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How green is bioplastic?

Mory Touré
November 14, 2018

Bioplastic is meant to be eco-friendly and biodegradable. But on closer inspection, it loses its green sheen. Can packaging made from algae and cooking oil really help fight the plastic scourge?

Plastic bags at teh supermarket checkout
Image: Getty Images/AFP/C. Reyes

If Josefine Staats is to be believed, the red algae Kappaphycus could be our environmental savior — at least when it comes to plastic.

"Algae doesn't need any land to grow. It doesn't need fertilizer or pesticides and it grows quickly," said the entrepreneur from Berlin. Staats runs a natural foods company and sells, among other things, algae snacks.

Now she wants to turn the seaweed into something else: a bioplastic that would look and function just like the oil-based variety. The difference is, it would be biodegradable, and therefore eco-friendly, Staats says.

Read more: Ending plastic waste with big promises?

Staats is still working out the details of her vision and she's not the first person to promote the idea of algae-based plastics. But adequate alternatives to conventional plastics are desperately needed.

Much of the more than 300 million tons of the oil-based material produced each year ends up polluting the environment. The International Energy Agency projects the amount of oil used to produce all of that plastic will soar from 12 million barrels a year in 2017 to 18 million barrels a year by 2050.

Entrepreneur Josefine Staats holding seaweed
Entrepreneur Josefine Staats wants to make plastic more environmentally friendly by making it out of seaweed Image: Josefine Staats

Is bioplastic really better?

Whether bioplastics are a viable solution is open to debate. They're not automatically better for the environment or the climate than their oil-based counterpart, say experts. 

"There are certainly products where biodegradable plastic makes sense," said Franziska Krüger of the German Environment Agency (UBA) but we shouldn't "greenwash it."

Read more: Taking on plastic pollution with molecular recycling

For instance, just because a bag is labeled a bioplastic, doesn't mean it won't end up floating around in the ocean. Depending on what it's made from, the bag might be easily compostable at home, biodegradable only under the right conditions, or might even break down as slowly as traditional plastics — some of which can take up to 600 years to degrade.

Furthermore, crops, such as corn and sugarcane, used to make bioplastics require a lot of land and fertilizer. That could damage soil and mean less land is available to grow food crops.

Infographic showing how long plastic needs to break down in the oceans
Some plastic takes up to 600 years to break down

These are some of the issues addressed at the recent PHA World Congress in Cologne, Germany. PHAs — or polyhydroxyalkanoates — are a kind of polyester produced by bacteria as a source of energy and carbon store to be used when food is scarce.

Read more: Doing Your Bit: A French engineer has created a biodegradable plastic

Lenka Mynarova was one of 165 entrepreneurs and scientists attending the bioplastics congress. She was named 2018 businesswoman of the year in her native Czech Republic and is planning to "upcycle" old frying oil into bioplastic with the help of PHA-producing bacteria.

She says her product won't eat into arable land. "We're not cooperating with any palm-oil producers," Mynarova said at the conference. "We're not wasting any land, we're only using waste."

Doing your bit: Turning ghost fishing nets into bracelets

Shortage of studies

Still, no one can say for sure how plastic based on organic waste will react in the environment. There are no in-depth studies, says Krüger of the UBA.

"There is no guarantee that such bioplastic would completely degrade in nature, or on the compost heap, in the way it does in the lab, where researchers can control the environment," Krüger said.

Read more: Plastic waste and the recycling myth

Right now, recycling companies and local authorities don't have the means to deal with many bioplastics, which have different properties and require different methods of disposal.

"Most bioplastics don't ever have the pleasure of being composted," Krüger said, adding that most composting facilities label bioplastics as a "contaminant" material. That's why products such as organic trash bags made from compostable plastic still aren't a real solution.

A crane in a trash incinerator
Recycling companies and local authorities aren't equipped to deal with bioplastics, so much of it still ends up in incinerationImage: Imago/R. Lueger

And so far, the recycling sector has little incentive to invest in processes to deal with the relatively little bioplastic that's actually out there.

"The effort has to pay off," said Krüger.

In 2017, 2 million tons of bioplastic was produced, according to the Berlin-based industry group European Bioplastic. That figure is set to rise to 2.4 million tons by 2022.

Small steps

But experts say for the bioplastics sector to really take off, crude oil must become more expensive. In recent months, prices have been volatile, recently reaching a four-year high before tumbling again.

"Plastic producers would be well-advised to look for alternatives," said Michael Thielen, a public relations consultant and publisher of Bioplastics Magazine.

Two seaweed farmers in the sea
Seaweed farmers in Sri Lanka where Josefine Staats plans to source the raw material for her bioplastic Image: Josefine Staats

Entrepreneurs like Staats want to be ready with their algae alternatives when companies do come knocking.

The Berliner also wants her startup to double as a development project in Sri Lanka. She plans to support fisherwomen, many of whom lost their husbands in the civil war between 1983 and 2009, to farm seaweed organically.

Read more: European Parliament votes for ban on single-use plastic

It's going to be some time before she can get her first product — bioplastic wrapping for the natural foods company she already runs — to market.

"The technology for the production of algae-based bioplastic is there but not yet fully developed," Staats told DW.

She's currently trying to raise €1 million ($1.14 million) in startup capital and is looking for a lab and scientists to work with.  "So we can at least make a start," she said.