Wednesday, March 23, 2011

Radioactive Drinking Water

I imagine politicians will be having even more second thoughts about approving nuclear power plants, after these guys had to go on TV and explain that the water supply of the capital of the country is now radioactive and babies shouldn't drink it:
TOKYO — Radioactive iodine detected in the capital’s water supply spurred a warning for infants on Wednesday as the government issued a stark new estimate about the costs of rebuilding from the earthquake and tsunami that slammed into the northeast of the country this month.

Ei Yoshida, head of water purification for the Tokyo water department, said at a televised news conference that infants in Tokyo and surrounding areas should not drink tap water. He said iodine-131 had been detected in water samples at a level of 210 becquerels per liter. The recommended limit for infants is 100 becquerels per liter.

For adults, the recommended limit is 300 becquerels.

The Health Ministry said in a statement that it was unlikely that there would be negative consequences to infants who did drink the water, but said it should be avoided if possible and that it should not be used to make infant formula.

The warning applies to the 23 wards of Tokyo, as well as the towns of Mitaka, Tama, Musashino, Machida and Inagi to the west of the city.
It probably is true that the health risks are not that great, but the optics are terrible.

The good thing is that Iodine 131 has a half life of only eight days, so when the authorities can bring the reactor under control, the iodine should go away pretty quickly.

1 comment:

Lars-Eric Bjerke said...

I guess it is a bit early to analyze the sequence of events but it is difficult not to.

It seems that the major cause of radioactive releases at present are the spent fuel pits in unit 3 and 4. The loss of power occurred 15.42 March 11, 2011. The first reported fuel pool temperature increase was 84 C in unit 4 at 04:08 March 14, 2011. Then it would take a considerable time, much longer that it took to increase the temperature from 25 C to 84 C, to boil off the 8-10 m of water above the fuel elements. To me this indicates that the fuel pits were damaged or lost water at the earth quake. It would be still worse if the same thing had happened to the major separate spent fuel storage at Fukushima, which contains about ten times as much fuel as the plants.