Radiation poisoning causes acute sickness, as well as DNA mutations that may be passed on to future generations. Because of these damages, there is vast concern on how radioisotopes affect marine fauna.
Bioaccumulation is the process by which harmful contaminants accumulate in organisms at the top of the food chain. Top predators, such as Pacific Bluefin Tuna, are at risk because they consume numerous, small organisms, along with the radioactive particles that the prey have inside their bodies. As tuna eat contaminated prey, the radiation increases in its tissues exponentially.
The long-term effects of radiation on marine fauna are still unknown. However, we do know that even though radioisotopes are diluted by the ocean, fish are concentrating it in their bodies through the process of bioaccumulation.