Contamination level is increasing in Tokyo Bay

Contamination level is increasing in Tokyo Bay

Following up this article..Tama river fish contaminated

Cesium is carried from the rivers to Tokyo Bay.

Prof. Yamazaki from Kinki university measured cesium contained sea ground soil at 36 points of Tokyo bay.  The result shows the contamination level is increasing near the outlet of Arakawa river. He assumes cesium is carried from contaminated river.


(5 cm deep in the sea ground, cesium 134 and 137)

8/2011 : 308 Bq/Kg

10/2011 : 476 Bq/Kg(↑155%)

12/2011 : 511 Bq/Kg(↑107%)


It’s in the increasing trend at many other points too. Cesium level is higher near the river than the center of Tokyo Bay.

He also measured how deep cesium 134 is contained in the sea ground at 4 points near a river. As the result, cesium was measured already 24~26 cm deep underground. Usually, mud is deposited 1~2cm yearly near the outlet of a river. Prof. Yamazaki assumes cesium may have been carried by benthic organism.




原発事故由来セシウム濃度 東京湾じわり上昇

2012年3月2日 07時04分
山崎教授は昨年八月以降、湾内の三十六カ所で海底の泥に含まれる放射性セシウム134と137の濃度(一キログラム当たり)を測定している。 福島第一原発事故による影響で、東京湾の荒川河口付近の海底で放射性セシウムの濃度が上昇していることが近畿大の山崎秀夫教授(環境解析学)の調査で分かった。国は現時点で東京湾で調査を行っておらず、山崎教授は「今まさに原発事故由来の放射性物質が、首都圏の放射能濃度の高い地域を流れる河川から東京湾に届いたところ。今後の推移を見守るため、国による継続的な調査が必要だ」と指摘する。






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.


March 2012