Biodegradable plastics are very rarely recyclable, and biodegradable does not mean compostable—so they often up in the landfill. Compostable and bioplastic goods can be a better choice than biodegradable ones, but often still end up in landfills unless you can compost appropriately. Conventional plastics are made from products derived from petroleum.
The US Department of Energy reports that plastics are mostly produced from from natural gas processing, and feedstocks derived from refining crude oil—these are the ingredients that last forever in our environment.
They take hundreds of years to break down and never completely decompose—they just become smaller and smaller pieces that are impossible to remove from the environment. Some plastics are known to be toxic, and as they break down, plastic bits become food for organisms up and down the food chain. Biodegradable plastics are made from the same materials as conventional petroleum based plastics, but with even more chemicals.
These extra chemicals cause the plastic to break down more rapidly when exposed to air and light. By fragmenting, rather than degrading, they break into small pieces which can pollute soils, increase risk of ingestion for animals and end up in our oceans and waterways. It breaks into smaller and smaller pieces of plastic. This means they are supposed to break down into biological elements, unlike conventional plastics.
However, while some bioplastics can be composted and do not harm the quality of compost, others leave toxic residues or plastic fragments behind, making them unsuitable if your compost is being used to grow food. Additionally, the use of plant material for bioplastics causes concern including the use of genetically modified crops, and the use of farmland that could be used to grow valuable food crops, deforestation, use of fresh water supplies, soil erosion, fertilizer use which comes from petrochemical sources , food security and more.
Bioplastics cannot be recycled with standard plastics as the additives in bioplastics can make the recycled product less durable. Composting bioplastics is also complicated. Most bioplastics will only compost in commercial municipal composters. Commercial composters reach temperatures and humidity levels you would be unable to achieve in a standard garden composter, so your bioplastics may never break down at home. Some commercial composters, like those in Northern California, have to remove bioplastics like compostable utensils because even their temperatures and humidity levels will not break down these products.
So, is sending these items to landfill the best way to dispose of them? During the degradation process, methane and water are the byproducts of anaerobic degradation, while carbon dioxide and water are the byproducts of aerobic degradation. The end products are humus. The biodegradation process depends on where the plastic is deposited. When it is exposed to more oxygen, for example in an active landfill or compost pile, the films are more quickly degradable.
The amount of methane gas emitted at a landfill is a gauge to rate how active the landfill is and how quickly items degrade. Methane gas is a good indicator of degradation. The more methane gas present, the more active the landfill. Therefore, Maverick biodegradable plastic degrades faster under aerobic conditions and in active landfills. The film will turn into humus and then into either carbon dioxide and water if biodegrading aerobically or with oxygen or methane and water if biodegrading anaerobically or without oxygen.
Most landfills are airless, so methane will be the final product. BMW has a plant in South Carolina which has a pipeline coming from the closest landfill to the plant where it is converted into energy to run the plant.
Johnson and Johnson has done the same. California has just passed a law stating all methane in landfills must be harvested! This is the cheapest source of energy now available. At Michigan State University , scientists are trying to cut production costs for bioplastic through the use of cyanobacteria, also known as blue-green algae, that use sunlight to produce chemical compounds through photosynthesis.
Instead of feeding their plastic-producing bacteria sugars from corn or sugarcane, these scientists tweaked cyanos to constantly excrete the sugar that they naturally produce. The plastic-producing bacteria then consume the sugar produced by the cyanos, which are reusable. Cyanobacteria can be used to feed the microbes that create bioplastic. Stanford University researchers and California-based startup Mango Materials are transforming methane gas from wastewater treatment plants or landfills into bioplastic.
The methane is fed to plastic-producing bacteria that transform it into PHA, which the company sells to plastic producers. It is used for plastic caps, shampoo bottles or biopolyester fibers that can be combined with natural materials for clothing. The bioplastic will biodegrade back into methane, and if it reaches the ocean, can be digested naturally by marine microorganisms.
The Centre for Sustainable Technologies at the University of Bath in England is making polycarbonate from sugars and carbon dioxide for use in bottles, lenses and coatings for phones and DVDs.
Traditional polycarbonate plastic is made using BPA banned from use in baby bottles and the toxic chemical phosgene. The Bath researchers have found a cheaper and safer way to do it by adding carbon dioxide to the sugars at room temperature. Soil bacteria can break the bioplastic down into carbon dioxide and sugar.
Ecovative packaging made of mycelium aims to replace plastic altogether. Photo: mycobond. And then there are those developing innovative ways to replace plastic altogether. Japanese design company AMAM is producing packaging materials made from the agar in red marine algae. The U. Department of Agriculture is developing a biodegradable and edible film from the milk protein casein to wrap food in; it is times better at keeping food fresh than traditional plastic film. And New York-based Ecovative is using mycelium, the vegetative branching part of a fungus, to make Mushroom Materials, for biodegradable packaging material, tiles, planters and more.
But as researchers around the world work to develop greener varieties and more efficient production processes, bioplastics do hold promise to help lessen plastic pollution and reduce our carbon footprint. There is a considerable amount of debate on this issue, for sure. Of course, this would mean a massive alteration in current technology and procedure — something that translates into an immediate rise in expenditure until things level off.
Something the manufacturers of traditional-based plastics will fight against in order to halt immediate losses of profit. So I am asking: who funded this analysis and report? Where did the principle funding for this report originate? It is paid for by the Earth Institute at Columbia University. On my beach, in my water, and in a landfill are Not complete disposal.
Very good article. Here in the Netherlands plastics is a major social issue so companies are looking for alternatives. There is a company here called Vibers which is able to make plastic from elephant grass. Brilliant and stops us using so much plastic! Bio-plastics are a better solution because they will eventually biodegrade and they use much less fossil fuels. Thank you, Shelby Hack. Advanced search A-Z Glossary. Error Cookies are not enabled.
You must enable cookies before you can log in. Login Name. Forgot your password? You are here: Publications Biodegradable and compostable Briefing Biodegradable and compostable plastics — challenges and opportunities PDF. This website has limited functionality with javascript off. Please make sure javascript is enabled in your browser. Topics: Resource efficiency and waste. However, plastics made from bio-based materials are not necessarily compostable or biodegradable. Moreover, plastics that do biodegrade can be made from fossil fuel-based materials.
What is the difference between compostable and biodegradable? What happens to biodegradable and compostable plastics when they are littered? Can citizens compost such products in their own gardens? Can such plastics be recycled? This briefing aims to answer these questions. Key messages If and how quickly a plastic item biodegrades depends on: 1 if it is designed for biodegradation or composting and 2 the conditions it is exposed to after use and for how long.
The conditions in home composters and in the open environment are very different compared to industrial composting plants and this affects the rate and extent of breakdown. Biodegradable, compostable and bio-based plastics need clearer labelling and repeated awareness-raising campaigns targeting users to ensure their correct disposal and treatment.
In a circular economy, all plastics should be recycled into new plastics in the first instance. Compostable plastics that can be treated with bio-waste offer environmental benefits for specific applications and situations, provided their use is aligned with the bio-waste treatment infrastructure. What are the challenges? Biodegradable, compostable, bio-based — what does it all mean?
Box 1. Overview of types of plastic Biodegradable plastics are designed to biodegrade in a specific medium water, soil, compost under certain conditions and in varying periods of time. Anaerobic digestion treats bio-waste without the presence of oxygen.
It generates a digestate and biogas, which is a renewable energy source. References Blesin, J. Identifiers Briefing no. The withdrawal of the United Kingdom from the European Union did not affect the production of this briefing. Data reported by the United Kingdom are included in all analyses and assessments contained herein, unless otherwise indicated.
Related content Sort by: Publishing date Title. Related news and articles Article How green are the new biodegradable, compostable and bio-based plastic products now coming into use? We know that plastic pollution and plastic waste are a big environmental problem. In recent years, new plastic products have been introduced on the market, claiming to be better for the environment.
To find out more, we sat down with Almut Reichel, a sustainable resource use and waste expert at the EEA. But how environmentally-friendly are they?
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