As of April 4th, their values are better than WHO guidance level under bad condition, and worse than WHO guideline for desired condition.
Radioactive materials in tap water was detected 3/16, near place to the Fukushima nuclear plant.
(earthquake 3/11, the first explosion of reactorNo1 was 3/12, reactorNo3 explosion was 3/14, explosion of reactorNo2 and reactorNo4 was 3/15)
So, purification plant in Tokyo started reporting radioactive material revel 3/17.
According to this pdf document;
(page 203), WHO guidance level are:
According to this page by purification plant in Tokyo;
WHO has another much strict guidance level;
The purification plant says they had been keeping good level last 20 years before 3/17 also.
Current Japanese guicance level which was issued 3/17 are 30time higher than WHO's value:
As Japanese have new guideline, almost all water is SAFE in Japan, Japanese government don't have to notice how much water is contaminated.
Japanese had the same guidance level as WHO before, maybe.
|WHO Guidance level||10Bq/litre||10Bq/litre||10Bq/litre|
|WHO Guideline for water to drink||whole sum of radioactivity |
beta radioactivity 1Bq/litre