Traces of nuclear weapons tests at the bottom of the Mariana Trench

Radioactive carbon released into the atmosphere during nuclear weapons tests last century has reached the deepest parts of the ocean, according to a new study. Scientists have found traces of it in the tissues of crustaceans inhabiting ocean trench bottoms.

In the muscle tissues of the crustaceanow inhabiting the deepest areas of the oceanow, including the area around the Mariana Trench – the deepest ocean trench on Earth – found traces of last century’s nuclear weapons tests. New study shows significantly elevated levels of carbon-14 – radiotworic isotope of carbon – u obunogow – small crustaceanow of the armadillo clusterow.

According to the authors of the publication, whichora was published on „Geophysical Research Letters”, radiotworczy isotope of carbon has entered the food chain. It was initially present in the bodies of creatures living on the surface of the oceanoin or shallower waters. But crustaceans inhabiting the ocean floorsow feed on organic matter the organismow living on the surface, whichora sinks to the bottom.

– Although it would take hundreds of years for the ocean circulation to bring the water containing bomb traces to the deepest ocean trench, the food chain achieves this much faster – said Ning Wang, a geochemist at the Chinese Academy of Sciences in Guangzhou, China, and a majorowna author of a new study.

Wang and her colleagues were looking for carbon-14, whichory naturally forms when cosmic rays interact with nitrogen in the godifferent layers of the atmosphere. Scientists can detect it in almost all living organisms. It is used to determine the age of probek archeological and geological.

However, nuclear weapons tests over the past century have significantly increased the presence of this radiotoxinoric isotope in the atmosphere when neutrons released from bombs reacted with nitrogen in the air. In the 1990s. Carbon-14 levels have fallen to 20 percent above pre-test levelsoin, but the latest study shows that it is still present, and in a rather surprising place.

Since the development of nuclear weapons in 1945 until today, nearly 2,500 test explosions have been carried out. The overwhelming majority should be credited to Stanoin the United States and the Soviet Union. But the British, Chinese, French, Indians and Pakistanis have also conducted their tests. In recent years, this group has been joined by the regime of Kim Jong Un.

Radiotworczy carbon coming from the testow nuclear weapons quickly mixed into the ocean surface. Marine organisms have begun to use this carbon in their bodies. Scientists have observed elevated levels of carbon-14 in marine organisms since the nuclear tests began. Now it has been spotted in the tissues of creatures living on the ocean floorow.

– There is a very strong interaction between the surface and the bottom when it comes to biological systems, and human activity can affect biosystems as deep as 11,000 metersoin, so we need to watch out for our future behavior of – related Weidong Sun, a geochemist at the Chinese Academy of Sciences in Qingdao, China, and coothe chain of the new study. – We did not expect this, but it is understandable because it is controlled by the food chain,” he added.

In the new study, the researchers wanted to use carbon-14 as an indicator for organic material in ocean trenches to better understand the organisms living in it. Wang and her colleagues analyzed the obunogs collected in 2017. from the Mariana Trench, the Mussau Trench and the New Britain Trench in the western Pacific Ocean.

Surprisingly, the researchers found that carbon-14 levels in the muscle tissues of amphipodsow are much higher than the carbon-14 levels in organic matter found in deep ocean water. They then analyzed the contents of the crustacean’s gutoin and found that these levels correspond to estimated carbon-14 levels from probek of organic material taken from the surface of the Pacific Ocean.

Interestingly, scientists have found that crustaceans living in these ditches become larger and live longer than their counterparts in shallower waters. Obunogi, whichore live in shallow water, usually live kroc years old and grow to an average length of 20 millimetersow. However, the researchers found amphipods in deep ditches, ktore were more than 10 years old and reached a length of 91 millimetersow.

The authors of the study suspect that the large size and long life span of crustaceansow are likely byproducts of their adaptation to living in an environment of low temperatures, high pressure and limited food supply. They also suspect that the animals have a slow metabolism, allowing them to store energy for long periods of time.

– In addition to the fact that the material comes mainlyown from the surface, age-related bioaccumulation increases roalso these pollutant concentrations, bringing a greater threat to these most remote ecosystems, Wang said.

A new study shows that deep ocean ditches are not isolated from human activity.