Japan radiation fears prompt Maf food watch

Concerns about radioactive contamination of Japanese food by the damaged Fukushima nuclear power plant is being monitored by the Ministry of Agriculture and Forestry.

Milk shipments from Fukushima province have been banned, while those of spinach have been halted from four provinces surrounding the plant.

Japan's chief cabinet secretary Yukio Edano said eating and drinking the products several times would not present a health hazard, although the World Health Organisation said the problem was more serious than previously thought.

MAF spokesman David Crowe said the ministry was monitoring the situation and was in touch with counterparts in Japan.

"We don't actually import a lot of food products from Japan ... and most of what we bring in are specialty products that are processed, things like soy sauce, noodles, wasabi."

MAF had been told Japan had shut down export markets for products from the affected area.

"At this stage we've not detected any issues but our monitoring is literally daily," Crowe said.

"Our bottom line is that we're not going to let anything nasty come in, which is the case for any products of any country."

According to Statistics New Zealand imports last year from Japan included $4.2 million of fish, crustaceans and molluscs, $1.5 million worth of preparations of cereals, flour, starch, milk and pastrycooks' products, and $529,504 of vegetables.

Japan's health ministry has advised against eating leafy vegetables, broccoli and cauliflower produced near the nuclear plant.

People eating vegetables from Fukushima for the past 10 days would have ingested half of the natural level of a year's worth of radiation, the Japanese ministry said.