Bioplastics – recyclable, compostable, biodegradable

What are the alternatives to single-use plastics? What are bioplastics? Are some plastics truly biodegradable? Do you ask yourself these questions? I have done some research to help you there and I am about to respond to all of this in this article!

You may wonder why my website is called “Unwrapping Supply Chain” quite simply I grew an interest in the environmental linked to supply chains from biodiversity loss, packaging optimisation and greenhouse gas emissions. When I started working in a warehouse, I noticed the amount of plastic wraps used and discarded from pallets. Thin plastics are difficult to recycle especially with a label like they are in a warehouse. This wrapping and unwrapping of plastic became the title of this website. Despite this, I not covered my opinion and options for plastic alternatives on the website. Rest assured, this day has come!

What’s wrong with plastics?

I don’t want to say everything but it’s quite a lot. These polymers were created for their sturdiness, malleability, lightness and low cost. According to Plastics Europe, plastic is a “term commonly used to describe a wide range of synthetic or semi-synthetic materials that are used in a huge and growing range of applications. … The raw materials used to produce plastics are natural products such as cellulose, coal, natural gas, salt and, of course, crude oil.”

The low cost has enabled the emergence of single-use items where convenience and low cost takes over reusable items. This has been convenient for medicine and increasing the safety of some processes and interventions. This got me wondering what medicine used for instance for IV drips before plastics – it was reusable rubber that gets cleaned or glass. However, the extent of the use has gone far beyond what is necessary with almost every product being available in plastic… truly anything beyond helping medicine.

To assess the impact of a product thus our plastics on the planet you need to take into consideration the Life Cycle of the product. You assess how it is produced, used and discarded to quantify the impact.

For an easy view of the life cycle, you can consider that plastics starts with a polymer as explained above, it is transported to be manufactured and used one or many times. The product is then discarded, put in landfill, burnt for energy recovery or recycled. It is cheap and produced for a high growth linear model. The cost does not bear the social and environmental cost of the produce.

The durability of plastics means it does not biodegrade into non-toxic elements. Plastic does breakdown or degrade after centuries into tiny plastic or powder elements – microplastics. Calling fossil oil based plastic compostable or biodegradable is plain false. This very property of plastic has caused a widespread plastic and micro-plastic overflow considering that 90% of plastics ever created have not been recycled. If you find it difficult to assess what is greenwashing we have some resources. At the current rate of growth, the plastic industry could be responsible for 20% of the oil consumption.

what is the alternative?

Bioplastics have grown in popularity to replace oil based plastics in their previous uses. Before I explain what they are I will remind you of the basics of zero waste. We always try to avoid products rather than choosing a better alternative, then reusable is always the way to go.

Bioplastics are plastic materials produced from renewable biomass sources, such as vegetable fats and oils, corn starch, straw, woodchips, sawdust, recycled food waste, etc instead of fossil based.

Bioplastics can be compostable, biodegradable or recyclable. Although bio is in the name is due to its manufacturing from bio elements not its biodegradability. Some plastics are a combination of both which doesn’t seem to make sense to me. Coca cola’s ‘PlantBottle™‘ uses less fossil fuels but isn’t biodegradable, with this misleading name, my greenwashing radar is going red.

Recycling bioplastics is an option that is put forward by companies but it cannot be recycled with fossil fuel plastics, instead the bioplastics will be recycled together. Therefore, this method requires differentiating the plastics from the bioplastic and having a good enough recycling system to have separate streams.

Compostable material is certified to breakdown into non-toxic elements. It does so at a predictable rate and may need certain elements such as humidity or temperature. This can be at home or in an industrial compost site with a certain temperature or moisture level. Microorganisms break it down into carbon dioxide, water, inorganic compounds and biomass at the same rate as other organic materials in the compost pile, leaving no toxic residue. It is independently certified to prove its compostable status.

Biodegradability is the capacity for biological degradation of organic materials by living organisms down to the base substances such as water, carbon dioxide, methane, basic elements and biomass. So all compostable plastic is biodegradable but not all biodegradable is compostable. It is fairly misleading in the sense that there is not requirement for not leaving toxic residue during the decomposition process.

Both compostable or biodegradable bioplastics will not biodegrade in a landfill due to the lack of oxygen, light and bacteria. Instead, they may release methane like food scraps do in landfills. You get the difficulty in assessing these bioplastics. They also do not biodegrade in the ocean or forest etc.

“The concept that we could use it, throw it away, and it doesn’t matter where you throw it, and it’s going to safely disappear, that does not exist. Nobody could engineer something like that, not even nature.”

Ramani Narayan, professor at the School of Packaging at Michigan State University

Some biodegradable plastics do not disappear but become too small to be seen (oxo-degradable). To be called biodegradable they should become nutrients. They damage the quality of recycling if mixed with plastics during the recycling process. The European commission banned it as it is not considered a solution to the plastic problem.

Pros :

• They can be made of plants so the growth of the plant will capture CO2
• Breakdown in a couple of weeks or months
• Durable Bioplastics are recyclable like the other plastics and take longer to breakdown
• Do not fund the fossil fuel industry

Cons:

• Competes with food crops: may also be grown instead of crops due to higher revenue generation
• Some bioplastics are not biodegradable and hard to differentiate
• Can lead to “green litter” whereby one believes the item can be littered and will biodegrade (while it doesn’t)
• Releases methane when disposed off in landfill
• Heavy use of fertilisers for growing crops such as sugar cane are high pollutants for our health too

To avoid misleading consumers, companies should quantify any environmental benefits claimed. While there are applications where bio-based plastics may be excellent, such evaluations should be based on life cycle assessments (LCAs) and not on simplistic assumptions or claims that ‘bio’ signifies lower environmental impact. Further improvement in the LCA methodology should be researched.

For instance, in assessing life cycle greenhouse gas (GHG) emissions, Nova Institute (2017) calculated GHG emission reductions of around 27% (relative to fossil fuels) in producing PLA, while Shen et al. (2011) calculated that producing PET bottles from bioplastic emits on average 25% fewer GHGs. Comparing fossil and bio-based PET bottles, Chen et al., (2016) suggested a potential reduction in global warming potential of 21% when using woody biomass relative to fossil fuels.

Many brands or products say they are eco-friendly. To check this is a fair claim ask yourself if they:

• Reduce the utilisation of your product or your waste? (ie you use half of the previously required amount of plastic)
• Reuse your product or waste? (ie the product is used indefinitely) 
• Provide you with a recycled material instead of virgin material? (plastic, cardboard or other)
• Will be recycled when the previous option was not?
• Can be biodegraded or composted?
• Come from renewable sources? (not oil, fossil fuels or gas, it can be sugar cane, wood, bamboo…)

My opinion is to avoid single use items as much as possible. When using biodegradable or compostable items, use it instead of plastic packaging not as well as and look at how to dispose of them. This is either through an industrial compost facility or a home compost. If you do not have access to separate compost facility, this is still a better option for you but not great the lack of appropriate disposal seems that it could balance off the advantages by releasing methane and using more resources than plastic..

The production of the item does take off CO2e through the growth of the crop but also uses resources such as land, water and transport. Additionally, the biggest drawback may be the worry of growing the crop instead of food in lower income countries. The big issue with plastics is the disposal mentality making us go through so much and not recycle it. We need to educate the users that the bioplastics cannot be disposed off in the streets or rivers.

However, I believe the composting options will increase around the world enabling us to make the most out the bioplastics. I would also remind readers that toxins released from plastic are still very unknown in their impact so saying that that plastic is the best option is difficult to sustain. On average, we ingest a plastic card worth of plastic every week.