The government is considering restricting shipments of spinach and milk from certain areas near the quake-damaged Fukushima No. 1 nuclear power plant because radiation stronger than permissible standards has been detected in those products.
Radioactive substances exceeding national standards have been detected in samples of spinach from Ibaraki Prefecture and of raw milk from Fukushima Prefecture, the government said late Saturday.
If shipments of spinach from Ibaraki Prefecture are restricted, it could affect consumers in the Tokyo metropolitan area because the prefecture's spinach makes up about 30 percent of all spinach sold in Tokyo's major markets, The Daily Yomiuri reports.
The contamination also spread to other vegetables - canola and chrysanthemum greens. Tokyo's tap water, where iodine turned up Friday, now has caesium as well. Rain and dust are also tainted.
In the province of Ibaraki, a centre of vegetable production, tests found radioactive iodine levels in spinach that were 27 times the accepted limit.
Milk in Fukushima was found to be contaminated with radiation 17 times that limit.
The Japanese government said the levels were still far below anything that would cause harm to human health.
Mr Edano said: "Even if you eat and drink them several times it will not be a health hazard. So I would like you to act calmly without reacting."
But a World Health Organisation official said the situation was "more serious" than originally thought, according to Telegraph.co.uk.