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0 Compostable plastic is plastic that biodegrades into water, biomass, and gases under compostable conditions within three to six months.
As people are becoming more and more aware of the environmental impact of plastic they are shifting towards alternatives. An excellent replacement for single-use plastics, specifically trash bags, is compostable plastic.
It biodegrades, requires less energy for production, emits fewer GHGs, and is made from renewable sources.
Studies have shown that if the US switches completely to compostable plastic made from bio-based materials by using renewable energy, the greenhouse gases (GHGs) associated with the plastic industry will go down to zero.
Let’s have a look at this game-changing plastic alternative in detail!
What is Compostable Plastic?
Compostable plastic is a type of plastic that biodegrades completely within three to six months into water, biomass, and gases, such as methane and carbon dioxide under controlled environmental conditions.
Compostable plastic is made from renewable and bio-based materials such as corn, potato, tapioca starch, cellulose, soy protein, and lactic acid. It could sometimes be made from petroleum.
The main environmental factors affecting compostable plastics compostability include:
- Temperature
- Moisture content
- pH
- Oxygen level
- Microorganisms population
Comparison Between Traditional and Compostable Plastic
| Traditional Plastic | Compostable Plastic |
| Traditional plastic is made from petrochemicals, one of the biggest sources of air pollution. | Compostable plastic is generally made from plants, so minimal emissions are involved. |
| The manufacturing process is energy-intensive and polluting. | It requires less energy and releases fewer GHGs. |
| It takes somewhere between decades to centuries for traditional plastics to disintegrate. | This type of plastic generally decomposes in commercial composting facilities within three to six months. |
| Some traditional plastic types, specifically polyethylene, release methane and ethylene, two major GHGs, when disintegrating under sun exposure. | Compostable plastic also produces methane, sometimes even higher than traditional plastic, when not handled properly. Composting facilities implement ways that reduce methane production, and some of them even use it to produce biogas, an alternative renewable energy source. You can do the same at home as well! |
| Traditional plastic doesn’t deteriorate quickly. | Compostable plastic deteriorates quickly at temperatures above 43°C (110°F). |
Is Compostable Plastic Good for the Environment?
Yes, compostable plastic is good for the environment because it produces fewer greenhouse gases (GHGs) throughout its lifetime. In addition to this, it decomposes, whereas, traditional plastic doesn’t and keeps polluting the soil, oceans, and air.
Research suggests that if the US completely shifts to compostable plastic, it will cut down GHGs by 25%, which would be equivalent to 6 million tonnes of CO2e/year (mean value).
Another solution is to shift polymer manufacturing to renewable sources. It will result in an overall GHGs reduction of 50%–75%, around 38 million tonnes of CO2e/year. Unfortunately, going this way won’t be helpful as even though GHG reduction will go down, the biodegradability issue will persist.
The study concluded that the best way to cut down emissions and solve the biodegradability issue is to produce biobased plastic through renewable energy sources. The emissions might even go down to approximately 0 CO2e/year or negative.
Why Switch to Compostable Plastic?
The world should switch to compostable plastic from traditional plastic because it releases less GHGs, doesn’t pollute the oceans, is good for human health and well-being, and deteriorates within months, so there’s less waste.
Green House Gases (GHGs) Emissions
In 2019, traditional plastics were expected to be responsible for more than 850 million tons of CO2 equivalent. The studies were underestimating, this number ended up around 1.8 billion tonnes of GHGs, which is approximately 3.4% of the global emissions.
The biggest reason behind this massive number is the production and conversion process from fossil fuels; the percentage stands at 90%.
The story doesn’t end here. The airborne microplastics contribute to global warming by reaching remote regions, such as the Arctic, absorbing light, and decreasing snow’s surface albedo.
Ocean Pollution
Each year, we dump eight million metric tons or 176 billion pounds of plastic into the oceans.
You can learn more ocean pollution facts from our post on ‘18 Pollution Facts About the Ocean‘.
The top five plastic polluters in the ocean are:
- Cigarette butts
- Food wrappers
- Plastic bottles
- Bottle caps
- Plastic grocery bags
All of these are single-use plastic, which means they are used for mere minutes before they are released into the environment to wreak havoc for centuries to come.
The best alternative is to make them with compostable plastic. An excellent example in this regard is compostable garbage bags. Given that, at once we are using multiple trash bags in a single home, switching them with compostable ones significantly reduces plastic waste and emissions. Head over to our post on ‘7 Best Biodegradable Garbage Bags of 2022 (Contains Compostable Options)‘ to get yours now!
Human Health and Well-Being
Two of the main human health and well-being impacts of traditional plastics on humans are:
- They release microplastics that enter our food streams and water, which may have long-term health impacts. They were found in human blood and in the placentas of unborn babies.
- Traditional plastics contribute immensely to GHG emissions, a major threat to human health. Only the transportation involved in bringing the raw materials to the plastic factories release 12.5 to 13.5 million metric tons of greenhouse gases. Every year, 7 million people die prematurely due to air pollution.
Compostable plastic solves both these issues, as it releases fewer GHGs in comparison with conventional plastics. Also, since they biodegrade and are generally made from bio-based material, we don’t have to worry about microplastics.
Less Landfill Waste
Currently, we are producing twice the amount of plastic that we did two decades ago. Most of it either ends in landfills, gets incinerated, or pollutes the oceans.
Many of you might be thinking, what about recycling?
Even though almost everyone is preaching about recycling, only 9% of the overall plastic waste is recycled.
Landfilling is the most common plastic waste disposal method in the majority of countries. With the increasing plastic pollution, it’s becoming difficult to landfill it due to lack of space.
In addition to this, all the waste muddled up together releases toxins that leach into the ground, and contaminate groundwater and the soil.
What are the Standards, Logos, and Labels of Compostable Plastic?
There are various standards around the world that govern the production, usage, and composting of compostable plastics. They are separate for home and industrial compostable plastic because industrial ones don’t compost under the conditions present in home composters.
In addition to this, all the European standards are for compostability in soil. Currently, there isn’t a standard for compostability in water, but International Organization for Standardization is working on developing it for marine environments.
While purchasing an item made out of compostable plastic, make sure that you check the logo or the certifying standard. Also, ensure you pick the right one as per your composting capabilities. If you plan on composting at home, then don’t go for industrial ones.
On the flip side, if your council picks up compostable trash, then go for industrially compostable plastic as they have the required facilities and conditions.
We’ve listed the main standards, logos, and labels of compostable plastic from Europe, North America, Australia, and New Zealand in the table below.
We hope, by now, you would have learned quite a bit about compostable plastics. If you want to learn more about how plastic impacts our environment, and how you can stop using it, head over to our post on ‘Plastic Pollution | 12 Ways on How to Stop Using Plastic‘. Every small effort helps, so keep switching your lifestyle bit by bit into a sustainable one to help reverse the climate crisis!
FAQs
What are compostable plastics?
Compostable plastics are plastics that biodegrade under controlled composting conditions into water, biome, and gases. They are generally made from plants, such as soybeans, potatoes, and corn.
What are compostable plastics made of?
Compostable plastics are made from bio-based materials or petroleum. The plant-based materials generally used are corn, potato, tapioca starch, cellulose, soy protein, and lactic acid.
Is compostable plastic biodegradable?
Yes, compostable plastic is biodegradable. The industrial one biodegrades under industrial composting conditions, whereas, the home ones decompose in home composters, so make sure you read the label before getting it.
How long does it take for compostable plastic to decompose?
In industrial composting conditions, compostable plastic decomposes within three to six months. In home composters, it usually takes 90 days if the conditions are correct. If not, then it might take longer.
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