The health ministry has issued to municipalities unified radiation testing guidelines effectively requiring regular sample checks on any food item that has a cesium reading of 50 becquerels per kilogram in current or past random inspections.
The nonbinding guidelines take effect next month and cover any food items subject to the random tests through this month that hit or top the cesium limit.
To date there have been no unified guidelines for radiation tests on food products except for those that have exceeded the current cesium ceiling of 500 becquerels per kilogram. Municipalities carried out their own checks on the food items they suspected may be radioactive.
The ministry’s guidelines, released Monday, will cover municipalities in 17 prefectures in eastern Japan starting April 1, the date a new regulation on radioactive cesium will be enforced that lowers the threshold on food from the current 500 becquerels to 100 becquerels per kilogram.
The guidelines call for more frequent tests on food items from which contamination of 100 becquerels per kilogram has been found until April. These include peaches, shiitake grown on logs, beef, rice and tea.
If sample tests of any of these products detect cesium of 50 becquerels per kilogram in Fukushima, Miyagi, Ibaraki, Tochigi, Gunma and Chiba, followup tests at least three times a week will be required until the end of the harvest season, the guidelines say.
Such followup tests will be required at least once a week in Aomori, Iwate, Akita, Yamagata, Saitama, Tokyo, Kanagawa, Niigata, Yamanashi, Nagano and Shizuoka prefectures. The remaining 30 prefectures will not be subject to the guidelines.
For potatoes, apples, “nashi” pears, sweet potatoes and other items from which contamination levels of 50 to 100 becquerels per kilogram are detected in previous samplings, followup tests must be conducted once a week.
“We have shown details (of which produce to test) to help municipalities prepare sampling test plans,” health ministry official Daisuke Takeuchi told The Japan Times on Tuesday.
“(Each municipality) needs to screen food products to prevent items contaminated more than the threshold from being distributed” to consumers, he said.
Under the new radioactive cesium regulation to be introduced in April, the ceiling for milk will be lowered from the current 200 becquerels per kilogram to 50 becquerels and for water from the present 200 becquerels to 10.