The Korea Herald


[Weekender] The truth about biodegradable plastics

Despite being touted as solution to plastic waste problem, biodegradable plastics are not given chance to decompose

By Kim Byung-wook

Published : May 29, 2021 - 16:01

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(Agricultural Research Service) (Agricultural Research Service)
For average customers, one of the easiest ways to pursue a green lifestyle is to purchase eco-friendly products.

To target these customers and raise their brand images, companies in South Korea are rolling out eco-friendly products one after another, including some made of biodegradable plastic.

Typically made from natural materials such as corn starch, biodegradable plastic is designed to break down naturally when it goes to landfills.

However, these efforts – and extra expenses -- might be in vain, as most of these products are incinerated after they are thrown away. Even if they end up in landfills, it is likely that they don’t break down as promised, since none of the landfills in South Korea provides conditions suitable for them to biodegrade.

“Most of the waste is either incinerated or recycled, so whether the product is biodegradable isn’t really important. What really matters is whether the product can be circulated again and how carbon emissions can be minimized when incinerated,” said Hong Su-yeol, head of Resource Recycle Consulting.

Biodegrade? Not in every environment

According to the guidelines by the Ministry of Environment, biodegradable plastic is categorized as consumer waste and therefore should be put into a standard plastic garbage bag when thrown away.

In 2018, Korea tossed out 25,572 metric tons of consumer waste in these plastic garbage bags each day. Some 52.7 percent of that waste was incinerated, while 28.9 percent went to landfills and 18.4 percent was recycled.

Moreover, a recent report by a civic group Green Korea suggests that biodegradable plastic is a blind spot in the nation’s recycling system and it’s questionable whether it is properly sorted.

According to the report, biodegradable plastic is legally labeled as a product “difficult for retrieval” and “unfit for recycling,” along with diapers, cigarettes and chewing gum.

Those products are legally exempt from recycling obligations, but fees are charged instead. However, biodegradable plastic is neither subject to the recycling obligations nor environment fees.

Even if biodegradable plastic reaches a landfill, there is no guarantee that it will decompose properly.

In Korea, the word “biodegradable” can be used for plastic that decomposes at a special, high-temperature environment in a lab -- meaning a reduction of substance of more than 90 percent in six months at a temperature between 56 degrees Celsius and 60 degrees Celsius. But there is no landfill in Korea that provides these temperatures.

For the government, establishing a landfill that supports the decomposition of biodegradable plastics is a dilemma, as there isn’t enough biodegradable plastic waste yet. Data from Plastics Europe suggests that bio plastic account for just 1 percent of global plastic production.

On top of that, some experts raise doubts over whether the new breeds of “eco-friendly” plastics are any better than typical plastic products.

In October, a study conducted by Nanyang Technological University in Singapore found out that single-use, regular plastic bags have actually “lower environmental footprints” compared to reusable plastic bags.

In the study, researchers conducted a life cycle analysis of five types of bags to evaluate the environmental impact associated with their production, distribution, transportation, waste collection, treatment and end-of-life disposal. The study found that reusable plastic bags, which consume “immense amounts of water and natural resources,” would need to be reused four times to offset the emissions equivalent to that of the creation of one single-use plastic bag. This study implies that bio degradable plastic, which is mostly incinerated after single use, may not be eco-friendly compared to typical plastic.

Jason Locklin, the director of the New Materials Institute and a professor at Georgia University, criticized that biodegradable plastic is “tremendously confusing, not just to the consumers, but even to many scientists,” and can make recycling more complex than it needs to be.

Part of a mega trend

Despite mounting pessimism over biodegradable plastic, however, the reason why companies pursue biodegradable plastic business is simple – it befits the direction they are heading and is also good for business.

Amid the ever-growing global awareness over plastic consumption, companies want to show consumers that they care for the Earth too.

According to the Environment Ministry, of 956 companies that received biodegradable plastic certifications in 2019, 89.1 percent or 852 companies saw their revenue grow 20 percent on average.

Hwang Sung-yeon, a bio-plastic expert at the Korea Research Institute of Chemical Technology, warns that customers should be aware of deceptive marketing tactics using biodegradable plastic.

Hwang cited 3M’s natural corn mesh scrubber as an example. On the package, 3M describes in Korean that the product is “100 percent made by corn starch.” However, it’s the mesh scrubber on the outside that is made by corn starch, not the sponge inside the mesh.

A local food giant Deasang’s Chungjungwon promotes that its seafood stew tea bag product uses a tea bag made of 100 percent of corn starch, which is true, but the tea bag is actually enclosed inside a plastic packet.

“More than 70 percent of biodegradable plastic is incinerated because there is no proper landfill. Instead of shifting the burden onto customers, manufacturers should establish their own landfills,” Hwang said.

On a brighter note, extensive research is underway around the globe to help biodegradable plastic overcome its limitations and decompose easily under more usual conditions.

Last month, scientists at the University of California, Berkley, announced last month they have found a way to biodegradable plastic to really disappear by pouring warm water.

The research findings showed that at room temperature, 80 percent of biodegradable plastic degraded entirely within about one week. At 50 degrees Celsius, the plastic decomposed completely within six days.

Last year, French researchers led by professor Alain Marty at the Universite de Toulouse engineered a mutant bacterial enzyme that can break down plastic bottles 90 percent within 10 hours.

In Korea, to tackle masks piling up amid the pandemic, the Korea Research Institute of Chemical Technology in March developed a mask filter that breaks down naturally 100 percent within a month.

According to 360i Research, the global biodegradable market is expected to grow to $8.9 billion by 2025 from last year’s $5.1 billion.

By Kim Byung-wook (