Japan's radiation food scare is rippling around the world as the United States blocked imports of dairy and other produce from around a disaster-struck nuclear power plant.
Tokyo Water Bureau officials say levels of radioactive iodine in some city tap water is two times the recommended limit for infants.
The officials told reporters that a water treatment centre in downtown Tokyo that supplies much of the city's tap water found that some water contained 210 becquerels per litre of iodine 131.
They said the limit for consumption of iodine 131 for infants is 100 becquerels per litre.
They recommended that babies not be given tap water, although they said the water is not an immediate health risk for adults.
Japan has ordered the halt of consumption and shipments of a range of farm products grown near the quake and tsunami-hit facility after health ministry tests found vastly elevated levels of iodine and caesium.
The United States restricted dairy and vegetable imports from several prefectures, and France called on the European Union to do the same, while Japan was also testing seawater to measure the impact on marine life.
Prime Minister Naoto Kan ordered a stop of shipments of untreated milk and vegetables including broccoli, cabbage and parsley from areas near the Pacific coast plant, 250km northeast of Tokyo.
The health ministry said radioactivity drastically exceeding legal limits had been found in 11 kinds of vegetable grown in Fukushima prefecture.
Radioactive caesium at 82,000 becquerels - 164 times the legal limit - was detected in one type of leaf vegetable, along with 15,000 becquerels of radioactive iodine, more than seven times the limit.
The ministry said that if people eat 100 grams a day of the vegetable for about 10 days, they would ingest half the amount of radiation typically received from the natural environment in a year.
Even if the short-term risk is limited for now, scientists pointing to the 1986 Chernobyl disaster warn that some radioactive particles concentrate as they travel up the food chain and stay in the environment for decades.
The US Food and Drug Administration said it had placed an import alert on all milk, dairy products, fresh vegetables and fruits from Fukushima prefecture and the nearby regions of Ibaraki, Tochigi and Gunma.
"In addition, FDA will continue to flag all entries from Japan in order to determine whether they originated from the affected area," it said. "FDA will test all food and feed shipments from the affected area."
France urged the European Commission to impose "systematic controls for all fresh produce reaching Europe's borders" from Japan, while stressing that it was not calling for a total embargo on Japanese food products "at this stage".
Around Asia, many Japanese restaurants and shops are reporting a decline in business and governments have stepped up radiation checks on the country's goods. Tainted fava beans from Japan have already cropped up in Taiwan.
Japan - a highly industrialised and mostly mountainous island nation - is a net food importer. According to the European Commission, the EU imported 9,000 tonnes of fruits and vegetables from Japan in 2010.
In Japan, any further food shortages threaten to compound the misery for hundreds of thousands made homeless by the 9.0-magnitude quake on March 11 and the jet-speed tsunami it spawned.
Japan's police agency says more than 9,300 people are dead after an earthquake and tsunami. Almost 13,800 are missing.
Those tallies are likely to overlap, but police officials estimate that the final figure will likely exceed 18,000 deaths.
A police spokesman from one of the of the hardest-hit prefectures, Miyagi, estimates that the deaths will top 15,000 in that region alone. Police in other devastated areas declined to estimate eventual tolls, but said the confirmed deaths in their areas already number nearly 3,700.
The National Police Agency said the overall number of bodies collected so far stood at 9,301, while 13,786 people have been listed as missing.
- AFP, AP