Levels of radioactive iodine twice the safe level for babies have been detected in tap water in Japan.
The government is advising residents to use bottled water to make up baby milk feeds until further notice. The news prompted a rush on sales of mineral water and many shops have run out.
The government in Tokyo has banned the transport of produce from the vicinity of the Fukushima nuclear plant. At least 11 different types of vegetable have been found to be contaminated.
The US has banned the import of food produce from the Fukusima area. Hong Kong has done the same, the first Asian economy to do so. France has urged the EU to monitor Japanese food imports.
Scientists say the short-term risk is very limited, but questions are being asked about the cumulative, long-term effect.