Sources: FDA, Reuters, World Nuclear Association
Another nuclear safety official acknowledged Sunday that the government only belatedly realized the need to give potassium iodide to those living within 12 miles (20 kilometers) of the nuclear complex.
The pills help reduce the chances of thyroid cancer, one of the diseases that may develop from radiation exposure, by preventing the body from absorbing radioactive iodine. The official, Kazuma Yokota, said the explosion that occurred while venting the plant's Unit 3 reactor last Sunday should have triggered the distribution. But the order only came three days later.
"We should have made this decision and announced it sooner," Yokota told reporters at the emergency command center in the city of Fukushima. "It is true that we had not foreseen a disaster of these proportions. We had not practiced or trained for something this bad. We must admit that we were not fully prepared."
Contamination of food and water compounds the government's difficulties, heightening the broader public's sense of dread about safety. Consumers in markets snapped up bottled water, shunned spinach from Ibaraki — the prefecture where the tainted spinach was found — and overall express concern about food safety.
Experts have said the amounts of iodine detected in milk, spinach and water pose no discernible risks to public health unless consumed in enormous quantities over a long period of time. Iodine breaks down quickly, after eight days, minimizing its harmfulness, unlike some other radioactive elements which remain in the environment for decades.
The governor of Fukushima, where milk contaminated with iodine was found at one farm Friday, urged dairy farmers across the prefecture to halt all sales — just short of a ban in consensus-driven, if polite, Japan.
Edano, the government spokesman, tried to reassure the public for a second day running Sunday. "If you eat it once, or twice or even for several days, it's not just that it's not an immediate threat to health, it's that even in the future it is not a risk," Edano said. "Experts say there is no threat to human health."
No contamination has been reported in Japan's main food export — seafood — worth about $3.3 billion a year, less than 0.5 percent of its total exports.
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Also worrisome were the traces of radioactive iodine detected in tap water in Tokyo, 220 kilometres from the overheating nuclear plant in Fukushima prefecture, and in several other prefectures, although again the government played down any safety concern.
The iodine in Fukushima tap water tested above safety limits on Thursday, the government said, but had fallen to within legal limits by Saturday.
The food and water reports were the first since the March 11 quake and tsunami knocked out power to cooling systems at the Fukushima Daiichi nuclear complex. Four of the plant's six reactor units have experienced fires, explosions or partial meltdowns.
The contaminated milk was found on farms 30 kilometres from the plant, and the spinach was collected between 80 and 100 kilometres to the south, Edano said.
The government has banned sales and exports of food from the areas where the tainted food was found.
In another development, spinach and milk from farms near the stricken nuclear plant show radiation above the safety limit, and some tap water is showing traces of radioactive iodine, an official said Saturday.
Yukio Edano, the chief cabinet secretary, said more foods will be checked, but what has been discovered so far poses no immediate health risk. He said a person would have to drink the milk for a year to ingest as much radiation as in a CT scan. A year of the spinach would amount to about one-fifth of a CT scan.
"It's not like if you ate it right away you would be harmed," Edano told reporters in Tokyo as Japan's nuclear crisis entered its second week. "It would not be good to continue to eat it for some time."
