They often end up in the same place – the incinerator, said Associate Professor Tong Yen Wah from the Department of Chemical and Biomolecular Engineering at the National University of Singapore (NUS).
Biodegradable plastic wastes make a difference to the environment only when they are buried in landfills, he added.
“In these situations, these plastic bags can degrade faster as compared to a regular polyethylene plastic bag and will not affect the environment as much. Overall for Singapore, it might even be more expensive to incinerate biodegradable plastics,” said Assoc Prof Tong. He explained that this is because some biodegradable options take more resources to produce, which make them more expensive.
The opinion squares with what Dr Amy Khor, Senior Minister of State for the Environment and Water Resources said in Parliament in August – that a life-cycle assessment of single-use carrier bags and disposables by the National Environment Agency (NEA) found that substituting plastics with other types of single-use packaging materials is “not necessarily better for the environment”.
“In Singapore, waste is incinerated and not left in landfills to degrade. This means that the resource requirements of oxo-degradable bags are similar to that of plastic bags, and they also have similar environmental impact when incinerated.
“In addition, oxo-degradable bags could interfere with the recycling process when mixed with conventional plastics,” said the NEA study.
Oxo-degradable plastics quickly fragment into smaller and smaller pieces, called microplastics, but don’t break down at the molecular or polymer level like biodegradable and compostable plastics.
The resulting microplastics are left in the environment indefinitely until they eventually fully break down.
The European Union (EU) has in fact decided in March to ban items made of oxo-degradable plastic alongside a ban on single-use plastics.
In making the decision, the EU said oxo-degradable plastic “does not properly biodegrade and thus contributes to microplastic pollution in the environment”.
The measures will take effect in 2021.
STILL KEEN ON ALTERNATIVES
Although biodegradable alternatives may not make a difference to the environment, several companies here have already made the switch.
A BreadTalk Group spokesman told CNA that 78 per cent of plastic bags used by the group’s bakery division is biodegradable.
The takeaway boxes used at Food Republic outlets and the cups used at Toast Box outlets are also biodegradable, he said.
“As a key player in the F&B business, BreadTalk Group remains highly committed to gradually increase our biodegradable packaging options for consumers. However, we are also conscious of the reality that certain local cuisines will still require plastic lids for easy handling.”
Similarly, caterer Neo Group has implemented biodegradable cornware utensils since 2010.
“The cost of changing our disposable ware to biodegradable cornware was higher, but we believe in doing our part to save the Earth, which is why our founder initiated the move to implement the change nine years ago,” said a Neo Group spokesman.
The spokesman added that Neo Group’s company-wide long-term goal is to go paperless and reduce the use of plastic by 30 per cent in its day-to-day operations.
Despite the belief that they are better for the environment, experts said a larger carbon footprint could be created in producing them.
“Some biodegradable plastics may require more resources to produce and that would inevitably incur a higher carbon footprint,” said Mr Liow Chean Siang, head of environmental certifications at the Singapore Environment Council.
He added: “Consumers may have less guilt in using such bags but ultimately this could have little impact on reducing carbon footprint or greenhouse gas emissions.”
Many biodegradable materials can only break down under specific circumstances, many of which cannot be provided by natural environments, said general manager of Zero Waste SG Pek Hai Lin.
According to Ms Pek, the carbon footprint for cornware is high compared to regular plastic, and based on the NEA study, it is not clear whether it can be recycled.
“Furthermore, cornware is made from corn starch extracted from kernels, which makes one wonder if the same resource could have been used for food instead of convenience,” she added.
Dr Alexander Jackson, a plastic scientist from A*STAR, thinks companies are rushing to find alternatives to single-use plastics without fully considering the complete environmental impact.
“The producers themselves would be the best people to ask, do they know how truly environmentally friendly these products are?”
BOLDER STEPS NEEDED
By 2020, businesses will have to report the type and amount of packaging they put into the market to the NEA, and outline their plans for reducing it. This applies to brand owners, manufacturers, importers of packaging and packaged goods, as well as supermarkets with an annual turnover of more than S$10 million.
An extended producer responsibility framework for packaging waste will also be launched by 2025, the Ministry of the Environment and Water Resources (MEWR) announced on Friday (Aug 30).
Assistant Professor Marvin Montefrio who lectures on environmental studies at Yale-NUS believes that there are still merits in the shift towards biodegradable alternatives.
He said: “I imagine Singapore to be a significant market for the plastics industry, just seeing how pervasive single-use plastics are in the retail sector.
“If the demand changes or if there are regulations that control the use of non-biodegradable single-use plastics in Singapore and elsewhere, imagine how this could potentially influence the single-use plastics and packaging sector.”
But it could be challenging to completely eradicate single-use plastics because they are still necessary in some situations, such as in food packaging or for medical purposes.
“We do need to admit though, that in many other cases they are completely unnecessary, as all they do is just make our lives a little more convenient,” said Asst Prof Montefrio.
“So at some point we do need to make bolder steps beyond just making all single-use plastics biodegradable.”
Published on channelnewsasia.com
The OPA (OXO Biodegradable Plastics Association) comments on this article as follows:
“Singapore is one of the few places in the world where degradable plastic may not be necessary – because in such a small and well-regulated society most of their waste gets collected. However, almost everywhere else, plastic waste gets into the open environment. This is why oxo-biodegradable plastic was invented by the scientists who created plastic, so that it would rapidly convert into biodegradable materials, instead of creating microplastics and lying or floating around for decades.
It is important not to confuse oxo-biodegradable plastic with oxo-degradable plastic, because oxo-degradable plastic is essentially ordinary plastic, which degrades and fragments but does not become biodegradable except over a very long time. The EU has correctly said that oxo-degradable plastic “does not properly biodegrade and thus contributes to microplastic pollution in the environment”, and we should stop using it.
It is also important not to confuse oxo-biodegradable plastic with biodegradable plastic made from food-crops (usually marketed as compostable although they convert into CO2, not compost). Oxo-biodegradable plastic will degrade and biodegrade anywhere in the open environment where oxygen and bacteria are present, but compostable plastic has to be collected and taken to an industrial composting facility. It is correct that compostable plastics do require more resources to produce, and have a higher carbon footprint.
Degradability of any kind is unnecessary for plastic which is incinerated or sent to landfill.
It is correct that replacing plastics with other types of single-use packaging materials is not better for the environment. Plastic is the best choice for most everyday uses, provided it is all collected, or made with oxo-biodegradable technology.