What is a reasonably cautious approach to Tokyo tap water?

What do you think a reasonably cautious approach to Tokyo tap water is? 

The level of radiation in 1 liter is apparently equivalent to 1/26th of a chest x-ray. 

Since I drink 2 liters of water a day it seems reasonable to not drink Tokyo tap water. I drink bottled water anyway, so that doesn’t matter. 

But what about other uses of tap water: washing dishes, brushing teeth, showering, boiling eggs (not that there are any eggs to boil). I can’t substitute bottled water for those because bottled water is in short supply and I need to reserve it for drinking. What are other peoples’ thoughts?

doug


Comments

What is a reasonably cautious approach to Tokyo tap water? — 11 Comments

  1. The bottled water I use is Suntory and supposedly is natural mineral water from the southern alps. Anyway, I don’t get the bottled tap water kind like Dasani which they sell in the U.S.I don’t believe I happen to know anybody with a Geiger counter. :)doug

  2. I’m sure all the University of Tokyo has to do right now is drop everything and run tests for me. :)But I can call them and ask if they have already run such tests.Thanks,doug

  3. I am not sure if it’s still safe of boiling those tap water but substitude is necessary but for how long? One suggestion is to radiation water filter if any

  4. Doug. I do not know. Just be as safe as you can. What do your friends in Tokyo say? What about the science community. Better still come home Love, Muttle

  5. Water filters can help, but do not run hot water thru an activated carbon filter, only cold water. Hot water can release trapped contaminants into the water stream. And, to filter out the particles which are radioactive, you need a filter that can filter down to 1/2 or 1 micron, which means a good ceramic filter such as a Big Berkey (around $300) or a Monolithic Filter (around $60). You can google either. In disaster situations, it is better to have gravity filters like these, as municipal water systems tend to get shut down in disasters. These are the types of water filters that the Red Cross and big government tend to take with them for disaster use.

  6. Boiling tap water will do nothing to solve radioactive particles in the water. And, as far as special water filters for radiation, there is no such thing. Filters for water can do a great job of filtering particles in the water, which can be radioactive. And, there are ceramic filters capable of .1 micron. But, radio-nucleotides can be as small as single atoms, and no filter will block that. What has not been reported in Tokyo is the variation of radiation readings in different parts of the city and water system. What I believe has been reported is the highest reading found, not the average or lowest.

  7. I just checked some research (googled) from the late 1950’s and early 1960’s which shows that much data was collected from the Tokyo water supply back then because Soviet Nuclear testing dropped large amounts of radioactive cesium and iodine on Japan. The increased radioactivity of the water in 1957 was thousands of times greater than the current readings in the Tokyo water supply. Having lived there at the time, I do not recall any warnings about water and radiation. So, the Japanese Authorities have more data and long term test results regarding water and radiation than any country on earth.

  8. I am reading your post with a great deal of interest. I live in tokyo,too, getting ready to come back on Friday from the uk. I just saw a report on the BBC news on this topic, saying that the uk’s intake limit on radioactive iodine in the water was 500 becquerels. That’s 5 times higher than Japan’s intake limit. I would like to know what the us’ intake limit is, but I am having a hard time finding this information.

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