For centuries we’ve been warned of the dangers that lurk deep below the ocean’s surface.
Maybe there’s a horrifying colossal squid, or a Kraken, or an evil villain’s lair.
As it turns out, the reality is far worse.
Hey there polluting population, Jules here for DNews!
The Mariana Trench is the deepest known part of the ocean, stretching down roughly 36,000
feet.
You’d imagine that at those depths, the ocean floor is pristine, almost untouched
by human activity.
Well, I’ve got some bad news for ya.
Turns out, the bottom of the ocean is very, very polluted.
And that’s not some click-bait hyperbole; it is more polluted than some of the most
polluted regions on the surface of the globe.
One probe into the Marianas Trench only had to go about 16,000 feet down to find physical
remnants of actual garbage, not just waste byproducts.
Beer cans, plastic bags, even an entire, unopened can of SPAM was found resting along the Trench’s
wall.
And unless it is removed, this trash can stay down there indefinitely, just piling up.
Plastics, for example, are made up of super-strong carbon to carbon bonds.
These bonds are not prone to being broken down by organic organisms; the material hasn’t
existed in nature long enough for there to have evolved much to break it down.
In 2016 scientists found one type of microbe that can do it, but only for a specific type
of plastic.
And even if we could solve this physical trash problem, there lies an even deeper problem.
Literally.
In late 2016, a paper published in the journal Nature, examined the inhabitants of two of
the deepest oceanic trenches in the world.
Small little crustaceans called amphipods are the perfect study specimen, as they have
fatty tissue, which stores not just fat but also any chemicals that are ingested.
And despite these amphipods being located in two different parts of the world, thousands
of feet below the surface, they were ALL contaminated by what are called “persistent organic pollutants”
or POPs.
“Persistent” meaning that they don’t break down in their environment, and are almost
impossible to remove.
These include chemicals that have been banned from use for decades, at least in the United
States, like polychlorinated biphenyls, which have been shown to be birth defect and cancer-causing.
Other chemicals like pesticides were present as well.
The concentration of POPs was SO high that it was 50 times greater than in one of China’s
most polluted rivers, and was roughly equal to that of Suruga Bay in Japan, an industrial
waste dumping ground.
So, how did this pollution make it all the way down there?
Well the researchers suggest that, in the case of the Mariana Trench, it may have to
do with a little something called the Great Pacific Garbage Patch.
While there are many areas where trash congregates in the ocean, the paper refers to a huge floating
clump of garbage in the Northwest Pacific ocean that floats just near the Mariana’s
Trench, and so plastics and other chemicals end up sinking to its depths.
There’s another theory that the pollution found down there is the result of POP chemicals
entering the food chain.
The amphipods that live in these deep waters are scavengers.
When a larger animal, like a dolphin or a whale, dies, it slowly sinks to the bottom
of the ocean floor, a phenomenon known as carrion-falls.
If this carrion lived in polluted waters, then it could have pollution in its system,
and that pollution would persist in animals that eat it.
The paper does say that this is unlikely, however, given that there is consistent contamination
at different depths.
But either of these theories for how the POPs got so deep would be a huge problem for us
humans.
If these chemicals are so persistent within the food chain, then they eventually reach
our own food supply, contaminating it with our own contaminants.
But it isn’t just bad for us, it’s bad for every living thing.
Ocean pollution saps the amount of oxygen in the water, which can lead to mass death
of marine life.
Certain chemicals can even create reproductive issues for animals in the ocean, so even if
they do survive, they can’t do much for their species.
Society has spent the last few centuries dumping tons of trash into the ocean, including industrial
waste, radioactive waste, munitions, and sewage.
The EPA says, quote, “Wastes were frequently dumped in coastal and ocean waters based on
the assumption that marine waters had an unlimited capacity to mix and disperse wastes.”
But now we’re learning that this isn’t really the case.
The out of sight out, of mind is killing ocean creatures and endangering our own health.
It turns out nowhere is safe from pollution.
Not even the deepest part of the ocean.
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So what actually lives down in the deepest places on Earth?
We have a video all about that, here.
And do you have any other questions about oceans or pollution or science?
Let us know down below in the comments
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