Does Biodegradable Plastic Help the Environment?

Plastics are, without a doubt, a great convenience. They are lightweight, flexible, moisture resistant, and cheap to produce (and purchase). The popularity of plastic is evident in the amount of plastic waste generated each year: enough to circle the Earth four times. Typical plastic takes an extremely long time to break down (up to 1,000 years), and only a fraction of plastic waste is recycled. Most of it (more than 25 million tons per year) ends up in landfills. Given these facts, it would seem that biodegradable plastics would be one of the great developments of our lifetime. But does biodegradable plastic really help the environment?

Pros of Biodegradable Plastic

Faster Breakdown Period

Biodegradable plastic can break down in just a matter of months, depending on the environmental conditions in the landfill. Even if they do not completely break down, any reduction in landfill mass is an advantage for the environment.

Reduced CO2 emissions

Compared to the refinement process for traditional plastics, creating biodegradable plastics releases fewer greenhouse gasses. And since biodegradable plastics don’t always need CO2 for manufacturing, that gas is not necessarily emitted during breakdown. Interestingly, researchers and the University of Bath have created a plastic from sugar and CO2. It can biodegrade back into these same elements, resulting in a CO2-neutral process.

Elimination of dangerous ingredients

Traditional plastics contain toxic products like Bisphenol A (BPA) and Phthalates (a softening ingredient) that are dangerous to humans and other animals. Biodegradable plastics, such as the those mentioned above, can be created without these harmful components and providing an environmental advantage.

Decreased reliance on petroleum

Almost 3% of petroleum consumption in the United States comes from the creation of plastic. Since biodegradable plastics are created from primarily from crops (corn, for example) they represent a renewable alternative to finite resource. And while the timeline of “peak oil” is still debatable, the fact remains that at some point, we will have to get by without.

Cons of Biodegradable Plastic

Unlikely to break down in the ocean

Much of our plastic waste – biodegradable or not – ends up in the ocean where temperatures are typically too low for the material to decompose. This leave the plastic floating in the water or breaking down into micro-plastics that can then enter the food chain. This is a disadvantage for plastics of any kind, and a notable one at that.

Plastic bottle floats underwater
Photo by Brian Yurasits on Unsplash

Less food production from farm land

As noted above, many biodegradable plastics can be produce with crops. However, this means that crops that could otherwise be contributing to our global food supply are instead contributing to our global plastic supply. With world hunger a very real issue, it is fair to consider the priority use of our farm land.

Reduced CO2 emissions offset by more methane

CO2 emissions are often regarded as the primary culprit among greenhouse gasses, and they do indeed account for the largest percentage of them. However, methane is far more effective at trapping heat in the atmosphere, and biodegradable plastics are more likely to contribute to higher methane levels. In short, this is a trade-off that does not necessarily ease the trend of global warming.

Reduced recycling

Counter-intuitively, the increased presence of biodegradable plastics is a con in that it could actually lead to a decrease in the effectiveness of recycling efforts. Some of these new plastics need to be composted rather than placed in a recycling bin, and composting is a far less prevalent practice. Additionally, the label of “biodegradable” could lead to a false sense of security that just throwing the item away is acceptable because is will simply “break down.”


So, does biodegradable plastic help the environment? While it does indeed offer some notable advantages, there are plenty of cons to consider along with the pros. The points on both sides seem pretty even here. So, while they are not a net negative, it seems that biodegradable plastics do not necessarily help the environment.

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