Low density polyethylene (LDPE) is a plastic that is most commonly used in plastic bags. Only 5.7% of it is recycled in the United States each year and it causes massive plastic pollution. But, what if there was a way to naturally degrade this material instead?
Actually, there is! Researchers have found out that the common wax worm can both eat and digest low density polyethylene plastics! These “plastivores” have an intestinal microbe inside of them that could help biodegrade plastics!
Can wax worms eat plastic?
According to a newly published research paper, they can! These small worms, which are the larvae of the greater wax moth Galleria mellonella, have been identified as avid “plastivores” that can ingest copious amounts of soft plastics. They are also able to metabolize the polyethylene really fast, thanks to their intestinal microbiome (a microbiome is the genetic material of all the microbes in any given organism).
Of course, plastic is not part of the was worm’s natural diet. Instead, it is bee’s wax that this worm prefers above all else. The wax simply has the a very similar carbon structure to that of LDPE plastics. And as more and more plastic is ending up in our environment, the wax worm, quite fascinatingly, must have developed the ability to break down this material as well.
It would however take billions and billions of these larvae to combat the global plastic pollution problem, which isn’t really a super sustainable or smooth solution. Instead, the research is focused on understanding the way the intestinal microbiome works and what its exact role is in the breaking down of LDPE plastics.
If science could crack this code, then, with the help of modern technology and bio-engineering, it would perhaps become possible to copy nature and apply this awesome mechanism to combat global plastic pollution.
It is often voiced that this is only addressing the symptom, not the disease of plastic production itself. But All Good Newz wants to offer you a different, more positivist approach to this topic!
It’s simply not a question of either or! Undoubtedly, we as a civilized, global society must find new and highly sustainable ways of living. And we must certainly move away from plastics.
However, such a process demands a certain amount of time. In 2017 alone, an estimated 348 million tonnes of plastic material was produced, which we will have to deal with. And in order to do so, such valuable applications should be taken advantage of, in order to speed up the reduction of the plastic that is already out there.
Because even if the world would stop producing LDPE plastics by tomorrow, there are still billions, perhaps trillions of pounds and pieces of plastic out there, which we will have to get rid off! Finding effective and fast ways of plastic biodegradation is essential to our flora and fauna. That’s where the wax worms’ amazing plastivore capabilities and microbiome could come in.
What does the plastic the wax worm eats turn in to?
After the worm has ingested the plastic, it quickly metabolizes it, thanks to its intestinal microbiome. The researchers then observed that the wax worm excreted glycol. Hence, they could draw the conclusion that the worm’s metabolism breaks down the polyethylene into ethylene glycol, which is an odorless, colorless liquid that biodegrades rather quickly.
What exactly is low density polyethylene (LDPE)?
Low density polyethylene is a thermoplastic that was first produced in 1933. It is widely used to this day, despite strong competition from other, more modern plastic materials. Currently, the global LDPE market is worth about $35 billion annually.
Besides being used to produce billions of plastic bags every year, LDPE is most commonly used for the production of dispensing bottles, wash bottles, plastic containers, tubing, and plastic components in computers.
LDPE has a very good resistance to bases, vegetable oils and acids. It can withstand temperatures of up to 80 °C (176 °F) quite easily and is rather transparent, flexible and tough. These are two main reasons low density polyethylene plastics are used so frequently in the packaging industry; they can hold virtually anything and you can microwave food in LDPE containers without them melting.
Due to its resistance and resilience, it degrades at a very slow rate and can take hundreds of years to decompose. And even when it reaches that state, low density polyethylene does not biodegrade fully, but merely breaks down into smaller pieces (microplastics), which remain in the environment yet further.
How much LDPE is recycled globally each year?
Optimally, if we were to move away from plastics, we could still reuse the plastic material that has already been produced over and over again. This would result in a natural reduction of plastic and plastic waste, as there would be more and more sustainable and eco-friendly alternatives on the market.
Unfortunately, low density polyethylene recycling does not really equal that equation. Currently, only about 9% of LDPE materials are recycled globally each year. In the U.S., that number is a mere 5.7%. This means that there is plenty of plastic waste out there; in the streets, the forests, the lakes and rivers, and in our oceans.
Some countries have come a long way when it comes to low density polyethylene recycling and the reusing of waste in general. But many others lack far behind and improvements in these regards will certainly not happen over night in these regions.
Related Article: The Environmental Sustainability Consultant Who Changes the World
Hence, other, more short-term solutions will have to be developed in order to be able to deal with this gigantic problem that becomes more and more visible. Such short-term solutions are by no means the end of the road! On the contrary, they allow to open up ways to find long-term and highly sustainable solutions to such issues.
These do however take time, and so something fast and efficient will have to be done in the meantime!
Plastic degradation by bacteria and microbiomes
As the research paper has stated, such a solution could be found in the wax worm’s intestinal microbiome.
Thus far, not enough data has been collected in order to really pinpoint the exact way in which the worm’s microbiome seems to be able to biodegrade LDPE plastic material. But the results of this latest research strongly suggest that the microbiome plays a very important role in the initial biodegradation process of LDPE.
The real challenge seems to be to figure out a way of using the power of the microbiome outside of the worm’s organism. The LDPE biodegradation is much more effective within an insect host, which means that science will have to come up with a way to create a similar host environment. In vitro tests have hitherto only shown rather slow rates of biodegradation.
But if such a way can be found, perhaps via robotics that can mimic the in vivo environment of the plastivores, entire new worlds of sustainability and environmental protection would open up themselves to us!
Feature image by Rasbak – Wikimedia Commons, CC BY-SA 3.0,