Carbios’ enzyme can break down 90% of PET plastic in 10 hours

Carbios diagram of their PET degrading enzyme. Image courtesy: Carbios
Carbios illustration of how they depolymerize PET plastics using their enzyme. Image courtesy: Carbios
Carbios’ illustration of how they depolymerize PET plastics using their enzyme. Image illustration: Carbios.

A few weeks ago, environmental group Earth Island Institute sued Coke, Pepsi, Nestle, Clorox, Mars, Colgate, Palmolive and other big PET polluters. A new enzyme by Carbios aims to fix that problem by addressing PET plastic pollution.

The lawsuit argues that these companies intentionally mislead the public while knowingly polluting the oceans. 8 to 20 million tons of plastic per year originated from these companies.

In 2016, the Ellen MacArthur Foundation famously published a report that said “plastics will outweigh fish in oceans by 2050”. The main cited reason is that 95% of plastic packaging, worth $80-120 billion a year, we throw out after a single use.

In 2017, National Geographic discovered that only 9% of all the plastic ever made has been recycled. The other 91% is still out there. For some context, we recycle about a third of all the glass we make.

Why is it so hard to recycle plastics?

There are dozens of different types of plastics. Each built for a specific purpose and consisting of different components. For example, polyethylene terephthalate (PET) is used for plastic bottles. Polyvinyl chloride (PVC) is used in pipes. Each has very different properties.

PET however makes up about 20% of the 359 million tons of plastic produced globally every year. And we do know how to recycle it into new bottles and even textiles like clothes, grocery bags, seat belts, etc. So why don’t we?

Well, plastics are made from petroleum. Back in 2015, oil prices too a huge hit and never recovered. This made production of new plastics much cheaper than figuring out and optimizing an entirely new process of recycling.

Another, possibly more important factor, is that the process of recycling PET makes it lose certain mechanical properties, which reduces the effectiveness of its re-utility.

And therein lies the problem at the core of the lawsuit. These companies advertised that they’re using PET due to how easily recyclable it is, but they never actually recycled it. Rendering the entire usage of the material little more than a PR move.

So what do we do?

French company Carbios has been working on recycling PET using an enzyme since 2011. In 2014, they produced the world’s first 100% biodegradable plastic by including an enzyme in the material at the time of production.

Carbios illustration of how they produced the world's first biodegradable PET plastic using an enzyme. Image courtesy: Carbios
Carbios’ illustration of producing world’s first biodegradable plastic using enzyme. Image illustration: Carbios.

At the same time, Carbios has been refining the process by which they depolymerize, or break down, PET plastic waste using their enzyme. Initially, it took them over 24 hours to depolymerize 97% of the material. By July 2018, they brought that down to 16 hours. Now, they can do 90% in 10 hours.

Carbio’s fantastic work was finally published in a prestigious scientific journal like Nature. It’s now only a matter of time before their enzyme becomes widely available and put to where it’s most needed to tackle our increasing growing problem of plastic waste.