Biodegradable plastic is the material that will decompose naturally when introduced in the environment. This outcome is achievable because the microorganisms in the environment are able to break down the structures which make the biodegradable plastic. It creates a result which is believed to be eco-friendly compared to the traditional plastics that we throw away every day.
We can make biodegradable plastics from bio-plastics, which are products that are made from renewable raw materials instead of virgin items that we must harvest at a potential cost to the overall environment. There are typically two forms that we use today: solid and injection-molded. We would use the solid forms for bags, water bottles, and food containers. The other option makes the other plastic items that we consume.
Numerous plant materials are useful in the making of biodegradable plastics today. Manufacturers can create items using plants, starches, corn oil, or even the peels from citrus fruits. That means we no longer need to use the chemical fillers that are found in the traditional items, which then enter the environment when the plastic is melted to release them. Biodegradable plastics offer a substance that is made from a natural source, so the risks of breaking down are much fewer.
These are the current advantages and disadvantages of biodegradable plastics to review.
List of the Advantages of Biodegradable Plastics
1. Biodegradable plastics offer reduces carbon dioxide levels.
We are producing more waste plastic today than ever before in human history. These items are finding their way into our oceans and even contaminating our drinking water. Scientists estimate that there could be more waste plastic in the ocean than fish by the year 2050, with tap water containing microplastics up to 80% of the time. Researchers at the University of Bath have created a plastic that only uses sugar and carbon dioxide, resulting in polycarbonates that no longer need to use petrochemicals and their CO2 emissions necessary for refinement. Plastics like these break down naturally, only depositing the amount of gas back into the environment that was used to create it in the first place.
2. Biodegradable plastics can reduce greenhouse gas emission levels.
When you use biodegradable plastics instead of items made through the traditional refinement process, then fewer greenhouse gas emissions escape into the atmosphere. We consume over 100 million tons of plastic each year, which means the standard 5:1 ratio of production indicates that this industry produces 500 million tons of carbon dioxide that goes into our atmosphere each year. That number is equivalent to the annual emissions of 19 million vehicles.
If we were to recycle our plastics each year, then our net carbon savings alone would be up to 30%, which some researchers suggesting the savings could be as high as 80%. Switching to biodegradable plastics would help to reduce the number of greenhouse gas emissions produced by the industry even further, despite the initial financial costs that would be required to make the transition.
3. Biodegradable plastics are broken down by naturally-occurring bacteria.
After plastics are formed, the traditional products will hold their carbon. When you dispose of them and they begin to decompose in some way, then that gas is released into the atmosphere. Because biodegradable plastics do not always require CO2 as part of the manufacturing process, then this greenhouse gas release may never occur during the decomposition process. When they begin to break down in the environment, bacteria in the soil begin to consume the components. That leaves us with less waste to manage over all, reducing the potential for pollution in every biome.
4. Biodegradable plastics do not release other dangerous items upon decomposition.
If you were to throw out a bucket-full of traditional plastics into a landfill, then you would have methane and other forms of pollutants release as the product begins to decompose. Because these items do not typically exist with biodegradable items, we would be able to take advantage of this supplemental benefit immediately.
Plastics make our lives easier in many ways, but they can also contain potentially dangerous products that could harm our health at the same time. Bisphenol A (BPA) is a key ingredient in resin and plastic manufacturing. In the past, this substance was used in plastic tableware, water bottles, and sports equipment. Phthalates soften the plastic to turn it into PVC. Both are considered to be endocrine disruptors that are toxic to the reproduction cycle of humans. Biodegradables eliminate these substances from being needed.
5. Biodegradable plastics consume less energy during the manufacturing cycle.
Although biodegradable plastics offer a slightly higher cost in the production cycle, we actually consume less energy to produce them. We no longer need to go through the processes of finding, accessing, and transporting hydrocarbons to create plastic items using this technology. That means we are burning fewer fossil fuels, consuming less of them during the manufacturing process, and releasing fewer contaminants when the plastics reach their end-of-life stage. Because of this energy savings, the long-term cost of using biodegradables could be substantially less than traditional plastics – especially if the cleanup costs from plastic pollution are added to that calculation.
6. Biodegradable plastics reduce the amount of waste we produce.
Plastics make up approximately 13% of our current waste stream. That figure represents about 32 million tons of waste each year, with only 9% of that amount directed into recycling programs. The remainder goes into landfills and other waste disposal programs, where it could take up space for more than a century. When facilities have the correct composting equipment available to manage biodegradable plastics, we can experience an entire breakdown of the product in 18-36 months, depending on what method is used.
Even if a complete breakdown does not occur, we would achieve a reduction in the amount of space needed to dispose of the materials. That would create fewer pressures on the overall waste stream.
7. Biodegradable plastics would direct petroleum consumption to other needs.
Traditional plastic products come from the heating and treatment of oil molecules. This process turns them into polymers that become useful for the industry. Roughly 3% of petroleum consumption in the United States is due to the number of plastics that we consume each year. Biodegradables come from products like switchgrass or corn, which means we could redirect the petroleum being used by the industry to our transportation or heating needs instead.
8. Biodegradable plastics can mix with traditional products.
We do not need to make completely new products using biodegradable plastics to create an environmental benefit with this technology. Once the natural materials are turned into polymers, they can work with the ones that were manufactured using oil molecules. That means we can mix the traditional manufacturing cycle with the natural one, reducing the percentage that comes from fossil fuels. When we create this mixture, the plastic products often have more strength as well.
9. Biodegradable plastics require less energy during the manufacturing cycle.
Corn-based plastics represent approximately 40% of the biodegradable source materials that are used for these products in the United States. When you compare the polymers made from this crop to those using raw petroleum, it requires 65% less energy to create a similar-quality biodegradable product. That is in addition to the 68% reduction in greenhouse gases that occur during the manufacturing process.
10. Biodegradable plastics could create new export industries.
In 2016, China produced approximately 290,000 tons of biodegradable plastics. They consumed about 130,000 tons domestically, and then exported the remainder during that year. The growth rate in local sales was 13% from the year before, with the entire value of this segment worth over $350 million. Many of the mature markets for plastic products in the developed world are looking for ways to reduce their carbon and waste footprints. Switching to this product makes a lot of sense because it could eliminate the impact of pollution on the environment over time. Making biodegradables a top priority could become a moneymaking tool for the country that can perfect this technology first.
11. Biodegradable plastics create a new marketing platform.
Although it would be ignorant to say that biodegradable plastics are 100% safe, they are usually viewed as a product that supports sustainable business practices by consumers and those in the C-Suite. Organizations that adopt this product are often seen as being preferable because they are viewed as being concerned about the environment. That means shareholders, executives, and employees all stand to gain from the potential for higher profits. The Coca-Cola Company has already created a bio-plastic bottle that they can use with their beverages. Poland Spring is reducing the number of plastic components that they use for their packaging needs. Making this switch could lead to significant changes in how people and other businesses see each other.
12. Biodegradable plastics can decompose quickly in specific situations.
Bioplastics are generally compostable, which means they will decay into natural materials that will eventually blend harmlessly into the soil. Some of these biodegradable items can break down in a measurement timed in weeks instead of months or years. When the cornstarch molecules encounter water, then they slowly absorb it, swelling up to break the item into smaller pieces. Then the natural bacteria in the composting container digest it to produce something that can benefit the planet later on. You must pay attention to the quality and labeling of the bioplastic items upon purchase to ensure that you are using items that can decompose rapidly.
List of the Disadvantages of Biodegradable Plastics
1. Biodegradable plastics must follow a specific disposal procedure.
We can definitely benefit from the presence of biodegradable plastics because they can decompose effectively in our environment without creating a pollutive effect. This advantage can only occur if the items are disposed of properly, meaning that these items must be treated in a manner that is similar to compost. If we throw out these plastics in the landfill last we would the traditional items, then they will follow a path that is similar to the non-biodegradable option. That is why we must be mindful of recycling programs and waste-reduction initiatives to ensure that we can all take advantage of the benefits that the natural products offer.
2. Biodegradable plastics may contain small pieces of metal.
Although the plastics in the items we use might be biodegradable when we use these technologies, some items (especially plastic bags) might release metals during the decomposition process. The polyethylene created through the manufacturing cycle using natural items may contain high levels of manganese, which can stop breaking down when you begin the composting process for these items.
The Guardian also reported in 2009 that one brand of biodegradable plastic contained high levels of lead and cobalt, which raised questions about the potential toxicity of what gets left behind after the decomposition process.
3. Biodegradable plastics require the weather to cooperate with their disposal.
A study commissioned by the Biodegradable Products Institute in the 2000s found that the breakdown of these natural materials found in biodegradable plastic are exceptionally dependent on the weather conditions in the area. Temperature and humidity play significant roles in the process. Composting goes much slower when the weather turns colder. During times of high humidity, the process almost comes to a complete stop. That means many of the advantages that are possible with this product disappear in equatorial and far-northern climates.
4. Biodegradable plastics do not account for herbicides and pesticides.
We might be using natural products to create biodegradable plastics, but that doesn’t mean we are eliminating our exposure to chemicals through this manufacturing process. Herbicides and pesticides are not tracked by this industry, so there is no way to know what your exposure levels might be when you encounter these natural products. Even organic crops that are sent to the plastics industry can be sprayed with natural compounds that may offer health risks during times of high exposure. Unless we can eliminate chemicals from the entire manufacturing chain, there will always be a risk of pollution to consider with biodegradables.
5. Biodegradable plastics may reduce the amount of recycling that we can do.
When we reduce the amount of traditional plastics that we use by mixing biodegradable molecules in with the oil-based ones, then it does create less of a dependence on petroleum. It also creates a unique disadvantage in the fact that our current technologies do not allow us to recycle these hybrid items once they reach their end-of-life cycle. They must be thrown into our landfills or other waste management systems. That means we are simply trading one issue for another until there is a better solution to find.
6. Biodegradable plastics come at a higher capital cost.
At our current technology levels, it costs up to 50% more to manufacture biodegradable plastics than it does to follow the traditional production cycle. These prices are coming down as our technologies improve and source material access becomes cheaper to produce. Assuming demand continues to increase while production volumes rise at a lower manufacturing cost, the eventual consumer prices for this option should be similar to most of the conventional plastics that we use today. That means it may not be an affordable solution for everyone right now, but it could be in the future.
7. Biodegradable plastics require use to use croplands to produce items.
Our current technologies require us to take over the use of croplands for the production of natural materials to create biodegradable plastics instead of using them to produce food. With scarcity issues and hunger affecting about 1 in 5 families in the developed world and significantly more in developing nations, there is an ethics question to consider when attempting to expand this industry. Is it justifiable to grow cash crops for manufacturing purposes at a time when people need food to eat?
We must also use water resources to crow the crops needed for the raw materials as well. Because corn products represent 40% of the U.S.-based bioplastics industry, so it is notable that one acre requires 3,000 gallons of water for each bushel of yield. Our current technologies can produce 1 metric ton of PLA from 100 bushels of corn. The typical farmer produces 168 bushels per acre.
8. Biodegradable plastics will not solve ocean pollution problems.
Bioplastics cannot decompose in ocean water because it is too cold of an environment for the material. Because it doesn’t break down like it would during compositing, it will either float on the surface like a conventional product or create micro-plastics that are harmful to marine life. Switching to this product is not a magic solution that will resolve our pollution problems. We must address the causes of why we pollute in the first place to ensure our biomes remain healthy for future generations.
9. Biodegradable plastics do not guarantee a net savings.
Many of the advantages of bioplastics rely on a net savings being created by a reducing of energy, water, or greenhouse gas emissions. Because there is no general oversight on the manufacturing cycle from crop growth to final distribution, there isn’t reliable data available to suggest that biodegradables are useful beyond the ability to offer more profits to some companies or create compost fodder. Since many of the reports cited in research involves industry-produced data, we must have access to more independent studies to understand if the advantages and disadvantages of biodegradable plastics are moving in the right direction.
10. Biodegradable plastics may produce methane in landfills.
Our primary concern with greenhouse gas emissions is with carbon dioxide, but we must also consider the amount of methane that we release each year. The reflecting effect of this gas is significantly higher than what CO2 causes. Because some biodegradable plastics produce methane when decomposing in landfills, it is possible that some of these natural plastic items could be creating a more harmful effect on the environment than if we stuck to the traditional manufacturing cycle.
A Final Thought on the Advantages and Disadvantages of Biodegradable Plastics
Biodegradable plastics are often considered a “savior product.” If we can transition to this item, then the potential for waste reduction, micro-plastic contamination, and even ocean acidity can all see significant benefits. There is also the potential to create more pollution. Does it really matter to you if there are biodegradable micro-plastics in your tap water instead of traditional plastics?
The goal should be to reduce overall plastic consumption. Switching to biodegradables is a step in the right direction, but it is not the final solution that we require.
The advantages and disadvantages of biodegradable plastics give us hope for the future because there is an opportunity to reduce our reliance on fossil fuels. It would be inaccurate to say that these items are free from emissions since it requires petroleum to grow crops in the first place. We must also create the infrastructure necessary to process or decompose the biodegradables in a beneficial way. By 2050, we could create a system that is emissions neutral if we make this technology a priority.
Natalie Regoli is a child of God, devoted wife, and mother of two boys. She has a Master's Degree in Law from The University of Texas. Natalie has been published in several national journals and has been practicing law for 18 years.