Observed Environmental Radiation Levels in Mie Prefecture


2011/05/09 Monday Health, News

Observed Environmental Radiation Levels in Mie Prefecture

In Mie Prefecture, Environmental Radiation Levels have been measured and monitored since 1988.
Radiation measurements taken each hour from 0:00 on the 12th of March 2011, can be viewed through the link below.

Observed radiation levels for each month from April 2009 to February 2011 and levels from the 1st to the 11th of March 2011, can be found at the following link.

The current observed radiation levels have no effects on the human body.


Monitoring of Radiation Levels in Mie Prefecture

2011/05/09 Monday Health, News


Information Concerning the Earthquake Centered off the Pacific Coast of the Tohoku Region (Notification No. 8, March 28, 2011)

Concerning the Monitoring of Radiation Levels in Tap Water and Precipitation in Mie Prefecture

As of March 18, 2011, the Mie Prefecture Health and Environment Research Institute has been monitoring tap water in Mie Prefecture daily for signs of radioactive contamination. The Institute has also been monitoring rainwater and atmospheric dust for radioactive particles via samples that are continuously collected 24 hours a day. Because radiation level data take 6 hours to process, observations of radiation levels are conducted once a day.


There have been no harmful non-natural radioactive particles detected in tap water or precipitation in Mie Prefecture. However, there have been a few days when tiny amounts of Iodine-131 were detected in precipitation. The amounts detected have no affects towards the health of Mie residents.

※the term ”non-natural radioactive particles” is defined here as: particles released as a result of nuclear experimentation and/or nuclear energy production, e.g. Iodine-131 and Cesium-137.

Radioactivity monitoring data collected since March 18, 2011 can be viewed at the following website:


The aforementioned website presents data in Japanese. To help you interpret the charts on the aforementioned website, we have translated several important terms below. Please use the translation below as a reference when viewing radiation monitoring data.

(1)水道水の放射能(単位はミリベクレル/キログラム) 毎日午前10時頃更新予定

((1)Radiation levels observed in tap water (measured in units of mBq/kg), updates scheduled for approximately 10AM each day.)

試料採取日 Date(s) of sample(s) セシウム-137Cesium-137 ヨウ素-131Iodine-131
3/27( ) 不検出Not detectable 不検出Not detectable



((2)Radiation levels observed in precipitation (measured in units of M Bq/sq km), updates scheduled for approximately 6PM each day.)


試料採取日 Date(s) of sample(s) セシウム-137Cesium-137 ヨウ素-131Iodine-131
3/27~3/28 検査中Currently processing data 検査中Currently processing data


〔Note〕Japan’s Nuclear Safety Commission has set the following upper limits for radiation in drinking water.

Cesium-137 200 Bq/kg (200,000 m Bq/kg)
Iodine-131  300 Bq/kg (300,000 m Bq/kg)
※In the event that observed radiation levels exceed the above limits, please refrain from consuming the affected water. In these cases, use of tap water for other purposes (e.g. toilet water, etc.) is still safe.