Researchers have discovered “extraordinary” levels of manmade chemicals in the Mariana Trench, which is the deepest place on the planet. Because of how remote the trench is, you would think that it would be mostly undisturbed by human hands, but apparently, that is not the case.
Mariana Trench residents are contaminated
In a study published online on the journal Nature Ecology and Evolution, earlier this week, researchers at the U.K.’s Newcastle University said they found that crustaceans living the Mariana Trench are contaminated. They studied small crustaceans living in the trench that were collected by a robotic submarine.
The researchers also studied crustaceans living in the Kermadec Trench and found that both sets were contaminated with 50 times more toxins than those living in China’s rivers. China is well-known for its air pollution, and its rivers are also very contaminated, according to scientists.
Two toxins found in the Mariana Trench
The U.K. researchers found two main types of industrial toxins in the Mariana Trench. Both were banned in the late 1970s, but they don’t break down in the environment. Because of this property, they’re referred to as persistent organic pollutants. Scientists have also found these same two chemicals in dolphins and killer whales in western Europe and in the Inuit people living in Canada’s Arctic region, reports The Guardian.
Researchers believe that the chemicals end in the Mariana Trench after contaminated animals die and their bodies end up in the trench. They also suggest that plastic particles are falling to the bottom of the ocean, noting that the chemicals tend to stick to plastic trash and are able to repel water. The study’s authors explained that the Mariana Trench is home to “incredibly efficient scavenging animals,” which means that they “turn up in huge numbers” to devour every “little bit of organic material that falls down.”
Further, researchers aren’t surprised that the trash ends up in the ocean’s deepest depths because after it drifts into the trenches, there’s nowhere else to go. The trash won’t drift up and out of them and thus collects at the bottom.
Study results are disturbing
According to The Guardian, another researcher who wasn’t even part of the study finds the results “significant and disturbing.” She noted that the Kermadec and Mariana Trenches are miles away from industrial sources. This suggests that even though the chemicals have been regulated for about 50 years, they’re transported long distances by the ocean.
The researchers who conducted the study are now looking at the types of damage the chemicals cause in the creatures they were found in. The crustaceans they studied are extremely hardy, as they’re able to survive water pressure equivalent to a ton on the tip of a finger and temperatures just above freezing. The researchers are also examining the animals for evidence that they have been contaminated by plastic, a hot topic of study among environmental scientists these days.