Radioactive carbon released into the atmosphere from nuclear bomb tests has reached the deepest parts of the ocean, a study has revealed.
Researchers found the first evidence of radioactive carbon from nuclear bomb testing in muscle tissues of crustaceans that inhabit Earth’s ocean trenches, including the Mariana Trench, home to the deepest spot in the ocean.
Organisms at the ocean surface have incorporated “bomb carbon” into the molecules that make up their bodies since the late 1950s, the discovered.
The new study, published in the journal Geophysical Research Letters, found crustaceans in deep ocean trenches are feeding on organic matter from the organisms when it falls to the ocean floor.
The findings show human pollution can quickly enter the food web and make its way to the deep ocean, according to the study’s authors.
“Although the oceanic circulation takes hundreds of years to bring water containing bomb carbon to the deepest trench, the food chain achieves this much faster,” said lead author Dr Ning Wang, a geochemist at the Chinese Academy of Sciences.
Co-author Dr Weidong Sun said: “There’s a very strong interaction between the surface and the bottom, in terms of biologic systems, and human activities can affect the biosystems even down to 11,000 metres, so we need to be careful about our future behaviours.
“It’s not expected, but it’s understandable, because it’s controlled by the food chain.”
The research team said their results also help scientists better understand how creatures have adapted to living in the nutrient-poor environment of the deep ocean.