Experts have cast doubt on a report that north-eastern Japan’s Hiroshima-Kobe region – home to two nuclear power plants, an international airport and nuclear power plants – is suffering from a wildlife crisis because of radioactive fallout from the 2011 tsunami.
The Fukushima Daini and Hamaoka nuclear power plants about 120km (75 miles) from the quake-hit Japanese coast led to the world’s worst nuclear crisis since Chernobyl. The tsunami flooded cooling systems at the Fukushima Daiichi plant, causing meltdowns in three of its reactors.
The Fukushima prefectural government on Wednesday held a news conference to announce a wildlife crisis in the Fukushima prefecture region and by extension the Fukushima region in general. It said an electronic tag survey had revealed that some animals were dying of radiation poisoning in the Kanto region around Tokyo that includes Fukushima and used to be the world’s busiest airport.
Vicky William (@Vicky_Wills) More than a dozen buses carrying people from the local schools and from Fukushima Prefecture have arrived here for a “tourist” for a news conference on the issue of radiation affecting wildlife. Great bus loads of young people gathering pic.twitter.com/tgyyIwDt3r
The centre of Fukushima was the site of the world’s worst nuclear crisis since Chernobyl in 1986. Photograph: Yuya Shino/Reuters
“There is no doubt that toxic exposure caused a large-scale decrease in the population of natural defence species, but it is unclear how much of that decrease is due to [nuclear] accidents and how much to natural factors,” said Yoshinori Nagahama, a lead author of the assessment. “We need to conduct and confirm experiments on the spread of invisible particles and on these non-visible [fibers] for a long period of time, but we cannot predict with any certainty how many animals died in Fukushima.”
He said there was no solid data on the effects of radioactivity from Fukushima.
Hiroshima-Kobe prefecture officials said they had conducted a survey of the region between September and December last year and found that contaminated soil near the three nuclear power plants was found in a sample of 9,200 hectares, or more than 8,500 acres.
Concentrations of radioactive iodine-131 exceeded legal limits at one point of 20% in the Shimadzu forest, to the north of Tokyo, and drinking water samples showed traces of radioactive cesium-137 were found in a general area. More than 900 amphibians and 500 mammals had died in a week before the survey began, the survey found.
The Fukushima prefectural government has advised the people of Fukushima to avoid contact with contaminated soil and to limit their food intake.
But the region is also home to wildlife, including seabirds, deer, shaggy pigs, black bears, abalone, seaweed and Japanese skunk, and global animal and plant researchers have said the findings are surprising.
A photograph taken from above shows a flock of snow-white, resident snow geese on 5 January near Minamisoma town, located not far from the Fukushima Daiichi nuclear power plant. Photograph: Shoji Naito/AFP/Getty Images
Divers from Japan’s fishery ministry have completed a survey of more than 70,000 fish captured from 10,000 kilometres (6,500 miles) of coastline and found that just 0.04% were contaminated with radiation.
The prefectural government and the Fukushima Nuclear Institute, an affiliate of the prefectural government, had previously asserted that radiation levels inside the nuclear plant had “completely evaporated” in recent years.
The nuclear industry disputed the prefectural government’s assertion, saying it was unable to confirm that radiation levels had fallen.
“It is difficult to determine how the levels have changed, but they do have been going down steadily. And after the last Fukushima nuclear accident they showed we were right,” Katsunori Iwasaki, president of the Fukushima Nuclear Institute, told the Associated Press.
Mikio Nishiyama, a member of the prefectural assembly, said the announcement was a result of government pressure.
“Apparently, the contaminated soil has led to contamination of a wide area,” Nishiyama said. “We must find out what is causing this, and if that is the nuclear plant, we must do all we can to take measures.”