Pollution is one of the biggest environmental problems of our time. Plastic is one of the worst offenders. Maybe you’ve seen–and been confused by–the hubbub over plastic straws. Well, one of those straws can last 450 years in a landfill. Plastic bags, from grocery stores? They’re practically fast, at 20 years–but with even worse consequences. Plastic bags commonly end up in the water. A good scenario is they’ll be swallowed by some ocean animal, choking them. The bad scenario? They’ll sink to the bottom of the ocean, dissolve–and then mix with the plankton, poisoning even more animals. But could there be a solution to the longevity of plastics? (1)
The “Mutant” Enzyme
In 2012, researchers discovered a bacterial enzyme in a compost pile. This enzyme broke down plastics–but scientists from Carbios, a green energy company, worked to kick it up a notch. Now, the enzyme, which has been enhanced in the lab, can break down plastics so completely that they can be used for food products, like water bottles. Usually, the quality of recycled plastic is only good enough to end up in things like clothing, or your Aunt Heather’s Kool-Aid tote bag. But Carbios has teamed up with companies like L’Oréal and Pepsi to make food-grade recycled plastics happen. The process was detail in an article, released in the journal Nature on Wednesday, April 7th, 2020. (2)
The Science Behind It
It started off as the lab version of The Bachelor–100,000 micro-organisms that the scientists believed could make good starting points were brought into the lab. One of the lucky bachelorettes was indeed the compost heap enzyme. Once this enzyme took home that engagement ring, they began a series of experiments to enhance functioning. After their enhancements were complete, this super enzyme was stable at around 162℉ (72℃), which is the ideal temperature for the breaking down of plastics. In fact, this enzyme worked so well it had broken down 90% of the structure of a plastic bottle within 10 hours. The enzyme acts on PET, “Polyethylene terephthalate . . . a general-purpose thermoplastic polymer which belongs to the polyester family of polymers” and is used to make “packaging, fabrics, films, molded parts for automotive, electronics.” (2, 3)
Next Steps
It’s not immediately the environmental miracle it seems. The company projects it’ll be another five years, before it’s ready for wide-scale use. And, at this point, this method is more expensive than fresh plastic, since the materials have to be ground up, then heated. But this hasn’t stopped people from getting excited. Bertrand Piccard, who is the founder and president of the Solar Impulse Foundation, says “I am very pleased that the scientific community recognizes [this] as a financially profitable solution to protect the environment. The use of such technology is as logical as it is ecological.”
In 2018, Senior Oceans Campaigner for Greenpeace UK, Louis Edge said that there must be “commitment from government, corporations and consumers . . .to save our oceans.” Perhaps Carbios’ breakthrough is that commitment. (1, 4)
