Biodegradable vs. Compostable Plastic Bags: The Real Difference

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Plastic bags are everywhere you go. As you drive down the road, bags are blowing around or sitting in a ditch. There are so many that it genuinely makes you wonder what impact they’re having on the environment. However, with the implementation of biodegradable and compostable bags, we can lessen the impacts we are having on the earth.

Both biodegradable and compostable bags are similar in that they break down into natural materials that do not harm the earth. However, compostable bags break down to provide nutrients and a soil conditioner. Biodegradable bags simply break down without toxifying the earth.

In our modern world, we use plastic bags nearly every day. Whether it be for carrying groceries, for a trash bag, or when cleaning our homes, it’s critical to find a more environmentally friendly alternative. In this article, we will discuss the differences between biodegradable and compostable plastic bags and how they can benefit the planet.

The Break Down

Before we get into the differences between biodegradable and compostable plastic bags, it’s critical to understand what plastic really is, and why it is so harmful to human, animal, and environmental health. Synthetic plastics are plaguing our planet, and because of this, alternatives have been skillfully created.

Plastic bags consist of several different materials from polyethylene (the most used plastic) to ethylene (a hydrocarbon that is colorless and flammable) and are then infused with additives and color. Blending occurs typically at the heated stage, and then the sheets are blown into their designated shapes. The plastic is then cooled and pressed.

While there are many other steps to this process, it is essential to know that the “ingredients” used to make the traditional plastic bags are not natural or healthy in any way. Polyethylene and ethylene are both unhealthy for human interaction and for the planet, and therefore, from the start of their production, plastic bags are problematic.

Knowing how plastic breaks down is important in finding alternatives. It is not wise to add to the environment’s problems with more waste; thus, by changing the types of bags we use, we can make big differences in our world. Since polyethylene and ethylene plastic bags do not break down for 10-20 years, utilizing alternatives could provide relief to the planet.

In addition to taking decades to break down, plastic bags break down into tiny pieces of toxins through photodegradation with the help of UV rays from the sun. This combination of ethylene and radiation breaks down the plastic causing it to become brittle. Unfortunately, this process can take up to fifty years for plastic to completely break down, at which point it disperses into microplastic.

Microplastics infiltrate our water and food systems and are a major cause of death not only for animals all over the globe but upwards of one million people annually. For these reasons, it is critical we start using alternatives that can break down.

Biodegradable Plastic

Biodegradable means that a material can break down entirely and return to nature. Biodegradable is also called “bio-waste,” where items can decay without harming the environment. Bags can be made biodegradable using organic ingredients rather than manmade materials. They may consist of cornstarch and vegetable oil instead of lab-made chemicals.

To be disposed of properly, they typically need direct sunlight and help from microorganisms in order to break down and incorporate into the earth fully. When put into the right conditions, the bag breaks down into its natural plant-derived state, resulting in no environmental harm.

Compostable Plastic

Compostable means that an item can return fully to a natural state. However, it also means that bag should also be able to provide the earth with nutrients as compost. Compost serves as a ground conditioner that helps plants and ecosystems thrive. Therefore, compostable bags, typically made of plant starch, do exactly that while also reducing the need for fertilizers.

Once broken down, compostable bags turn into a nutrient-dense soil that can be used in gardens or to help plants grow. Basically, by using compostable bags, the plant-based ingredients used go full circle to wind up right back in the earth! In utilizing compostable bags, more crops can be grown, and the soil can become more nutrient-rich to encourage more species to utilize the soil.

By creating more nutrients in the soil, not only will more insects reside in the soil and work to keep it healthy, but more animals will be able to feed off of the land. Compost can be majorly beneficial to human and animal health simply by providing more care to the environment.

Benefits to Alternative Plastics

By switching to a more environmentally friendly plastic, we are working to decrease the number of animals dying around the world from plastic pollution. Not only are animals ingesting microplastics, but they also commonly get stuck in plastic waste, which can inhibit their ability to eat, swim, breathe, or walk.

This issue is lessened with the implementation of biodegradable or compostable bags; because although the two are different, they are both solutions to decrease the amount of plastic that is taking lives every single day.

Soil and Water

Plastic bags break down into toxins that turn around and contaminate and damage the soil that grows our plants. These toxins can leak into our waterways (on top of what is already there). What we have is a cycle of toxicity where we take in the toxins that already exist in our water and soil and add more to it day by day by throwing away plastic waste improperly.


With toxins and pollution in our waterways, it poses a danger to our sewage. Wastewater goes out, originally meant to compost back into the ground, except now it is filled with toxins, and unable to compost. On top of that, these pieces form together and cause blockage and can cause a backup. Many times, we have flooding in the streets near our homes due to these blockages.

This situation also becomes a breeding ground for bacteria that can cause disease and illnesses. Unfortunately, this issue is not fully resolved by using compostable bags as those require the optimal environment in order to fully breakdown. A compostable bag that is not properly composted is just as bad as an ethylene plastic bag.


Plastic bags have become a large part of the pollution problem with the effects that it has on animals, earth, and even humans. Pollution is the entire picture at once. Unfortunately, plastic bags make one of the most significant portions of pollution, right alongside plastic bottles and other manufactured items. Pollution has increased dramatically in the last fifty years and has caused significant damage to the planet.

The use of biodegradable plastic bags can majorly improve this issue due to the decreased microplastic pollution. If we use alternative plastics, we can prevent future contamination, crop infection, and ocean pollution. We instead contribute to a healthier future for our planet.

How to Get Rid of Plastic Bags

If you have to use one of these plastic bags, be aware of how to dispose of the bags properly. Avoid just letting them sit outside or throwing them in the trash can. It’s important to be more conscious of what steps we are taking to really clean up the planet. If you can reuse the bags, reuse them. However, if you cannot reuse them, here are some ways to dispose of them.

Proper Disposal
With proper disposal and recycling of all of our waste, we can make a big change in our earth and our carbon footprint. Many times, we lack the ability to take the time or the energy to make sure that our waste is taken care of in a productive and clean measure. In order to dispose of your materials correctly, it is critical to be clear on exactly what they are made of.

If any of these materials are not disposed of correctly, they will instead end up in our waterways and soil just like any other synthetic materials that take decades to break down. Therefore, regardless of which option you choose to utilize, take note of how they should be disposed of to reduce waste.


Many stores have recycling bins for plastic bags.  You can collect your bags and put them into the collection bins inside of your store. Also, be sure to check with your local recycling center as some cannot take your items since plastic bags can cause significant damage to machines.

However, there are some that do take in plastic bags as long as they are labeled #2 or #7. Any plastic bags that you are using will be labeled as to if they are synthetic plastics, compostable, or biodegradable so that you know exactly if they are able to be recycled or not.

Waste Management

In many places, there are “dumpsites” or recycling sites with many bins for the type of waste. Be sure to follow guidelines regarding your waste and make sure it is a clean waste. Make sure to put your bags in the correct bin as some areas have different types of plastic bins.

If we recycle plastic bags, we can reduce the energy and waste produced when manufacturing plastic bags.


Composting materials requires a designated location to create the compost. This can either be a bin in the home or a pile outside. Regardless of how you decide to set up your compost, the most important thing is that it has the system is set up properly so that the items placed inside will actually break down.

Creating compost requires that you first lay some straw or twigs directly on the ground. If you have a bin to collect your compost inside the house, be sure to take it out and put it outside in this spot in the ground whenever it gets full. Next, you’ll need to add your compost materials in addition to manure or any nitrogen source to aid in the breakdown process.

This could be anything from wheatgrass, grass clippings, buckwheat, or clover. Once you have your compost materials and a nitrogen source in the pile, you’ll want to ensure your compost stays moist. If you do not check the moisture and keep it damp, the materials will not be able to break down efficiently.

If you are using compostable bags, it is critical that you include them in your compost pile along with any other materials you choose to compost. However, if you are using synthetic plastic bags, they will not break down and work within your compost system, and therefore, it is important to only put compostable materials into the pile.

Resource Intensity

Another difference between biodegradable and compostable bags worth noting is the resource intensity needed to produce the bags. Production of bags can put a dent in resources, not only from the materials used to make them but also the production materials needed.

This production process not only includes the oil needed to extract the raw material, but also the resources put into manufacturing, loading, and transporting the plastic bags to where they need to be. This process uses a lot of energy, and with bags that can be composted or broken down easily, natural resources are in higher demand.

By continuing to create plastics out of oil, it will require more drilling for oil and more planting of environmentally harsh oils such as palm oil. Therefore, while these bags do not present the pollution and chemical risks, they do have their own flaws when you factor in all the resources used to produce them.

Carbon Footprint

The carbon emissions accrued in making bags differs depending on the materials required. Making bags out of compostable plastics uses the least amount of carbon dioxide and produces the least amount of greenhouse gas emissions. In producing degradable plastics, more carbon dioxide and water are required.

This process returns carbon back into the atmosphere, which speeds up the process of climate change. This continues warming the ocean and causing climate alterations such as global warming. While stray synthetic plastics cause ocean warming due to the chemicals and heat released as the sun reflects off of them, biodegradable bags are still going to be superior.

Even though they do have a higher potential for carbon emissions, they do not pose nearly as many risks to animal and human health and life. Therefore, compostable and biodegradable bags are a better option, as long as they are disposed of correctly.  However, they are not the best option.

Cutting Out Plastic

The absolute best option when it comes to cutting back waste, reducing carbon emissions, and minimizing chemical use is to use reusable bags. While they do take additional materials and carbon emissions to create, they are used more throughout their lifespans, and therefore the carbon footprint ends up being less over time.

Whereas with plastic bags, the carbon footprint is smaller at first, but is barely used more than twice, and therefore the greenhouse gas emissions add up more quickly. However, if reusable bags are not an option for you, consider how you can continue giving back to the planet with the resources you do have.

If all you can do is use compostable bags, be sure you are actually composting them. If you are using biodegradable bags, give them the right environment to biodegrade so that they do not pollute the world and become a potential threat to wildlife. In cutting out synthetic plastic, we all have a role to play, and there are many avenues to explore in order to accomplish a common goal.


Utilizing biodegradable and compostable plastics is a major step forward in protecting the environment and minimizing the continued signs of climate change. It is critical that when you are using these types of bags that you are clear on exactly how to care for the bag so that it can break down properly.

Using more environmentally friendly bags is ideal when those who are implementing them into their lives know exactly how they need to be cared for in order to have a lesser impact on the environment. If these bags are treated like synthetic plastic bags and thrown directly into the trash, they will have a similar fate to synthetic plastic bags.

In addition, this is extremely unfortunate because, with their higher carbon footprint, their main redeeming quality is the fact that under the right circumstances, they can be broken down more readily and with less environmental harm. Therefore, if you are going to use these types of alternatives, commit to following through on their disposal processes.

This may mean that you start a compost bin either in your home or outside in your yard where you can put your plastic bags in addition to your food waste to break down and provide nutrition to the soil around you moving forward. If these are not processes you are able to follow through with, it may be the best option to use reusable bags instead!

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