Major Japanese food and candy maker Meiji Co. said it was recalling 400,000 cans of powdered milk for infants after traces of radiation from Japan's hobbled nuclear plant were detected in the formula.
The company said it did not know how many of the cans had reached consumers, but acknowledged Wednesday that it was being deluged with queries from worried buyers. The problem milk was manufactured in March and April, and was shipped starting in July with an October 2012 expiration date, it said.
The levels of radioactive cesium detected Tuesday were well below government-set safety limits, and the company said the amounts were low enough not to have any effect on babies' health even if they drank the formula every day.
"We are exchanging it so that people can feel their infants are safe," Meiji said in a statement.
Experts say children are more at risk than are adults of getting cancer and other illnesses from radiation exposure.
"There is no problem because the levels are within the government limit," Kazuhiko Tsurumi, a Health Ministry official in charge of food safety, said of the radiation in Meiji milk.
The March 11 earthquake and tsunami in northeastern Japan sent three reactors into meltdown at the Fukushima Dai-ichi nuclear power plant, and they have been spewing radiation into the air and ocean.
Some of that radiation has crept into food such as rice, fish and beef. But this was the first time radiation was reported in baby formula.
Airborne radioactive cesium contaminated milk as it was being dried at a plant in Saitama prefecture in March, according to Meiji, which has the top market share in Japan in baby formula sales.
It also exports baby milk to Vietnam under a different name, but none of the problem milk was exported to that country, company spokesman Masanobu Nakamura said.
The milk used to make the formula was mostly imported, from Australia and elsewhere. But a small portion of milk from Japan was also used, all from northern Hokkaido farms, which are outside areas that are at radiation contamination risk.
The levels of cesium-134 and cesium-137 in the milk were up to 31 becquerels per kilogram, which is below the government limit of 200 becquerels per kilogram set for milk.
The government has been reviewing its food safety and other radiation standards because some of them were not clearly defined before the nuclear crisis.
Not all food samples are monitored for radiation, and readings have been voluntarily reported by the manufacturers, including the latest by Tokyo-based Meiji.
Many consumers are worried. Some stores are labeling where food was grown or caught, allowing shoppers to opt for imports or products from parts of the country deemed safe.
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