Plastic pollution goes out of control every year, more than 8 million tonnes Synthetic polymers enter the ocean, some of them sink to the groundBack to beachor collect at stuckBig portions It’s not easy to calculate.
All that missing plastic is a mystery, but some researchers suspect hungry microbes are partly responsible.
Experiments in the laboratory have now shown that a type of marine bacteria known as Rhodococcus redIt can slowly decompose and digest the plastic it is made of Polyethylene (PE).
widely used in packaging, Polyethylene is the most widely produced plastic in the world, and it is not clear whether Wrapping In these litters in the wild, new research confirms they are capable of at least that.
Previous lessons have found strain Wrapping They float on dense cell membranes above sea plastic. Moreover, the initial search in 2006 I suggest plastic underneath Wrapping It was collapsing at a faster rate than usual.
New studies confirm that this is the case.
“This is the first time we have shown in this way that bacteria actually digest plastic into carbon dioxide and other molecules.” Say Microbial ecologist Maaike Goudriaan of the Royal Netherlands Institute for Marine Research (NIOZ).
To simulate the natural way plastic decomposes at the surface of the ocean, Guderian and his colleagues exposed their plastic samples to ultraviolet light and placed them in artificial seawater.
“UV treatment is necessary because we already know that sunlight partially degrades plastic into bite-sized pieces of bacteria,” he said. Explain Guderian.
After that, the team introduced the strain Wrapping to the scene.
By measuring the levels of the carbon isotope released from a degrading plastic called carbon-13, the authors estimated that the polymer in their experiments degraded at a rate of 1.2% per year.
The team couldn’t be sure how much plastic the UV light was eroding compared to microbial activity, but it was clear that bacteria played a role. The bacterial samples after the experiment showed a carbon-13 enriched fatty acid membrane.
The rate of plastic decay was determined in this study very slow to fully solve the problem of plastic pollution in our oceans, but show where some of the missing plastic on our planet might be going.
“Our data show that sunlight can reduce significant amounts of all the floating plastic that has polluted the oceans since the 1950s.” Say Microbiologist Annalisa Delery.
The microbes can then enter and partially digest the sun’s remains.
Since 2013, researchers have been doing just that be warned It’s possible that microbes thrived on plastic patches in the oceans, forming an artificial ecosystem that became known as the plastosphere.
There is even evidence to suggest that some of these microbial communities Adapt To eat different types of plastic.
Previous studies have identified certain bacteria and fungi, on earth And at seaLooks like eating plastic. But while this knowledge can help us better Recycle our waste Before ending up in the wild, its other uses were controversial.
Some scientists have suggested shooting plastic gum at pollution spots, such as A huge patch of trash in the Pacific Ocean.
others I’m not sure this is such a good idea. engineered enzymes And bacteria Deconstructing plastic may sound like a great way to get rid of our waste, but some experts are concerned about the unintended side effects it has on natural ecosystems and food webs.
After all, breaking plastic isn’t necessarily a good thing. Microplastics are much more difficult to clean up than large pieces, and these tiny residues can find their way into food webs. A filter feeder, for example, may accidentally pick up small pieces of plastic before the microbes do.
inside study In 2020, every seafood sample tested on the Australian market contained microplastics.
What does it do to human or animal health completely unknown.
“Prevention is much better than cleaning.” Debate Guderian.
“And only we humans can do that.”
The study has been published in Marine Pollution Bulletin.
