Decades after the atomic bomb tests from the Cold War, traces of radioactive carbon dioxide were found in the deepest portions of the ocean. Crustaceans found in the deepest trenches of the Pacific Ocean showed elevated levels of radioactive carbon to their muscle cells, based on a study published in the journal Geophysical Research Letters in April. The bomb carbon found its way in their molecules from nuclear tests performed in the 50s and 60s, and it is been found kilometers down to the ocean where these animals live.

The results show how fast human pollution may enter the ocean food chain and also reach the deep ocean, in accordance with the study’s authors. It is a discovery that shows how an actions of humans can damage the planet. We did not expect such high degrees of carbon-14, co author Weidong Sun, a professor of geology in the Chinese Academy of Sciences in Qingdao, China, told CNN. Which means the ocean was polluted by humans activities.

How can the radioactive carbon get in the ocean?. Throughout the atomic tests of the Cold War era, radioactive carbon in the atmosphere has doubled. The neutrons released in the bombs reacted with the nitrogen in the atmosphere, creating radioactive carbon or carbon-14. When the atomic tests stopped, the degree of radioactive carbon went down. Nevertheless, it was already too late. The bomb carbon dropped from the atmosphere to the surface of the ocean. Marine animals have been eating things from the ocean over decades and scientists have seen increased amounts of carbon-14 since the bomb test. Researchers in China and the USA utilized the bomb carbon to follow organic matter in the organisms that live in the deepest portions of the ocean.

They studied crustaceans that live in hadal trenches, which can be located 6, 000 to 11, 000 meters beneath the ocean’s surface. The crustaceans studied came from 3 trenches in the West Pacific Ocean. The conditions in these trenches are harsh, the animals that live there must adapt to extremes higher pressure and lack of nutrients and light. The crustaceans scavenge and depend on dead organisms that fall into the ocean floor for food. When researchers carbon obsolete the crustaceans, they found the levels of carbon-14 within their muscle cells were a lot higher compared to the amounts of carbon found naturally in the deep ocean.

Carbon-14 is found in all living things and can be used to date the relative age of organisms in a process called carbon dating. Carbon has reached the bottom quicker than expected. Typically, it’d take about 1, 000 years for the ocean to circulate the bomb carbon to the deep sea. However, the ocean food chain carried the radioactive carbon quicker than researchers expected.