Coral found to prefer eating microplastic to natural food

Coral found to prefer eating microplastic to natural food
Astrangia. Credit: Stephen Cairns et al. An illustrated key to the genera and subgenera of the Recent azooxanthellate Scleractinia (Cnidaria, Anthozoa), with an attached glossary, ZooKeys (2012). DOI: 10.3897/zookeys.227.3612. Creative Commons Attribution 3.0 Unported license

A team of researchers from Boston University, Roger Williams University, the New England Aquarium, Boston Children's Hospital and Harvard Medical School and UMass Boston, reports that one type of coral prefers to eat microplastics over natural food. In their paper published in Proceedings of the Royal Society B, the group describes experiments they conducted with Astrangia poculata, a type of coral, and what they found.

In recent years, there have been many reports describing the damage that plastics are doing to the environment—whether in landfills, atop high mountains or in the deepest part of the ocean. It seems plastics have made their way to every part of the planet. And now, that list includes tiny coral polyps.

As part of their study of corals and how they are faring in the face of warmer and more acidified oceans, the researchers collected several specimens of A. poculata—they live just off the eastern coast of the United States. The specimens the team collected were found off the coast of Rhode Island, near the city of Providence. The site was selected due to its proximity to a large urban area, which meant there was a lot of in the water. The researchers focused on microplastics, tiny bits smaller than five millimeters across. They suspected it could wind up inside of corals.

Back in their lab, the researchers cut open the specimens and discovered that every single polyp contained at least 100 bits of microplastic—the first recorded instance of coral consuming plastic in the wild. Next, the team dumped microbeads into tanks of lab-raised coral along with their normal food, shrimp eggs. When they later cut the corals open, they found that there was twice as much plastic in their polyps as there were shrimp eggs. The researchers claim this shows the coral has a strong preference for plastic bits over natural food.

In a follow-up experiment, the researchers dunked a batch of plastic beads into the ocean, which allowed bacteria to form a biofilm on them. They then laced the biofilm with E. coli and fed the beads to lab-raised corals. The team reports that even though the corals spit out the beads two days later, they all died from E. coli infections. The team suggests this finding indicates that a lot of might be dying from infections carried by plastics.


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More information: Randi D. Rotjan et al. Patterns, dynamics and consequences of microplastic ingestion by the temperate coral, Astrangia poculata, Proceedings of the Royal Society B: Biological Sciences (2019). DOI: 10.1098/rspb.2019.0726

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Jun 27, 2019
microplastics are as inert as bits of quartz (sand) and respond much the same within organisms.

Worried about plastics in the ocean. Go complain to China, Philippines, Indonesia, India, Malaysia, Vietnam, Cambodia, Myanmar.

Jun 27, 2019
We need to end the use of *disposable* plastics globally just as we ended the use of ozone destroyers.

Jun 27, 2019
Why not make it digestible and give it nutrition content?

Jun 27, 2019
Back in their lab, the researchers cut open the specimens and discovered that every single polyp....

In a follow-up experiment, the researchers dunked a batch of plastic beads into the ocean, which allowed bacteria to form a biofilm on them. They then laced the biofilm with E. coli and fed the beads to lab-raised corals. The team reports that even though the corals spit out the beads two days later, they all died from E. coli infections.

So, the only coral to actually die, were at the hands of these "scientists".

Jun 27, 2019
So, the only coral to actually die, were at the hands of these "scientists".
says antigoracle

It certainly seems that way.
Petroleum is used to make plastic, and petrol came from the oils of plants that died long ago. These 'researchers' KILLED these corals with E.Coli by introduction of the bacteria that is a known killer. Absolutely disgusting.

Jun 27, 2019
microplastics are as inert as bits of quartz (sand) and respond much the same within organisms.

Worried about plastics in the ocean. Go complain to China, Philippines, Indonesia, India, Malaysia, Vietnam, Cambodia, Myanmar.
says Shootist

Only western nations are scolded by the AGWhysterians. We have yet to see a delegation from the IPCC flying (on fossl-fueled airplanes) into those countries that you mentioned to make them STOP polluting their rivers, streams and the ocean with plastics and other junk.

JRi
Jun 28, 2019
I think they put wrong emphasis on the things they studied. What I understand, the most important observations were:
1) Corals like to eat plastic micro beads at least as much as their natural foot shrimp eggs.
2) However, plastic does not suffocate them, they just spit it away after awhile.
3) Ingested material contaminated with dangerous bacteria kills the studied coral specimen.

Jun 28, 2019
Yeah, it's all those evil yellow people with slanty eyes. /s

Jun 28, 2019
Worried about plastics in the ocean. Go complain to China, Philippines, Indonesia, India, Malaysia, Vietnam, Cambodia, Myanmar.

We don't have much to complain to them as we are just exporting our plastic there cheap and then our hands are washed of the problem. Good thing that recyclable plastic in becoming a big thing and people are realizing what plastic does in nature.

Jun 29, 2019
Hygiene in New England IS terrible. Corals should be VERY AFRAID. Seriously, this "experiment" (if being reported correctly) is catastrophically flawed. One could smear E. Coli on anything and feed it to most organisms and they would die. What makes microplastics any different? If the corals are eating the plastic WITHOUT the E. Coli and are NOT dying, could this even be seen as an environmental benefit, because the corals prefer them and perhaps are saving some other species which cannot safely ingest the plastic?

Jun 29, 2019
microplastics are as inert as bits of quartz (sand) and respond much the same within organisms.


Not really. Plastics are chains of hydrocarbons, while sand is silicon dioxide.

Plastics are in principle edible to organisms, it's just that not a lot of them have the metabolism to eat them. A few hundred million years ago during the Carboniferous period, trees and treelike plants evolved a kind of plastic (lignin) that was similarly inedible to nearly all organisms and so the trees would not rot. It took a while for fungi and bacteria to develop the necessary chemical pathways to break down lignin to eat trees, and in the mean while all the non-decomposing trees that had died fossilized and sequestered so much carbon that the climate cooled down and the sea levels dropped.

It's those trees that we now pump up from the ground as oil and natural gas, and turn into plastic, which is inedible to the current organisms.

Jun 29, 2019
However, since the problem has been solved once already (lignin is very similar to synthetic plastics), I don't doubt in a number of generations a whole bunch of tiny organisms start to eat up all the micro-plastics in the oceans and in doing so become themselves edible to other organisms, and the plastic becomes a part of the food chain.

Jun 29, 2019
@Eikka, ants deposit formic acid which solves (in the chemical sense) lignin. And the evolution of ants proceeded from that time; both ants and trees are quite prolific, you'll note.

Jun 29, 2019
And if you're wondering about termites, they evolved from cockroaches (or perhaps vice versa) instead of wasps (like the ants) and about 100 million years later than ants, and their big thing is being able to eat cellulose.

Jun 29, 2019
Last but not least, the problem isn't whether coral can eat the microplastics. The problem is whether they can digest it. In other words, it's clogging up their guts and they die from it.

Jun 29, 2019
don't doubt in a number of generations a whole bunch of tiny organisms start to eat up all the micro-plastics in the oceans
Of course they already exist

"The original Ideonella sakaiensis bacterium is far from the first living species to possess plastic-eating proclivities. Waxworm caterpillars have been found to break down plastic in a matter of hours, and mealworms possess gut microbes that eat through polystyrene."

-But making them biodegradable by existing organisms makes more sense and is probably safer.

"Two basic classes of biodegradable plastics exist:[2] Bioplastics, whose components are derived from renewable raw materials, and plastics made from petrochemicals containing biodegradable additives which enhance biodegradation."

I read a scifi novel some years back about some anarchists who concocted a bug that digested plastic and rubber. They dispersed it by driving down highways and spraying the roads. Mayhem ensued.

Jun 29, 2019
@Eikka, ants deposit formic acid which solves (in the chemical sense) lignin. And the evolution of ants proceeded from that time; both ants and trees are quite prolific, you'll note.


That's kinda missing the point. When trees and plants died, or shed leaves, twigs etc. there was a time when the micro-organisms could not eat the remains.

The organic residue would break down as micro-organisms ate the cellulose and the sugars, leaving behind the lignin matrix they could not digest, and this was then further broken down mechanically and photochemically into stuff very much like the microplastics we have today - except there was much more of it than whatever plastics we could ever hope to produce. It eventually became sedimented and fossilized into the carbon, oil and gas, we use today, but back then it would have been on the surface and in the oceans, just floating about.

Jun 29, 2019
Last but not least, the problem isn't whether coral can eat the microplastics. The problem is whether they can digest it. In other words, it's clogging up their guts and they die from it.

Da Schitts, the knob gobbler, brays again. Does your boyfriend know of your penchant for pulling shite out of your ass?

Jun 29, 2019
@antigoracle
@S_E_U.

You both missed the salient point. The bacterial film (akin to the natural biofilms of all kinds, even in your body during infections) forms NATURALLY on micro plastic surfaces in the ocean; and hence provides the environment/substrate for E.Coli types to also attach there....and eventually infect the coral polyps unfortunate enough to ingest them via there normal sea-water-filtration system.

The fact is, normal 'food' (like shrimp eggs) do NOT have E.Coli attached to them because their egg-surfaces discourage such detrimental bacteria as E.Coli from attaching....else the eggs would not survive long enough to hatch if they were so easily infected.

The difference is that microplastics is porous and NOT self-cleaning like most natural egg-surfaces in the ocean have evolved to be to some extent. OK?

Try and more objective and in-depth with your reading/comprehension in such important matters as these in future, guys. Thanks. Good luck to us all. :)

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