Pacific Ocean radiation levels returning to normal after Fukushima disaster: study

A new international research has found out that radiation levels across the Pacific Ocean are quickly returning to normal five years after the Fukushima disaster.

A review by the Scientific Committee on Oceanic Research, which brought together some of the world's foremost ocean experts, found radiation levels off the east coast of Japan were fast returning to normal after being tens of millions of times higher than usual following the disaster.

Following a massive earthquake and ensuing tsunami, in March 2011, three of the Fukushima nuclear plant's reactors were disabled, causing a nuclear accident which triggered one of the largest ever disposals of nuclear material into the world's oceans. Radioactive elements were carried back into the Pacific, with the ocean's currents dispersing it across a huge area.

After analyzing data from 20 studies of radioactivity related to the Fukushima accident, the report's co-author, Western Australian environmental academic, Pere Masque, said the levels were reducing rapidly from Japan's coast across the Pacific.

"Oceanic currents have dispersed and diluted the radioactive material across the Pacific Ocean as far away as North America," Masque, a Professor in Environmental Radio­chemistry from Edith Cowan University, told NewsCorp on Tuesday.

"Radiation levels across the ocean are likely to return to levels associated with background nuclear weapon testing over the next four to five years."

"As an example, in 2011 about half of fish samples in coastal waters off Fukushima contained unsafe levels of radioactive material however by 2015 that number had dropped to less than one percent above the limit."

However, Masque said the analysis showed that radioactive materials were still leaking from the nuclear plant on Japan's east coast, resulting in the contamination of offshore coastal waters.

"The seafloor and harbour near the Fukushima plant are still highly contaminated and monitoring of radioactivity levels and sea life in that area must continue," he said on Tuesday.

The team of international scientists measured ocean levels of the radioactive chemical element, caesium, an offshoot of nuclear power that is highly dissolvable in water.

Masque said it was a major concern that funds were running out for ongoing monitoring of radioactive material from Fukushima. Endit