Thousands of tonnes of dead fish wash up in Japan, three months after the country dumped treated radioactive water from Fukushima into the sea

Thousands of tonnes of dead fish have washed up on a beach in northern Japan, sparking speculation that the release of treated radioactive water from the Fukushima nuclear power plant has wreaked havoc on local ecosystems.

The sardines and some mackerel washed up in Hakodate on Japan’s northernmost main island of Hokkaido on Thursday morning, forming an alarmingly thin blanket that covered nearly a kilometer of coastline.

Officials have been unable to find an explanation for the phenomenon, but Takashi Fujioka, a researcher at the Hakodate Fisheries Research Institute, has put forward a number of theories as to why the fish may have died en masse.

He said they may have been exhausted from lack of oxygen while moving in shallow water in a tightly packed school, or perhaps even During their hike, they suddenly encountered cold water and succumbed to shock.

There are several documented cases of similar phenomena in various parts of the Japanese coast.

However, this particular phenomenon occurred just three months after Japanese authorities began dumping treated radioactive water back into the sea – a move that angered neighboring countries such as China and South Korea.

China has since banned Japanese seafood, criticizing the country as “extremely selfish and irresponsible”.The fact that the Global Times, the flagship newspaper of the Chinese Communist Party, is writing this could open a “Pandora’s box” and raise fears “real Godzilla”.

South Korean protesters also tried to enter the Japanese embassy in Seoul with banners reading “The sea is not Japan’s trash.”

The sardines and some mackerel washed up Thursday morning in Hakodate on Japan’s northernmost main island of Hokkaido.

The phenomenon created a disturbingly thin blanket that covered nearly a kilometer of coastline

A closer look at TEPCO’s Fukushima Daiichi nuclear power plant in Okuma

Residents watching the coast in Hakodate say they have never seen anything like it.

Some collected the fish to sell or eat, prompting the city in a notice on its website to ask residents not to eat the fish.

The rotting fish can deplete oxygen levels in the water and harm the marine environment, Fujioka said.

“We don’t know exactly under what conditions these fish washed up, so I don’t recommend eating them,” he concluded.

In March 2011, the Fukushima power plant was destroyed after an earthquake and the subsequent tsunami destroyed the plant’s cooling systems, causing three reactors to melt down.

Now an underwater tunnel is used to drain the radioactive water, which has been treated by the Advanced Liquid Processing System, which uses a process called isotope dilution to make the water less dangerous.

This process involves adding tritium – a less harmful radioactive isotope – to contaminated water, which is then mixed with “clean seawater”, which dilutes the concentration of more harmful substances.

Japanese officials claim the treated water is safe.

But critics say the lack of long-term data makes it impossible to say with certainty that tritium poses no threat to human health or the marine environment.

Greenpeace said the radiological risks had not yet been fully assessed and that the biological effects of tritium were being “ignored”.

Activists take part in a protest against Japan’s release of treated radioactive water from the destroyed Fukushima nuclear power plant in Busan, South Korea

More South Korean protesters take to the streets to complain about the treatment of toxic water

The Fukushima power plant, pictured after its damage, was crippled by an earthquake and tsunami in 2011.

A look at Japan’s Fukushima power plant and its four nuclear reactors. One kilometer away, an underwater pipe will be used to drain away the toxic water