Dr. Shunichi Yamashita: I thought, "Oops..." After Seeing the SPEEDI Simulation Map on March 23, 2011

Right after the start of the nuclear accident on March 11, 2011, the Japanese national government, then under the Democratic Party of Japan headed by Naoto Kan, initially said they didn't know about SPEEDI. What was SPEEDI? Then they said SPEEDI failed to work. Then on March 23, 2011, Nuclear Safety Commission reluctantly made several SPEEDI simulation maps available to the public. Full disclosure didn't come until early May, 2011. (WSPEEDI disclosure was even later, in mid May 2011.)

By that time, it was too late for the residents in Fukushima Prefecture and areas in Miyagi Prefecture and northern Kanto, and it was apparently too late for Dr. Shunichi Yamashita, thyroid expert and special advisor to Fukushima Prefecture at that time.

According to Asahi Shinbun's still on-going "Trap of Prometheus", Dr. Yamashita was caught off guard when the SPEEDI simulation maps were finally made public. He had confidently persuaded the officials of Fukushima Medical University in the preceding days that there was absolutely no need to distribute potassium iodide pills because the spread of radioactive materials from the accident, compared to the Chernobyl accident, would be so miniscule.

But the SPEEDI simulation maps showed the areas with 100 millisieverts or more equivalent dose at thyroid (effective dose for the whole body is 100x0.04=4 millisieverts) extended far beyond the 30-kilometer radius evacuation zone.

I guess Dr. Yamashita was basing his assertion on his hope. Or he truly believed there was no SPEEDI simulation. Or he was a medical doctor not nuclear scientist. Or all of the above.

Oops.

From "Trap of Prometheus" on November 7, 2013, on Dr. Yamashita prevailing on potassium iodide pills and speaking about the "fate" of Japan as an earthquake-prone country with many nuclear power plants:

大阪空港経由で山下が福島に入ったのは１８日午後。午後６時からの県立医大の職員向け講演会に登壇した。同僚教授の松田尚樹（５６）、高村昇（たかむらのぼる）（４５）も一緒だった。

Yamashita arrived in Fukushima in the afternoon of [March] 18, via Osaka Airport. He appeared in the lecture for the staff at Fukushima Medical University on the same day at 6PM. He was accompanied by the fellow professors [at Nagasaki University], Naoki Matsuda (age 56) and Noboru Takamura (age 45).

大会議室で行われたこの講演会には３００人の職員が集まった。多くの職員が放射能対策のマスクをつけたまま、話に耳を傾けた。

There were 300 people who attended the lecture held in the large conference room. Many were wearing masks to block radioactive materials.

山下は最後にマイクを握った。

Yamashita spoke last.

話の要点は安定ヨウ素剤が必要か否か。山下はチェルノブイリ事故も例に出し、不要論を展開した。

The talk was about whether potassium iodide pills were necessary. Citing the Chernobyl accident, Yamashita said there was no need:

（１）安定ヨウ素剤で甲状腺がんが防げるという誤解が広がっているが、「ヨウ素剤信仰」にすぎない。日本人が放射性ヨウ素を取り込む率は１５～２５％。４、５割を取り込むベラルーシとはわけがちがう。

(1) Many believe that potassium iodide pills will prevent thyroid cancer, but it is nothing but "iodine religion". For the Japanese, the intake of radioactive iodine would be 15 to 25%, unlike 40 to 50% for people in Belarus.

（２）２０キロ圏、３０キロ圏以西の被曝（ひばく）量はおそらく１ミリシーベルト以下。チェルノブイリと比べて被曝量が微量なので、日本政府も安定ヨウ素剤服用の指示を出さない。

(2) The amount of radiation exposure west of the twenty, thirty kilometer radius [from the plant] will probably be less than 1 millisievert. [Not clear whether he meant effective dose for the whole body or thyroid equivalent dose.] Compared to Chernobyl, the amount of radiation exposure will be so small that the Japanese government will not issue instruction to take potassium iodide pills.

（３）服用マニュアルは数々の欠点がある。使われないことを祈る。

(3) The dosing manual has many defects. I hope it won't be used.

最後、こう職員を鼓舞した。

In conclusion, Yamashita tried to raise the morale of the staff:

「ぜひ逃げ出すことのないように。事故による被曝は地震国で原発立国を進めてきた日本の宿命です」

"I beg that you do not escape [desert your post]. Radiation exposure due to a nuclear accident is a fate of the quake-prone Japan that has nonetheless been promoting nuclear power plants."

Well, his last remark is, sadly, spot on. People in Japan had failed to see it, or refused to see it, until the Fukushima I Nuclear Power Plant accident.

From "Trap of Prometheus" on November 8, 2013, on "Oops...":

討議の結果、骨格を固めていた最寄り薬局利用案を踏襲することにした。（１）最寄りの薬局で安定ヨウ素剤を渡す（２）大人には錠剤、乳幼児には粉末を分包にして渡す（３）苦いので、乳幼児にはジュースに溶かして飲んでもらう。

After discussion, they [Fukushima Medical University staff] decided to adopt the plan they had been fleshing out, which was to use the neighborhood pharmacies. (1) People receive potassium iodide at the neighborhood pharmacies; (2) pills for adults, power for small children; (3) for small children, powder was to be dissolved in juice, since the powder was bitter.

山下の了解が出れば、この案を県に提案する予定だった。県は十分な在庫を持っており、県には服用を指示する権限もある。このときがヨウ素剤が行き渡るチャンスだった。

If Yamashita OKed, this plan was to be suggested to the prefectural government. The Fukushima prefectural government had ample stock [of potassium iodide] and had the authority to instruct people to take it. This was an opportunity to distribute potassium iodide pills to the residents.

しかし同日、山下はこの案を却下した。理由は以下の通り。

However, Yamashita rejected the plan, for the following reasons:

（１）原子力安全委員会のマニュアルから逸脱する（２）服用量を誤る危険もあるし、副作用が出た際に対応が困難（３）飲み物と混ぜた場合に効き目があるかどうかわからない――。

(1) The procedure was not in the manual by the Nuclear Safety Commission; (2) There was a danger that people would take a wrong dosage, and it would be hard to respond to the side effect; (3) there was no knowing if it was effective if mixed with drink.

日本甲状腺学会理事長をつとめる山下の意見は絶対だった。３月１２日以降、医大で話し合われてきた配布案はこれで尻すぼみとなった。

As the president of Japan Thyroid Association, Yamashita's opinion carried weight. The plan to distribute potassium iodide that had been discussed at Fukushima Medical University since March 12 tapered off.

ところが……。

However,

数日後、山下は想像を超えた事実に驚いたと明かす。以下、ことし６月に山下から取材した内容だ。

Yamashita reveals he was surprised by the fact that was beyond his imagination. The following is from our interview with Yamashita in June this year.

山下を驚かせたのは、１１年３月２３日に国が公開したＳＰＥＥＤＩ（放射能拡散予測システム）の計算図だった。当時のヨウ素剤服用基準は、甲状腺の被曝（ひばく）線量が１００ミリシーベルトになると予測されたとき。計算図では１００ミリを超える地域が原発３０キロ圏外にも大きく広がっていた。

What surprised Yamashita was the SPEEDI simulation maps that the national government disclosed on March 23, 2011. At that time, the standard for taking potassium iodide pills was when the equivalent dose at thyroid was expected to reach 100 millisieverts. In the simulation maps, the areas where the equivalent dose would exceed 100 millisieverts extended far outside the 30-kilometer radius from the plant.

「ありゃー、と思いました」

"I thought, 'Oops...'"

放射能汚染は山下の予想を大きく上回っていた。

Radiation contamination far exceeded Yamashita's expectation.

「日本の原発にはヨウ素とかを取り除くフィルターとかがきちんと付いているものだと思っていた。まさかこんなに広範囲に汚染されているとは思わなかった」

"I had thought a nuclear power plant in Japan was properly equipped with filter or something to remove iodine and other nuclides. I never imagined such wide areas were contaminated."

This particular segment of "Trap of Prometheus" reads like a hit piece to put all blame on Dr. Yamashita regarding the debacle over potassium iodide pills that were never distributed.

Distributing potassium iodide pills on March 19, 2011 may have helped somewhat to protect the residents in Fukushima (at least) from the fresh release of radioactive materials from Fukushima I Nuclear Power Plant from March 20 to 23, 2011. But what would have mattered much, much more is if the residents were able to take potassium iodide before the reactors exploded and dry vents were carried out, with the latter apparently releasing much more radioactive materials than the explosions.

And that was all before March 15, 2011, and Dr. Yamashita didn't even arrive in Fukushima until March 18.

Who was responsible for ordering the distribution of the pills? The national government, and the Fukushima prefectural government. Instead of distributing the pills, what did they do? They accused the town of Miharu that distributed the pills and ordered the residents to take them of acting on its own without the government order. They also used the media to educate the viewers on the "danger" of potassium iodide pills, instead of danger of radioactive iodine uptake. (They continue to do this even today, and enough people are so convinced of the danger of potassium iodide pills that they furiously try to refute anyone who touts the benefit of taking them in a nuclear accident.)

Unlike Dr. Yamashita who didn't see the SPEEDI maps until March 23, 2011 like the rest of us, the ministers of the Kan administration, bureaucrats at METI and Ministry of Education, the governor of Fukushima Prefecture and officials at the Fukushima prefectural government, and even the municipal government heads in Futaba, Okuma, and Tomioka in Fukushima had either SPEEDI simulation maps or TEPCO's simulation maps or both from the beginning of the accident. They all sat on the data. Or worse. In case of the Fukushima prefectural government, they deliberately deleted the emails that contained SPEEDI simulation maps.

There is one good thing I would say about Dr. Yamashita. He is honest. As Asahi reports, he readily admitted he had made a potentially grave mistake when he saw the SPEEDI simulation maps. No self-conscious and politically savvy scientist would say things like "Oops..." in an interview for a national paper. When he gave lectures to the residents in Fukushima Prefecture in the populous middle-third Nakadori region starting March 21, 2011, telling them the effect of radiation won't come to people who are smiling, his face and mannerism as he delivered the speech revealed he was at least uncomfortable, probably very worried.

That lecture series started right when there was something happening in Reactor 3 causing the release of a significant amount of radioactive materials, and spikes in radiation were observed in wide areas in Tohoku and Kanto (March 20 - 23, 2013). Dr. Yamashita continued telling the Fukushima residents there was nothing to worry about, after he saw the SPEEDI maps and realized his assumption was very wrong.

Dr. Yamashita has since returned to Nagasaki University, though he still is the special advisor on radiation risk management for Fukushima Prefecture.

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