Speed Reads

Under the sea

Researchers discover 'extraordinary' levels of toxic pollutants in the deep sea

Scientists exploring the deepest part of the ocean discovered extremely high levels of a toxic pollutant that was banned in the late 1970s because of its harmful effect on the environment.

A robotic submarine dispatched to the Mariana trench in the Pacific Ocean found in the pitch black water tiny crustaceans that were contaminated with 50 times more toxic chemicals than crabs that live in very polluted rivers in China, The Guardian reports. "We still think of the deep ocean as being this remote and pristine realm, safe from human impact, but our research shows that, sadly, this could not be further from the truth," said Alan Jamieson of Newcastle University, who led the research. "The fact that we found such extraordinary levels of these pollutants really brings home the long-term, devastating impact that mankind is having on the planet."

In an article for the journal Nature Ecology and Evolution, Jamieson's team explains that the industrial chemicals, known as persistent organic pollutants (POPs), can interfere with reproduction; they accumulate in fat and are water-repellent, so they are found at the top of the food chain and stick to plastic waste. While it surprised scientists that POPs were found in the most inaccessible place on Earth, Katherine Dafforn, a marine ecologist at the University of New South Wales, pointed out to The Guardian we "still know more about the surface of the moon than that of the ocean floor," and the research by Jamieson and his team "has provided clear evidence that the deep ocean, rather than being remote, is highly connected to surface waters. Their findings are crucial for future monitoring and management of these unique environments."