Radioactive carbon released into the atmosphere from 20 th -century nuclear bomb tests has reached the deepest parts of the ocean, new research finds. A new study in AGU's journal Geophysical Research Letters finds the first evidence of radioactive carbon from nuclear bomb tests 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 this "bomb carbon " into the molecules that make up their bodies since the late s. The new study finds crustaceans in deep ocean trenches are feeding on organic matter from these organisms when it falls to the ocean floor. The results show human pollution can quickly enter the food web and make its way to the deep ocean, according to the study's authors.
How Carbon-14 Dating Works
Carbon dating - RationalWiki
During and after the tests, levels of the radioactive isotope carbon spiked in the atmosphere and in our bodies. And now, researchers have used that to carbon date our immune cells, helping solve a mystery about how our immune systems age. Unsurprisingly, the effects of the atom bomb tests in the s and 60s were felt all across the planet. The blasts doubled the amount of carbon isotopes in the atmosphere, which were taken up by plants from the air. In turn that found its way into animals that eat plants — including humans. One strange side effect of the phenomenon is that it allows scientists to carbon date recent biological samples.
How old atom bomb tests help scientists carbon date our immune systems
Radiocarbon dating also referred to as carbon dating or carbon dating is a method for determining the age of an object containing organic material by using the properties of radiocarbon , a radioactive isotope of carbon. The method was developed in the late s at the University of Chicago by Willard Libby , who received the Nobel Prize in Chemistry for his work in It is based on the fact that radiocarbon 14 C is constantly being created in the atmosphere by the interaction of cosmic rays with atmospheric nitrogen. The resulting 14 C combines with atmospheric oxygen to form radioactive carbon dioxide , which is incorporated into plants by photosynthesis ; animals then acquire 14 C by eating the plants.
When mushroom clouds exploded in the sky during Cold War-era nuclear bombs testing, they also created an unexpected boon for science. The nuclear explosions caused a massive uptick in Carbon that eventually settled in all living tissue—everything from tree rings to elephant tusks to human brain cells. As such, this spike in Carbon has helped scientists date trees, find ivory poachers, and upend a decades-old dogma that new brain cells cannot be regenerated in the human brain. The catch is that the Carbon released before the aboveground nuclear testing ban in is slowly fading to background levels. There's plenty of research yet to be done—but they only have until