The Japanese government has ordered farms in four prefectures near the stricken Fukushima nuclear power plant to stop shipping a range of products found to have elevated radiation levels, an official has said.
The affected prefectures are Fukushima, Ibaraki, Tochigi and Gunma, a health ministry official told the AFP news agency on Wednesday.
Naoto Kan, the country's prime minister, has told governors in the affected prefectures to halt shipments of broccoli and "komatsuna" green leafed vegetables from Fukushima, as well as untreated milk and parsley from neighbouring Ibaraki, Japanese media reported.
NHK, the national public broadcaster, said that Kan had told people in those areas not to eat the said vegetables, as they had been found to have abnormal radiation levels due to releases from the Fukushima Daiichi power plant, which was badly damaged by the March 11 earthquake and subsequent tsunami.
Higher than legal levels of radioactivity have been found in 11 different kinds of vegetables grown in Fukushima, including cabbage and some greed leafed vegetables, the health ministry said.
Radioactive caesium was found to be at 82,000 becquerels (164 times the legal limit), and iodine at 15,000 becquerels (more than seven times the limit) in a certain type of leafed vegetable, the ministry said.
Officials in six more prefectures - Miyagi, Yamagata, Niigata, Nagano, Saitama and Chiba - have been asked to step up radiation monitoring on farm products, the official said.
Radiation exceeding health limits for infants has also been found in a Tokyo city water purifier, a local government official said on Wednesday. The government has advised residents throughout the city to avoid using tap water to make infant formula until further notice as a precaution.
"It does seem that radiation contamination in food is spreading. The WHO [World Health Organisation] says it's spread over a wider geographic area than was first thought," Al Jazeera's Andrew Thomas reported from Morioka. He said the 11 vegetables affected include cauliflower, broccoli, cabbage and spinach.
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"The levels of radiation in those foods is low, but many many times the normal level. And it's affecting not just those farmers in that direct area, but the reputational damage it's doing is affecting farmers up and down Japan."
Radiation has also been found in milk, tap water and the Pacific sea, though the government and experts continue to say that levels are far from being dangerous to humans.
It is not clear whether radioactivity could affect seafood, but the local fishing industry has already been ruined by the earthquake and tsunami.
"There are no fish coming from the regions that were hit, so no fish [being sold] are contaminated," Rika Tatsuki of the National Federation of Fisheries Co-operative Associations was quoted by the Reuters as saying.
The government has started to test fish and shellfish, though it remains unclear whether radioactivity has affected them yet.
China, Japan's biggest trading partner, ordered testing of Japanese food imports for radiation contamination and the WHO said Japan will have to do more to reassure the public about food safety.
Several countries, including Malaysia, South Korea, Taiwan and China, have moved to subject imports to radiactivity testing.
The United States is the first country to block certain imports entirely from Japan's radiation-affected zone, halting milk, vegetable and fruit shipments from areas affected by contamination fears. South Korea and Hong Kong both announced on Wednesday that they were considering similar bans.
Meanwhile, two workers at the Fukushima Daiichi complex were injured while working to restore power to the Number One reactor, the Kyodo news agency reported on Wednesday.
This is the same reactor where temperatures rose above safety limits earlier in the day, though the country's nuclear agency said there was no immediate danger.
Workers at Number Two reactor have now temporarily stopped work due to safety concerns.
A low-intensity earthquake jolted the area near the plant on Wednesday, the Associated Press reported, but there were no initial reports of damage. The quake had a magnitude of 4.7 at a depth of 10km, Japan's meteorological agency said.
Earlier, power lines to all six nuclear reactor units were connected, its operator said, but electricity had not been turned on.
The Tokyo Electric Power Co (TEPCO) warned on Tuesday that equipment still had to be checked before power could be properly reconnected, which would mark a significant step in bringing the reactors back under control.
The earthquake and tsunami had damaged the plant's cooling functions, resulting in radiation leaks.
Engineers have, however, been able to cool a spent fuel pool that was nearly boiling, bringing it back to 105 degrees after dumping 18 tonnes of seawater into a holding pool.
Death toll to rise
On Wednesday, the government said the number of people confirmed dead or listed as missing topped 24,000, 12 days after the twin disasters hit.
|The earthquake and tsunami have left some towns completely flattened [GALLO/GETTY]
The National Police Agency put the number of people confirmed to have been killed at 9,408, with a further 14,716 listed as missing, at noon on Wednesday.
A total of 2,746 people have been listed as injured.
The quake and tsunami obliterated towns, which are now wastelands of mud and debris, leaving more than 350,000 people homeless.
On Wednesday, the Japanese government said that it estimated the damage to the country's infrastructure and economy to amount to 16-25 trillion yen ($197-308 billion).
Francis Markus, an official with the Red Cross and Red Crescent Society, told Al Jazeera that getting the required aid to evacuation centres was "very challenging", but that the situation is improving.
Al Jazeera's Thomas, in Morioka, reported that after being criticised in the days immediately after the disaster, the authorities have increased their efficiency in response.
"Japan has a huge infrastructure that sort of kicked in to place for this disaster. I wouldn't quite go as far as saying they were ready for it - how can you be ready for a massive earthqauke, tsunami and then a nuclear crisis as well - but they've certainly ramped everything up," he reported.
"The progress that has been made ... is quite staggering. The very fact that you can drive through [areas where the tsunami hit], the debris cleared to the sides of the road, says a lot any way ... obviously the evacuation centres are up and running, but they have an amazing kind of officialdom that has kicked in and every building that hasn't been knocked down, has been put over to official purposes."
Twenty five embassies, meanwhile, have temporarily shut their operations in Tokyo, Foreign Minister Takeaki Matsumoto said on Wednesday.
Robert Gates, the US defence secretary, has said that he is "very concerned about the health" of US military personnel currently conducting relief work in Japan, referring to fears of high radiation levels causing health concerns.