In the area surrounding the Fukushima Daiichi Nuclear Power Plant there is still something that is not seen. You can't see it, but it remains imprinted on buildings, houses, schools. A radioactive ghost that has the form of tiny radioactive particles, rich in cesium, found in a recent study even in the dust of an abandoned school which is located almost 3 kilometers from the plant.
Radioactive particles, a silent invader
The threat lies not only in the radioactivity, but in the dimensions, which are usually around 5 micrometres or even less.
"Given their size, these radioactive particles could reach the deepest recesses of the lungs, settle there and create problems". To say it is Satoshi Utsunomiya, associate professor at Kyushu University, Japan, and lead author of the study just published in Chemosphere, that I link to you here.
The Fukushima nuclear accident in 2011 released a considerable amount of these radioactive particles, to the point that researchers have found them in the Kanto region (in 2021) and (in 2019) as far away as Tokyo, a good 300 km away. What was missing was a confirmation of the possible presence of these particles also inside the buildings. Good: that is bad. This confirmation has arrived, and it is also too late and not very updated.
Photograph of a disaster
At the entrance to an abandoned school, I was telling you, Utsunomiya and his team found a landscape suspended in time. Six years after the disaster, in 2017, everything remained exactly as it was at the time of the earthquake. The dust that coated the surfaces was like a time capsule, a tangible account of the disaster. But this powder held a disturbing secret.
"We found radioactive cesium microparticles both at the entrance to the school and on the second floor, with the highest concentrations near the door" says Utsunomiya. This finding, made public only today, is relevant as it suggests that these radioactive particles can accumulate and create "hot spots" of radioactivity, even inside buildings.
Radioactive particles: how has the situation evolved in the meantime?
Given the timing of the research (Covid and other delays that have led to the publication of these results only now, 6 years after the survey) Utsunomiya and Professor Gareth Law, of the University of Helsinki in Finland, co-author, are clamoring for further studies to be done.
The precise health impact of these radioactive particles is not yet fully understood, and analyzing their presence in the indoor environments of the radiation-affected areas of Fukushima is crucial.
"I feel it is our duty to conduct rigorous scientific research on the tragic events in Fukushima, discover and disseminate new knowledge that will be important for society and the next generation" declares Utsunomiya.
What's going on now?
every possible, long cleanup effort to allow life to resume its course will require a deep understanding of the forms and extent of contamination in buildings, to ensure the safety of workers and potential occupants. And it seems that there is not too much desire to delve into the matter.
Japan needs to get rid of it too much, in the year in which all the radioactive waters it has kept until now will pour into the Pacific Ocean. A step forward or a further risk? Only time will tell.