One thing about having a nuclear accident in a rich country is that at least there is going to be good medical care and long-term monitoring. The repair and clean-up operation is another matter, of course — which is why Japan is currently under pressure to accept help from abroad in fixing the appalling mess caused by the three reactor meltdowns at the Fukushima No. 1 nuclear power plant.

But having great monitoring, assessment and medical treatment of citizens is one thing. It is quite another making sure information is communicated to the public clearly and openly. That is something at which neither the plant’s operator, Tokyo Electric Power Co. (Tepco), nor the Japanese government have succeeded at all well. And without good communication, fear and misinformation about radiation can understandably grow.

I was talking about this last week with Gerry Thomas, who runs the Chernobyl Tissue Bank (CTB) at Imperial College London. The CTB collects and analyzes samples of tissue from people exposed to radiation after the Chernobyl nuclear disaster in the USSR (present-day Ukraine) in 1986, and monitors the occurrence of thyroid cancer in contaminated areas.

About Fukushima, she is dismissive of the health risks. That might seem cavalier to people in the Tohoku region of northeastern Honshu who are worried about radiation contamination, but Prof. Thomas has seen what happened in Chernobyl — which released far more radiation than Fukushima has to date.

“Fukushima is nothing compared to Chernobyl,” she told me. “It really is nothing, it’s a tenth of the dose of cesium.” (For the World Nuclear Association report on this, see bit.ly/17urZKd)

The problem in Japan, she says, is more one of communication than public health.

“They’ve got a huge problem out there — largely a PR problem; it’s not a health problem because none of this is going to do anything health-wise,” the professor said.

Our conversation came about because I’d seen a news clip on NHK reporting 18 cases of thyroid cancer in a monitored population around Fukushima.

Fukushima Medical School monitors some 360,000 people who were aged 18 or younger at the time of the March 11, 2011, Great East Japan Earthquake and tsunami. What you might conclude from the report — but you’d be mistaken — is that there is a direct link between the cases of cancer and the release of radioactive material following the meltdown. I asked for Thomas’ opinion.

What we don’t know, she told me, is whether these thyroid cancers are to do with the environment in Fukushima — or whether there is something about the genetics of the people monitored.

We also don’t know, she pointed out, whether the frequency is similar to that seen in other areas of Japan. In Chernobyl (where children were exposed to more than 100 times the maximum dose of radioactive iodine seen after Fukushima), thyroid cancers did not present themselves until four or five years after the disaster.

“Given what we know about radiation dose and time elapsed since the accident,” says Thomas, “I personally cannot see how this finding can be related to the radiation — the doses were too low and the time too short, based on what we know from Chernobyl.”

She directed me to a recent scientific paper reporting the results of radiation monitoring of adults and children around Fukushima. The paper, published in Proceedings of the Japanese Academy, Series B (which you can see for yourself; DOI reference: 10.2183/pjab.89.157), reports on the whole-body radiation screening of nearly 33,000 people.

“Internal exposure levels of residents are much lower than estimated,” write Ryugo Hayano and colleagues of the University of Tokyo.

In the town of Miharu, about 50 km from the stricken power plant, Hayano’s team monitored 95 percent of schoolchildren (aged 6-15). The radioactive cesium in the bodies of all the children was below the detection limit. In other words, they are emphatically not eating food contaminated with radiation.

This sort of nonsensational, reassuring result isn’t something that will generally get reported by NHK or other media outlets.

We are all exposed to radiation, all the time (this fantastic dose chart makes it clear: xkcd.com/radiation) There is, however, a special fear of radiation that is introduced to the environment by human activities. But that fear can get out of hand. Far more radiation was released in the Chernobyl disaster than has been so far from the Fukushima plant, but even the Chernobyl disaster — the world’s worst — can be put into context.

“If you compare Chernobyl with what we allowed to escape into the atmosphere as a result of the nuclear tests in the Nevada desert, that was far, far more than Chernobyl,” Thomas says. “We’ve got a short-term memory about things like this. Instead of looking back and saying, ‘What do we know from exposures in the past?’ we just panic about the next one.”

Her advice: Talk to people.

The Japanese authorities — whether officials from Tepco, the government or monitoring agencies, or academics — ought to be open and learn to communicate better.

As Thomas puts it: “They have got to talk to the local population, they have got to talk to the fishermen, and they’ve got to make people understand that low levels of radiation don’t matter because we’re all exposed to it all the time.”