Concerns about food safety have spread to Tokyo, and prompted U.S. officials to halt the import of certain foods, as the Japanese government estimated the massive quake and ensuing tsunami could be the world's costliest natural disaster ever.
Officials from the Tokyo Water Bureau said Wednesday that the level of radiation detected in the city's tap water had risen to more than twice the recommended level for infants.
Tests at a downtown Tokyo treatment plant that filters much of the city's tap water showed elevated levels of iodine-131 at a concentration of 210 becquerels per litre.
Because babies are more susceptible to developing thyroid cancer as a result of exposure to radioactive iodine, parents in the Tokyo area are being advised to limit how much tap water they give their infant children.
But, even though the level is more than twice the 100 becquerels per litre experts say is safe for infants to consume, older children and adults are being told they have no reason to fear water from their taps
"Even if you drink this water for one year, it will not affect people's health," Japan's Chief Cabinet Secretary Yukio Edano told reporters.