Sustainability
Plastic-Eating Bacteria Discovery May End Plastic Pollution
How Were Plastic-Eating Bacteria Discovered?
In 2001, a team of Japanese microbiologists accidentally discovered a plastic-eating bacteria that could one day help to eradicate much of the overwhelming plastic pollution in the world.
The team went out to a garbage dump looking for a substance that would help soften synthetic fabrics like polyester. Many of these fabrics have plastic in them, and the scientists had hoped to find something that would degrade the surface of a plastic compound.
Instead, they found a slimy film that was eating its way right through bottles, toys, and other assorted plastic garbage, and the idea that plastic-eating bacterium could one day be the solution to the overwhelming plastic pollution problem was born.
What is Plastic-Eating Bacteria and How Does it Work?
The plastic-eating bacteria is known as Ideonella sakaiensis, an amazing single-celled organism that can eat plastics as a kind of food.
Plastics are made up of billions of chemical cells sticking together. These are called polymers. Ideonella sakaiensis secret an enzyme called PETase that breaks these polymers down into individual units called monomers. It absorbs the monomers and uses the carbon inside them to grow and reproduce. When the bacteria is sufficiently nourished, it releases what’s left.
Although there are many kinds of plastic, these bacteria are partial to the kind known as polyethylene terephthalate (PET). This is one of the most common types of plastic in use. It’s found in almost every beverage bottle on the market shelves today. It also represents a very large portion of the plastic pollution problem.
It would be great if there was an effective way to degrade those mountains of plastic, but what if there was a way to take it a step further? Instead of just breaking the plastic down, what if a bacteria could be developed to turn it into something beneficial?
How is the Plastic-Eating Bacteria Being Developed?
New bacteria strains can be developed when DNA from one strain is combined with that of another in an attempt to harvest the most desirable qualities, perhaps even creating new capabilities and applications.
A team of scientists from the University of Edinburgh in Scotland have reported making some exciting progress toward engineering a new strain of E. Coli bacteria that is designed to not just eat the plastic, but process it into a white powder called Adipic acid.
Adipic acid has several appealing qualities. It has a light, tangy flavor, which makes it a great additive to powdered fruit beverages, dried cake mixes, and powdered gelatin desserts. Also, because it doesn’t absorb moisture very easily, it will protect these kinds of dried products, allowing them to last longer.
Adipic acid also has applications in other areas, including cosmetics and perfume. Perhaps most importantly, however, it has found a use in the field of medicine. Although it has no medicinal quality in itself, it’s used to create a time-release formulation for medications that must be released into the system slowly.
The experiments at the University of Glasgow had a high success rate with the engineered E. Coli bacteria converting 79% of the plastic’s main component, terephthalic acid, into the more useful Adipic acid.
So, now scientists know it can be done and, with more research, they may just perfect the process.
The next question is, will this bacteria be an answer to the challenges that plastic pollution is creating? Can these microscopic critters help the Earth by stopping plastic pollution?
The Truth About Plastic
In the first part of the 21st century, it’s estimated that approximately 2.5 billion tonnes of plastic garbage have been released into our environment, and experts are only predicting the number will go up from there.
Scientists have found evidence of microscopic plastic fragments being spread to every part of the world. Several huge, floating garbage dumps, filled with mostly plastic, have been identified in oceans around the world and birds and animals are dying with stomachs full of plastic garbage.
Plant roots pick microscopic plastic fragments out of the soil and deposit them in the fruits and vegetables we eat. They’re being blown up into the air and coming back down in the form of raindrops. Babies ingest plastic through their mother’s breastmilk. Microplastic particles have even been found in most human organs.
Finding a way to deal with the plastic pollution problem has never been so urgent. However, there are many innovations currently at work trying to solve this problem. One such method has been taken up by ZeroCircle, a Mumbai-based startup that is developing seaweed into a low-cost alternative to plastics that bio-degrades as soon as it reaches the ocean.
But what is it about plastic that makes it so hard to recycle?
Why is Recycling Not Enough?
Only 5% of nearly 50 million tons of plastic waste generated by the U.S. alone gets recycled. There are also inherent difficulties in the process of plastic recycling itself. Most of the rest ends up in the environment.
The process of recycling itself involves several relatively simple sounding steps. Once plastic waste is collected, it has to be cleaned and sorted, shredded, then melted down. Then it can be made into pellets for manufacturers to reuse in new products.
However, it’s not hard for this system to be thrown off and disrupted. Plastic must be pure and clean before recycling is even possible. When the wrong plastics and additives combine, the recycled product becomes inferior and degraded.
Even when the recycling process works, however, there is another major hurdle. Not all plastics were designed to be recyclable in the first place. For example, plastic grocery bags and straws can’t be recycled because of the kind of plastic used to manufacture them.
Once plastic is recycled, there is still one more problem. Unlike glass and metal, which can be recycled over and over, plastic degrades every time it’s recycled. It can be recycled two or three times at best before its quality has dropped to a point where it can’t be used, anymore. Then it becomes pollution again.
Clearly, it would be great if there was some kind of naturally occurring bacteria that could, through cost-free and environmentally friendly methods, rid us of at least some of this plastic waste so that it’s no longer necessary to rely completely on the imperfect recycling system.
Ideonella sakaiensis (PETase), the plastic-eating bacteria, could be the solution.
Could Plastic-Eating Bacteria Save the Planet?
Scientists have only discovered one species of plastic-eating bacteria that can significantly degrade plastic, and even it only eats certain types of plastic. For this approach to have a significant impact on the problem, scientists will need to find or engineer other species of bacteria that can take on all the other plastics polluting the environment. Although it will take time and money, the answer to whether plastic-eating bacteria can save the planet is a resounding maybe.
Another question being investigated is how, exactly, to use this bacteria. Scientists have to develop ways to deliver it safely and effectively to the many environments that are currently suffering from plastic pollution without damaging anything else. This includes landfills, water, soil, and air.
The problem of plastic waste has taken years to develop, and it comes from multiple sources. It only makes sense, then, that the solution will not be a single, miraculous approach. To that end, scientists are working on other plastic-fighting techniques around the world.
Ocean Cleanup has developed a giant trash-eating robot with the potential to clean 50,000,000 kilograms of garbage every day out of the ocean by 2025. In another exciting revolution, Michelin airless tires are coming out in 2024 and could be the next big thing in reducing the 6.1 million tons of microplastics from conventional plastic tires alone. Plastic-eating bacteria would be a valuable addition to the collection of pollution-fighting tools being developed.
While scientists work toward the bacteria as a viable source of plastic reduction, the rest of the world needs to keep working to take steps toward reducing our own contributions to the overwhelming issue by using more sustainable materials and processes.
Although it could be a while, yet, before the bacteria are ready to render our plastic waste into a more useable substance, the first motivational steps have been taken toward a world where plastic waste is a thing of the past, and we can breathe easily again.
IC Inspiration
More and more manufacturers put their focus into sustainability in their products and environmentally driven legislation continues to evolve, but individuals have also made an enormous impact.
Melati Wijsen is one such person. The fact that she was just twelve years old when she made the decision not to wait any longer for change did nothing to deter her.
Growing up on the Indonesian Island of Bali, Melati was always surrounded by stunning natural landscapes and beaches. However, too often, she and her younger sister, Isabel, found themselves distressed by the growing amounts of plastic all over the island.
She explained to the Imagine5 website “Going to the beach, walking to the rice fields – it was everywhere. All of those moments came together, and my sister and I looked at each other at one point and said: “What are we going to do about it?”
She wanted to start by having single-use plastics banned on her Island home. Not an easy task for anyone, much less a child. However, Melati saw a need too urgent to wait on.
“We know that change is simply happening too slowly.” She explained, “Why does it take six years to ban a single-use plastic bag? We can’t wait until we’re older, or in positions of power ourselves, so we do have to work with those in power now and listen to their stories and convince them of the urgency we feel as the youngest generation.”
So, she and her sister set to work.
They began by writing or calling a variety of business and government departments, both to express their concern and to understand the views and needs of those on the other end of the plastic problem. They also signed and developed surveys strongly encouraging politicians and brand names to introduce change to the way they package their products.
She also helped to develop Youthtopia, a network of other youth who are fighting for change all over the world.
Finally, in 2019, the people of Bali passed a law banishing plastic bags from the Island. Today, stores in Bali post signs stating that no plastic bags are available, and the beaches and rice fields show the difference that policy is making.
Melati is now 18 years old and she’s still working tirelessly at finding solutions for the world’s ever-pressing environmental issues. She is an incredible role model for everybody; a motivational person indeed. If a young girl and her sister can make such a big change, imagine what we could all do, together.