Cesium from the urine of 40% of the children in Iwate, “Considering to stop the research anymore”

Last April, Fukushima Diary reported cesium was measured from the urine of 119 among 132 children in Iwate. [URL 1]

The second survey was conducted from last October to January. The result showed they still measured cesium from the urine of 35 among 86 children.

1 ~ 2 Bq/ 2L (The amount of urine per a day) : 3 children
~1 : 32 children
Not detected : 51 children

The biological half-life of cesium is 70 days at average. Considering that children have shorter half-life than that, they still detect high level of cesium from unexpectedly high rate of the children, but they are considering to stop the research. The reason is “taking 2L of the urine sample is hard for the children.”

In the first test, they measured 1 ~ 2 Bq/2L of cesium from 33 (25%) of the children and 2 ~ 3 Bq/2L of cesium from 25 (18.9%). They comment the result has become better than the first time.

They calculated the integral exposure dose until 70 years old to be 0.01 mSv, but the the coefficient and its basis are not clear. (cf, [Column] What is Sv, Bq, Cesium, how and why it matters [URL 2])






Français :

Du césium dans 40 % des urines des enfants d’Iwate, “On envisage d’arrêter les recherches”


En avril dernier, le Fukushima Diary rapportait que du césium était relevé dans les urines de 119 de 132 enfants d’Iwate. [Lien1]

La deuxième recherche a été menée entre octobre dernier et janvier. Les résultats montrent qu’ils  relèvent toujours du césium dans les urines de 35 des 86 enfants.

1 ~ 2 Bq/ 2L (=quantité d’urine journalière) : 3 enfants
~1 : 32 enfants
Non détecté : 51 enfants

La demie-vie biologique du césium est de 70 jours en moyenne. En considérant que les enfants en ont une plus courte, ils trouvent toujours de hauts niveaux de césium dans une proportion inattendue d’enfants mais ils envisagent d’arrêter les recherches. La “raison” invoquée est que “prendre 2L d’échantillon d’urine est dur pour les enfants”.

Les premiers tests avaient relevé de 1 à 2 Bq/2L de césium pour 33 (25%) des enfants et de 2 à 3 Bq/2L de césium pour 25 (18.9%). Ils disent que les résultats se sont améliorés depuis la première fois.

Ils ont calculé que la dose d’exposition intégrale jusqu’à 70 ans devrait atteindre 0.01 mSv mais le coefficient et ses fondements ne sont pas clairs. (cf. [Édito] Que sont les Sv, Bq, césium, comment et pourquoi s’en soucier [Lien2])


About this site

This website updates the latest news about the Fukushima nuclear plant and also archives the past news from 2011. Because it's always updated and added live, articles, categories and the tags are not necessarily fitted in the latest format.
I am the writer of this website. About page remains in 2014. This is because my memory about 311 was clearer than now, 2023, and I think it can have a historical value. Now I'm living in Romania with 3 cats as an independent data scientist.
Actually, nothing has progressed in the plant since 2011. We still don't even know what is going on inside. They must keep cooling the crippled reactors by water, but additionally groundwater keeps flowing into the reactor buildings from the broken parts. This is why highly contaminated water is always produced more than it can circulate. Tepco is planning to officially discharge this water to the Pacific but Tritium is still remaining in it. They dilute this with seawater so that it is legally safe, but scientifically the same amount of radioactive tritium is contained. They say it is safe to discharge, but none of them have drunk it.


January 2013