

Plastic is broken down by microbes or fungi in the environment over time. Biodegradable plastic can take three to six months to decompose completely. Some may be up to a year or more. The timeframe depends on several factors such as moisture or temperature.

When manufacturing biodegradable plastics, extra chemicals or microorganisms are added which will cause the plastic to breakdown more rapidly when exposed to air and light. This means that the environment that these plastics are placed in are key to the time it will take to break them down.

Oxo-biodegradable plastics are designed to degrade when exposed to UV light, however, these are seen a more toxic than biodegradable plastics due to them breaking down into fragments (micro plastics) rather than completely.

Read more about oxo-biodegradable plastics here or further in this article.


What Is Compostable Plastic?

Compostable plastic is seen as the current top choice on the market for environmentally friendly and sustainable plastic alternatives due to its ability to breakdown into natural components when disposed of correctly.

Compostable plastic is made from organic components that can breakdown in a home composter, worm farm or industrial composting facility directly back into the soil. This means that no toxic chemicals are either emitted or left behind during this process.

The materials vary, but include renewable materials such as corn, soy protein, potato, tapioca starches, lactic acid and cellulose. These materials mean that compostable plastics are non-toxic and can decompose when composted.

Compostable plastics are made to return to the environment when they breakdown and also to provide nutrients to that environment. These are made from organic materials and able to be decomposed quickly with a home or industrial composter.

Compostable plastic can’t be disposed of in landfill or it may take as long as traditional plastic to completely breakdown. Learn more about compostable plastics here.

compostable bags for home composting

What Are The Pros And Cons of Compostable Plastic?

Compostable plastic is seen as the top choice over conventional plastic, having several benefits for consumers and the environment. However, there are some minor negatives to consider, such as the inability to dispose of these plastics with your normal household waste.

Benefits of using compostable plastic include:

  When disposed of correctly, compostable plastic can breakdown in as little as 90 days or less.

  Compostable plastic completely breaks down into its natural environment when disposed of correctly.

  The breakdown of these plastics can provide compost and fertilizer for your garden or industrial landscaping.

  Compostable plastic is made from natural materials, meaning that gashouse emissions and use of electricity, water and the like are greatly reduced during manufacturing.

  Can be disposed of in a home composter, a worm farm or an industrial composting facility.

Some cons of compostable plastics include:

  The inability to be disposed of with the rest of your household garbage.

  Any leftover waste inside compostable bags must be removed or it may hinder the composting process (if not able to go into a composter).

  Not as readily available as a complete alternative to traditional plastic – not as many products on the market to completely switch to compostable plastic.


What Are The Two Types of Compostable Plastics?

There are essentially two types of compostable plastic: PLA and CPLA. These are both compostable materials that can be used for some of the same, and some different uses. They are both made from renewable materials and able to be broken down in a home composter, worm farm or industrial composting facility.

What Is PLA?

PLA – or polylactic acid – is made from fermented food starch such as sugarcane, sugar beet pulp, corn or cassava and then combined with lactic acid and cyclic di-ester lactide. It retains the same key properties to traditional plastics.

PLA is almost carbon neutral, doesn’t emit toxic fumes, uses less energy than conventional plastic, doesn’t leave behind toxic chemicals, generates fewer greenhouse gases, provides jobs in rural areas and is safe for humans, pets and the environment.

It’s also certified as safe for food packaging and medical use. PLA doesn’t handle high temperatures well and soften or deform at high temperatures, making it less ideal for food or drink containers that may be left in a hot car.


What Is CPLA?

CPLA – or crystallized PLA – is a heat resistant form of PLA. It’s made from the same materials, however, can withstand higher temperatures. This means that CPLA can be used for coffee cups, soup containers and hot food containers.

CPLA is often white rather than transparent unless charcoal is added to create a black color.


How Does Compostable Plastic Break Down?

Compostable plastic contains organic materials such as tapioca starch, potato or corn starch, soy protein, cellulose (a component of paper) and lactic acid. This makes the bag ripe for decomposing in a natural environment such as a composter or worm farm.

Compostable plastic is made to breakdown to their natural components being made from organic materials. They are able to breakdown rapidly – in 10-90 days in most cases – in a home composter, worm farm or industrial composting facility.

Ideally, compostable plastic is broken down in an industrial composter as that’s what it is designed for rather than landfill. These composters are set up perfectly with the right temperature, moisture levels, air and other important factors for decomposition.


Compostable bags won’t decompose well in landfill and will contribute to the plastics problem. Typically, in the right environment, a compostable bag will average 90 days to decompose in a compost bin. Check out the home experiment we undertook with an Etsus biodegradable trash bag!


What Are Bio Plastics?

Bio plastics are a term used for a suite of plastic alternatives that contain renewable sources and organic materials, making them more sustainable and environmentally friendly than traditional plastic. Biodegradable and compostable plastics are examples of bio plastics.

The idea behind bio plastics is that they contain renewable materials and can assist in reducing the problem of plastic waste and contributions to landfill. Typically, bio plastics should be 100 per cent degradable, versatile, strong and sustainable.

The manufacturing process of bioplastics should reduce carbon footprint, save energy, reduce greenhouse emissions and not contain any harmful chemicals to humans or the planet.


What Are Oxo-Biodegradable Plastics?

Oxo-biodegradable plastics are a type of plastic that is designed to breakdown rapidly into smaller fragments also called micro plastics. Unfortunately, this type of plastic alternative isn’t great long-term for the environment.

Oxo-biodegradable plastic is made from conventional plastics such as polyethylene, polypropylene or polyethylene with metal additives to increase its ability to degrade when exposed to UV light. The plastic will breakdown quickly into fragments, however, will not completely breakdown and leaves smaller microplastics behind in the environment.

You can find out more about oxo-biodegradable plastics in this blog.

oxo-biodegradable plastic

The Confusion About Different Plastics

Although alternative plastics bring a lot of positives for consumers who are conscious of their environmental footprint, a lot of confusion also follows. This can mean that consumers who may assume they are protecting the environment with their choices, may end up contributing to the pollution proper through incorrect choices or disposal.

For example, biodegradable plastics can’t be disposed of in worm farms, home composters or industrial composting facilities as it will not breakdown and will also contaminate the surrounding soil and microorganisms.

Compostable plastics can’t be disposed of anywhere except a home composter, worm farm or industrial composting facility or else they will not breakdown and will contribute to the landfill problem.

Oxo-biodegradable plastics can’t be disposed of in a worm farm, home composter or industrial composting facility or will mean toxic plastic introduced into a composting environment or compostable plastic being placed in landfill where it will take the same time as traditional plastic to breakdown.

The microplastics that result from oxo-biodegradable plastic disposal can lead to toxicity in composting or worm farm environments.


Understanding Your Plastics

It’s important to understand which plastics you have at home and how to best dispose of them. For traditional plastics, some are recyclable and will be marked as such underneath. You can read more about these plastics and their disposal methods in this article.

When it comes to bio plastics, understand which type you have and how to best dispose of it. Consider a worm farm or home composter and you will be rewarded with nutrient-rich soil or fertilizer. Of course, this is for compostable plastics only.

Understand more about the composting process here.

It’s important to understand these key differences:

  Compostable plastics must be disposed of in a home composter, worm farm or industrial composting facility. Never landfill.

  Biodegradable or oxo-biodegradable plastics must be disposed of in landfill. Never a composter.

  Traditional plastic must either be disposed of with your household waste, recycled (if applicable) or avoided.

Follow the rules for how to dispose of your plastics and you could reduce your environment footprint and your contributions to landfill and pollution.


What Are Popular Uses For Biodegradable And Compostable Plastics?

Although not every current traditional plastic item is available in bio plastic alternatives, there are still many biodegradable and compostable plastic products on the market for numerous uses. It’s a global market, with people everywhere considering how to reduce their environmental impact.

Biodegradable Plastic Products

The Most Popular Biodegradable Plastic Products

Biodegradable plastic is currently more popular and available than compostable plastics, mostly due to its cheaper manufacturing process and variety of uses. Biodegradable plastic is used for everything from garbage bags and food packaging to medical supplies and building supplies.

Some common biodegradable plastic items include:

  Food packaging including takeaway containers or bags

  Disposable food serving such as plates, cups or cutlery

  Plant pots

  Garbage bags

  Carry or grocery bags

  Packaging for products such as toiletries

  Tea bags

  Other types of storage containers.

To ensure you’re choosing the best biodegradable plastic products, ensure they contain a certification in the form of a logo on the product or the packaging. This lets you know that the product is certified as biodegradable and not false advertising.


The Most Popular Compostable Plastic Products

Compostable plastics are increasing their product range as they become the ‘go-to’ plastic alternative, however, still don’t have as many products on the global market as biodegradable. This is often due to the lack of manufacturing facilities and the cost to manufacture.

Popular compostable plastic items include:

  Garbage bags

  Carry or grocery bags

  Food packaging such as containers, bags, plastic window in boxes

  Food serving items such as cups, cutlery, plates and napkins


  Sticky tape or packing tape

  Toiletry packaging.


Compostable plastics – PLA and CPLA – can be utilized in medical environments for uses such as medical implants, drug delivery systems and orthopedic devices as they are non-toxic.


Which Is The Most Sustainable And Environmentally Friendly Plastic?

For those looking for an alternative to traditional plastic, both biodegradable and compostable plastics are a great option. However, compostable could be seen as the top choice, due to its ability to not only breakdown into natural components, but also leave behind zero toxicity.

Compostable plastic is a great alternative to other traditional plastics for many reasons such as being made from raw materials, making them sustainable, renewable and compostable. Their manufacturing process uses less energy, produces fewer greenhouse gas emissions and contributes to job growth in rural areas, whereas the same cannot be said for traditional plastic.

Compostable plastic is also non-toxic and versatile, meaning it can be used in applications from food packaging, carry bags and trash bags to cutlery, coffee cups and food service items. It is also certified to break down in an industrial composting facility in under six months.

It’s also safe for home composting and worm farms, producing excellent fertilizer for your garden or large landscaping projects in the case of industrial composting facilities.


What Certifications Are Around For Plastic Alternatives?

Many products may be marketed as biodegradable or compostable, however, it’s important to understand what you’re buying and have assurance that they are as sustainable as you are hoping for. This comes in the form of certification, which is available around the world.

There are five common certifications for biodegradable and compostable plastic:

  Biodegradable Products Institute (USA)

  Australasian Bioplastics Association (Australia)

  American Society for Testing and Materials (USA)

  International Organization for Standardization (Global)

  European Bioplastics (Germany).

You can read more about these companies here.

certifications for compostable plastic

What Does Certification Mean?

What many may not know, is that the bioplastics industry is well-regulated. There are several available certifications, meaning that consumers can get rest assured they are purchasing a certified compostable product.

A certification for compostable plastic essentially means that it is non-toxic and can be broken down in a composting environment. In order to be certified, companies must have their products undergo a testing regime in an approved lab and then that report will be reviewed by the relevant certification group.

The testing is evaluated against the relevant industry standards before formal certification is provided and the product is labelled as biodegradable or compostable. If it passes certification from these key groups, they will supply a certificate and logo that the company can use for that particular product or material.

These logos allow consumers to easily identify a certified compostable product or material, knowing that when disposed of correctly, they will live a circular lifestyle and go back to the environment. At this point in time, many home composting items are under a voluntary verification scheme (for example in Australia under the home composting standard).

Is Certification Compulsory?

Unfortunately, certification for compostable or biodegradable plastics is currently completely voluntary. There are however, current standards across the glob relevant to each country. Companies often choose to become certified in order to gain credibility with their consumers – who are increasingly becoming more and more aware of plastic alternatives.

Consumers can also rest assured that the product is non-toxic to them, their families and the environment when a product is certified compostable. This is a clear advantage for companies as they are then distinguished as selling a bioplastic and not a conventional plastic to consumers and other companies. The certification provides proof of product and also allows simple sorting of waste.

The certification also helps to ensure the correct handling of the product in the composting process. This will help a consumer to not only identify that your product is certified compostable but also that they need to dispose of it in a home composter or industrial composting facility.




Bioplastics such as biodegradable and compostable, are growing in popularity due to their lower environmental footprint and increasing accessibility for consumers. With the inclusion of renewable materials, these plastic alternatives are better for the environment than conventional plastics.

Biodegradable plastic products can be disposed of in landfill and will breakdown in months rather than the decades or centuries it takes traditional plastic to breakdown. However, they can’t be placed in composting facilities or worm farms and may leave behind toxic sludge as they decompose.

Compostable plastic products are 100 per cent sustainable, non-toxic and renewable, breaking down into a completely natural state such as water, carbon dioxide or biomass when disposed of correctly. They can release methane which is a potent greenhouse gas if they are disposed of in landfill and they will not breakdown rapidly.

Oxo-biodegradable plastic is similar to biodegradable plastic, however, it won’t breakdown completely in the landfill environment, and leave behind micro plastics which are toxic to the environment and humans. The manufacturing process for these bioplastics is environmentally friendly and a great alternative to traditional plastic manufacturing due to less energy usage, fewer greenhouse emissions and no toxic fumes.

The versatility of these materials make their applications broad, from food service items, food storage and trash bags to medical applications such as implants, drug delivery systems and orthopedic devices. CPLA can withstand higher heat, making it an ideal alternative to plastics such as polystyrene for coffee cups, soup containers and other hot items.

Overall, compostable plastics are better options than traditional plastic due to their raw materials, less harmful manufacturing processes and ability to be composted and returned to their raw materials. Biodegradable plastics are a close second, being made from partial organic ingredients and able to be broken down rapidly in landfill.




    We’re on the mission to research the best sustainable products and these are what we found, these are the questions that we are asking. Disclaimer, we are not scientist but we are heavy researchers and we are passionate about sustainability.