Higher than safe levels of radiation found in Tokyo water supply

Authorities in Japan have advised residents not to let babies below one  year drink tap water or powdered milk diluted with it after they detected it contained iodine exceeding official levels of radioactivity for infants.

The warning has been sounded to residents in 23 wards and five cities following detection of higher than official levels of radioactive iodine at a water purification plant in Katsushika Ward, Tokyo. 

The news immediately triggered a rush for mineral water at supermarkets and prompted the Tokyo Metropolitan Government to announce that it would distribute a total of 240,000 550-milliliter bottles of water to Tokyo households with infants.

The water taken from the Kanamachi Purification Plant on Tuesday was found to contain iodine-131 with the level of of 210 becquerels per litre of water which is more than double that of the 100 becquerels stipulated for infants in the Food Sanitation Act, according to Ei Yoshida, manage of Tokyo's Waterworks Bureau. 

"The level is not dangerous unless you keep drinking the water for a long period of time," Yoshida told a news conference. "If there is nothing else to drink, you can let babies drink the water every once in a while."

Water from the plant is supplied to the capital's 23 wards as also the suburbs of Musashino, Mitaka, Machida, Tama and Inagi in western Tokyo.