Are Bioplastics The Solution To Our Plastic Crisis?

Why we need bioplastics

The current state of plastics threatens our ways of life in more ways than one, from the dependence on fossil fuels to the rising issue of plastic pollution and microplastics that have the potential to affect DNA.

Recycling plastic is fraught with deceptive and ineffective practices, and more often than not our plastic waste gets shipped overseas to other countries or buried: out of sight, out of mind!

And when plastic is shipped across the ocean, it still largely ends up back there anyways via the pipeline of plastic-filled rivers in places like the Philippines, as many nations don’t have the infrastructure to handle huge amounts of plastic waste.

The plastic problem is one that’s tempting to ignore – as plastic is one of the most cost-effective and useful products ever created – but the mounting danger of the waste it creates, both in how it’s manufactured and disposed of after use, is becoming impossible to turn away from.

In a report published by The Pew Charitable Trusts, an expert panel suggested that:

• The annual flow of plastic into ocean garbage patches is set to almost triple by 2040, to 29 million metric tons per year
• This is the equivalent of 110 lbs (50 kg) of plastic for every meter of coastline worldwide
• Governments are often too narrowly focused in on the wrong countries when it comes to plastic waste
• Solving the ocean plastic crisis will require multiple solutions
• Solutions both downstream and upstream need to be used
• Industries and governments have the solutions to reduce ocean plastic by
  about 80% by 2040, while delivering on other societal, economic,
  and environmental objectives

In addition to the issue of plastic waste, there’s also the growing concern of various chemicals slowly leaching out of abandoned plastic trash sitting in landfills and floating around in bodies of water (like endocrine disruptors).

So, are bioplastics part of the answer? Many people think so.

But the shift toward more sustainable production methods often does little but accelerate the amount of waste produced, and degradable plastics aren’t always what they seem.

To understand these issues, let’s take a look at the current state of bioplastics and what the future holds for plastic technology.

What are bioplastics?

There’s a lot of money going into researching exciting new ways to generate plastic. As it currently stands, bioplastic is currently separated into three major categories:

• Bioplastics made from renewable sources, sometimes designed to be biodegradable, including common forms like PLA and PHA
• Petroleum-based bioplastics that are sourced from fossil fuels but made into biodegradable forms
• Combination plastics, using monomers from a mix of biological and petroleum sources

It’s possible that plastic can be biobased – that is, sourced from a biological origin – and not even designed to be biodegradable!

In this case, a bioplastic may be just as bad for the environment as a petroleum one, or worse. Then, there are different levels of degradability, and this is where a lot of the confusion lies.

Biodegradable plastics make up all plastics, technically. Given enough time, plastic will break down into smaller pieces – but this is where much of our problems with plastic pollution occur.

It takes plastics a very, very long time to break down, and when they do, the products are harmful.

To biodegrade simply means to be broken down on a microbial level, and this process occurs at varying rates and under different conditions unless it’s being done within strictly controlled environments.

So, there is plenty of room to call something biodegradable, even if its breakdown has only been demonstrated in a lab and the conditions of the landfill don’t fit the requirements.

One step further would be compostable bioplastics. These would biodegrade in your typical garden or landfill environments, and do so in a reasonable timeframe – potentially even reintroducing useful nutrients to the soil.

While these can breakdown in backyard composting setups, we’ve included bioplastics on our list of what not to compost. These materials simply take too long to breakdown at home, realistically.

And no, you’re not alone in feeling confused!

The main issues with bioplastics

Firstly, there’s more than one problem with plastic production.

Bioplastics usually aim to tackle either the issue of plastic waste or plastic production, and the solutions to these problems are often at odds with one another.

Which means that switching to biodegradable or compostable plastic will do nothing to curb emissions if those plastics use the same fossil fuel resources and are just as resource-intensive to produce (or worse).

Similarly, using renewable sources to form plastics may help reduce dependence on fossil fuels, but could ultimately increase other forms of pollution – especially if these sources require destructive farming practices or the resulting plastics end up contaminating recycling batches.

But perhaps more importantly, there’s a very loose definition of what constitutes bioplastic, and this will inevitably need to be regulated better to prevent companies from paying lip service with their (technically) biodegradable plastic products.

A majority of bioplastics aren’t designed to be biodegradable, even including those which are “biobased”.

And biobased plastics still need space devoted to farming the materials used during production. While many can be made from crop residues unfit for human consumption, this isn’t always the optimal source – and replacing petroleum plastics with biobased ones will take land, water, and fossil fuels, ironically.

These resources need to be weighed up against the savings to get an accurate idea of how “green” they are as an alternative.

Finally, the cost of producing bioplastic seed materials is still higher than creating virgin plastics from petroleum. But this, along with many of the other problems listed are inherent struggles in a growing industry.

If economies of scale and better regulation can overcome these pitfalls, there are some potential prospects in the bioplastics pipeline!

What are the most promising bioplastics?

While learning how to reduce plastic use in your life will always be the better option, there is some hope for bioplastic.

The most promising forms of bioplastics are going to be those which tackle both upstream and downstream inefficiencies within the plastics industry.

Meaning they need to be sourced renewably and degrade efficiently without overly polluting at any stage of their lifecycle. Matching those criteria are several biobased, potentially biodegradable plastics:

Corn starch bioplastic (PLAs)

PLAs can be made by different compositions of rice starch, glycerol, citric acid, and gelatin. They’re potentially biodegradable, and can even be sourced from scraps of crops that we don’t currently have much use for.

This kind of bioplastic is best suited for things like compostable garbage bags and single-use food packaging, and PLAs have already made their way into a variety of products you use everyday!

One of the major downsides of PLAs is that they’ve been found to produce high levels of toxicity upon degrading, although conventional plastic isn’t any better in that regard.

Cellulose-based bioplastic

Designed as a biodegradable material for sustainable packaging, cellulose-based bioplastics are already in use in things like glasses frames, electronics, and thermoplastics among many other applications.

As the name implies, this sort of bioplastic can also be sourced from crop residues, and shows some promise as a moulding material (meaning harder types of plastic like computer cases)

The carbon footprint for this kind of plastic is still high, and the process needs to be optimized as it does still produce high levels of toxins upon breakdown.

Protein-based bioplastics

Protein-based bioplastics are made from plasticised protein chains sourced from wheat or algae protein – and they’re designed to be fully biodegradable (and even edible).

Currently, the major downside of this bioplastic is its short shelf life, but that also means it could be very useful for short-term packaging options such as shipping filler.

Polyhydroxyalkanoates (PHAs)

PHAs are sourced from bacteria – possibly even from waste products and decomposition gasses like methane from our own wastewater!

These are potentially one of the most biodegradable plastics on the market, as shown in recent advancements, although they are still very expensive to produce.

PHAs can be made completely compostable, and they’re also predicted to sink to the ocean floor and efficiently break down, instead of massing within huge plastic vortexes on the ocean surface.

So, there are some interesting prospects, but it seems like bioplastics have a long way to go before they meet the deceitful promises of greenwashing campaigns pushed by the petroleum industry.

Bioplastics aren’t the only solution

While some promising technologies are emerging, at their best they’re working to sustain a level of consumption that is, quite simply, unsustainable.

And unless an alternative material is discovered that can be as cheap and quick to produce as plastic while remaining as versatile and safe to dispose of, bioplastics could remain as mostly a pop-science dream.

Bioplastics may hold some solutions to our plastic problem – but for now, that remains to be seen.

The good news is that there are other avenues to pursue, and there are genuine efforts being made to discover new material technologies! Materials like bamboo also offer a promising break from our reliance on plastic, as a fast growing and compostable crop.

And reports like the one from Pew Trusts puts forward a hope that future plastic could be designed with effective recycling in mind.

While the current state of plastics recycling reflects a half-hearted afterthought at best, the report sees potential in the concept of recycling plastics to keep them out of the environment.

Such an overhaul would take significant cooperation between consumers and industries worldwide, but would include the most important factor of all: a reduction and substitution of plastics – followed by better waste management and processing.

From the production side, reducing chemical complexity and enforcing transparent reporting of chemicals in plastics could lead to a new generation of reusable, recyclable plastics.

Better organization of waste disposal on a consumer level and at the local scale would streamline the sorting process, and investment in a proper recycling system could lead to a more efficient cycle of plastic usage and help solve the issues of production emissions and plastic pollution.