Bioplastics: What they are, and are not
It has now become fashionable for FMCG giants to brand their product packaging as ‘biodegradable’. But are they really?
At the EcoVia Ltd plant in Tongi, its CEO Rashik Hasan was showing us the production unit and various forms of packaging items. Shopping bags, stationery carriers, apparel bags – they all looked like usual polybags you see in the market.
Except "these bags originate from the cotton plant, and they go back to nature as compost," Rashik said.
Faced with the serious health and environmental threat of conventional plastics, the worldwide buzz surrounding bioplastics is obvious. It is still a budding global market, but growing fast. In 2021, the global production was 2.4 million tons [half of this in Asia], and is forecast to be about 7.5 million tons in 2026.
In Europe, consumer-level bioplastic products are making their way to the market more frequently than ever. A European Union policy framework is on the way to formalising protocols for their sustainable consumption.
And why the buzz exactly? They are claimed to be eco-friendly [biodegradable], have lower carbon footprint [production steps cause less CO2 emission] – which their plastic counterparts are not.
As Bangladesh is at the forefront of climate vulnerability, the government has consistently pledged to take steps for environment protection and better management of plastic-waste. Very recently, special focus has been put on regulating single-use plastics.
Amidst all this, bioplastics are considered a key to achieving sustainable goals.
What are bioplastics and why are they important?
Simply put, these are plastic materials made from chemicals that are not human-made, but originate from nature. Rashik Hasan explained the sources, which include "cellulose from cotton plants and jute, starch from corn syrup and potato," certain chemicals from food waste, sewage waste, animal fats and oils – any renewable biomass sources.
The conversation around bioplastics has become important because of the looming microplastic complications that come with traditional plastics.
The biggest issue with plastics is that they take tens to hundreds of years to degrade [breaking down into the chemical it originated from]. Many of them break down only into small beads of 5mm size or lesser, while being chemically intact. These particles are known as microplastics.
On an average, 3.1 million tons of microplastic particles are thought to be leaking. That is more than the amount of total bioplastics production.
Microplastics are now present "in every part of human existence" – in the cloud, in the ocean, Antarctica ice, in drinking water, food, even human breast milk.
These are serious threats to human health – increasing risk of metabolic disorder and gene mutation, weakening immunity. Children are especially vulnerable, because exposure to microplastics from an early age is likely to cause stunted development.
Strict reduction of plastic production is a must. So is finding alternatives to plastics, wherever possible. This is where bioplastics are becoming important.
A highly cited 2020 study at the University of California showed that while the degradation of day to day use plastics in land occur at a very slow rate [0-22 micrometre a year], biodegradable bioplastics decay at a much faster rate [100-320 micrometre a year].
Is their production different to traditional plastics?
Everyday-use plastic goods are derived from chemicals known as polymers. The major sources of these are fossil fuel refineries – obtained as byproducts of refined fuels. Meanwhile, the starting materials of bioplastics come from plant-based sources.
Like, as Rashik continued, "for our bioplastics, we collect cotton dust leftovers from apparel industries, which we process using enzymes [proteins that help initiate a chemical production] to get cellulose."
Unlike traditional plastics, continuing the greenness may be possible throughout the production of bioplastics.
"To make sure we get final products that are plastic-like films, we mix soybean oil, in place of fossil fuel, and bio-based catalysts," Rashik added.
Caution: 'Bio-' does not always mean 'biodegradable'
Because the concept of bioplastics is relatively new, the sector is also clogged by confusion, misconceptions, and false claims.
Dr Mahfuzul Hoque, a Bangladeshi scientist on sustainable materials currently working in Canada, said "it is critical to clearly set the difference between when a plastic commodity is 'biodegradable' and when it is not."
Normally, he said, there must be "a timeframe between the disposal and the material breaking down" into biomass, water and CO2. This timeframe, according to Rashik is, "180 days after disposal" – meeting the international standard.
Beverage giants often brag about their newly marketed "bio-PET" bottles - the starting material for these is collected from sugarcane. However, bio-PET plastics are not biodegradable.
It is widely accepted that cellulose bioplastics, which Rashik and his team is working on here in Dhaka, are broadly biodegradable and compostable [breaking down to water and inorganic elements important for soil's nutrition].
Japan's recent approaches for mainstreaming bioplastic products made of cellulose are considered to be a game changer. To do that, they are innovating new methods to extract cellulose from agricultural wastes like banana peel and sugar-beet pulp.
Other biodegradable plastics may include certain specific chemicals like PLA (poly-lactic acid) - which is
Disposal needs composting facilities
The bigger question is – can we simply throw bioplastics anywhere on the land, or water and expect them to break down themselves?
Not really.
"The actual biodegradable bioplastics in the market are to be disposed of at specialised composting facilities," Mahfuzul suggested.
In short, these are to be separately disposed in industrial composting facilities at controlled moisture and temperature after use, "or else there is not much benefit."
While research is underway and there may be developments in the coming decades, right now claims such as bioplastics are "biodegradable at any environmental conditions is very much exaggerated – worse, false," he warned.
Rashik suggested the same. "For example, our buyers are international RMGs who are certified to dispose of bioplastics at specialised facilities. This is a crucial aspect of our business - that we ensure the end fate is forming composts."
'Greenwashing'
Rashik gave an example of what greenwashing may be like.
"There are risks of counterfeit products, where, say, bioplastic packages are mixed with look-alike normal plastic packages, and sold as bioplastics in lots."
That not only complicates the disposal, but paints a very negative impression if products like these get exported abroad.
The second manner of greenwashing may come as, you may have guessed already, selling non-biodegradable bioplastics as biodegradables.
"In fact, this is already happening" suggests Mahfuzul. "We will someday see bioplastics that decompose in your house's backyard. Right now, unless your municipality has central compost facilities – many will be fooled by products that are labelled "100% biodegradable"".
His comments align with a recent three-year trial study at Plymouth University in the UK. It was found that many commercially sold 'compostable' bags stay intact regardless of where they were left – landfill, soil or seawater.
These matters get more serious when confrontation erupts between academia and corporations. An instance of such a case happened in 2018 when a senior academic from the same university demonstrated that claims from British companies that certain salt-additives containing 'oxo-' plastics are biodegradable are downright false.
The BBC was severely criticised for covering such a topic – particularly when it is not yet proven that oxo-plastics, which are merely traditional plastics only going through certain chemical modification, are biodegradable.
Worryingly though, the air of greenwashing has hit local suppliers too, as the website of a bioplastic sidekick of a major Bangladeshi RMG touts their oxo-degradable plastics as 'biodegradable'.
Consumer-responsibilities
Despite the challenges and confusion, there is no denying that bioplastics will be major tools in preventing plastic pollution in the coming decades. But for that, much preparation is needed.
Consumers are crucial in solving the bioplastic puzzle. Because "the final treatment of plastics and bioplastics are different, municipalities need to ensure that they collect the two plastics types separately," Mahfuzul said.
For this, households need to become used to dumping their litter separately – like the Western countries. "This is a monumental task, as people in Bangladesh are not much familiar with the concept of segregated waste-dumping. But if we want to make a transition towards bioplastics, this has to start at some point."
Proactive school- and community-based campaigns will help the cause massively, he suggested.