原発風評被害 放射能の基準から考え直せ

The Yomiuri Shimbun (Feb. 26, 2013)
Time to overhaul radiation safety criteria
原発風評被害 放射能の基準から考え直せ(2月25日付・読売社説)

The government should make a sweeping review of safety standards for radioactivity. The recent change of administration offers a golden opportunity to do this.

The Consumer Affairs Agency will reinforce efforts to deal with damage caused by radiation rumors since the crisis began at Tokyo Electric Power Co.'s Fukushima No. 1 nuclear power plant. Masako Mori, state minister for consumer affairs, said, "The Democratic Party of Japan-led administration increased consumers' anxieties." She has issued an order to study concrete measures to alleviate these fears.

Agricultural products harvested in Fukushima Prefecture are shipped after they have been confirmed safe to eat, but they do not sell well unless their prices are set lower than other products. Their distribution volume is barely expanding.

Mori hit the nail on the head when she said a reason for this is that consumers harbor "doubts and concerns about the safety standards."

The administration of former Prime Minister Yoshihiko Noda adopted stricter standards for radiation contained in food than those in place overseas. The Radiation Council, a government advisory panel, had warned about possible adverse effects this might cause, but then Health, Labor and Welfare Minister Yoko Komiyama pushed through the new criteria.

This resulted in more food containing radiation that exceeded the restricted levels. Shipments of wild mushrooms were even halted when a check detected a radioactive substance that could only have been caused by past nuclear tests.


Stricter threshold set

The problem is that the Noda government set the yearly radiation exposure of one millisievert as the threshold between safe and dangerous. The one millisievert a year level, which is nothing but a management standard legally set for facilities that handle radioactive substances, was adopted for food safety standards.

The International Commission on Radiological Protection (ICRP) also considers it advisable to set the permissible annual radiation dose at no more than one millisievert. But the difference between the ICRP's position and that of the Noda administration is that the former does not consider it dangerous immediately even if radiation exposure exceeds the threshold.

The international commission believes health effects cannot be detected clearly if the total radiation exposure is held to 100 millisieverts. Thus, the one millisievert a year considered by the ICRP is a ceiling deemed far lower than its safety standard, and comes with the condition that the exposure target can be achieved reasonably.

Some places in the world are exposed to radiation of 10 millisieverts a year that comes from the ground, among other sources. A radiological examination at a hospital exposes the patient to about seven millisieverts.

The one-millisievert threshold also has become a factor delaying the return of nearly 160,000 evacuees from the nuclear crisis to their hometowns.


Gap with international standards

The commission considers that a radiation dose of up to 20 millisieverts a year is permissible when affected areas are in the reconstruction stage, and efforts must be made as much as possible to reduce the annual exposure to less than one millisievert.

Then Environment Minister Goshi Hosono, however, stressed the importance of achieving the decontamination target of one millisievert or less. Unlike the ICRP's thinking that equally emphasizes protecting affected residents' daily lives and decontamination, the DPJ-led government gave too much weight to decontamination efforts.

A mistaken political message also was given by Niigata Gov. Hirohiko Izumida. He condemned the disposal by the prefecture's Kashiwazaki and Sanjo cities of disaster debris from Iwate Prefecture as general waste as a "criminal act."

But radiation levels of debris from Iwate Prefecture are the same as trash collected within Niigata Prefecture. We urge Izumida, the head of a local government, not to exacerbate damage caused by nasty radiation rumors.

(From The Yomiuri Shimbun, Feb. 25, 2013)
(2013年2月25日01時19分  読売新聞)

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