FUKUSHIMA–Food lovers often look forward to autumn and winter, when the savory zing of mushrooms is found in hearty soups and other tasty dishes.
But the fungi might be in short supply this year following the disaster at the Fukushima No. 1 nuclear power plant.
Mushrooms are thought to absorb radioactive substances like sponges absorb water. Bans have been imposed on the shipment of mushrooms from Fukushima Prefecture, one of nation’s main mushroom production centers, because of the radiation leakage from the quake-stricken plant.
Tree logs, used as a medium to grow mushrooms, have emerged as possible culprits for radioactive contamination. The farm ministry and the prefectural government are busy trying to come up with response measures.
“This is the biggest crisis in my 60-year-long professional life,” said 78-year-old Chusuke Saito, who grows “shiitake” and Jew’s ear mushrooms in Fukushima city. Revenue has plunged to one-fifth the level before the March 11 disaster at his direct sales outlet. The wholesale price offered to the farmers’ cooperative has also been cut by half.
Radioactive cesium exceeding the safety standard of 500 becquerels per kilogram was first detected in April in shiitake mushrooms grown on tree logs outdoors. More cases of radiation in Fukushima mushrooms were detected, and shipment bans were put in effect in 16 municipalities. The bans were still in effect as of Sept. 6.
Prices for mushrooms grown indoors in trays, like at Saito’s farm, are also plummeting.
It was initially believed that cesium discharged from the stricken Fukushima No. 1 nuclear plant had settled on mushrooms grown outdoors. In July, however, excess radioactive substances were detected in shiitake mushrooms grown indoors, indicating the possibility that cesium had been absorbed from contaminated tree logs.
The farm ministry plans to analyze the actual levels of contamination in the tree logs and to publish, in the near future, transfer factors from tree logs to mushrooms and safety standards for using tree logs that contain cesium.
If tree logs are the culprits of contamination, that may have far-reaching repercussions.
Contamination has been spotted in wild mushrooms as well, dealing a blow to tourism activities.
[box_light]Many people collect wild mushrooms in Tanagura. In September, however, 56 times the safety standard of cesium was detected in wild “chichitake” mushrooms, and a ban was imposed Sept. 6 on shipments of “matsutake,” which belongs to the same species group.[/box_light]
The mountain is usually open to mushroom gatherers in late September, but that looks difficult this year. The Mushroom Festival in October was also canceled.
The matsutake mushroom association has taken care of mushrooms using entrance fees collected from gatherers. Last year, the mountain had more than 100 daily visitors on the best of days during the matsutake season that ran through late October.
“What should we do now?” said the matsutake association member. “The mountain may go to ruins if we don’t take care of it.”
Tree logs used for fungiculture are harvested in winter and are stored outdoors until they are inoculated with spawn in spring. Cesium is likely to have fallen on tree logs that lay outdoors when the nuclear accident occurred.
Sawdust used in indoor tray cultures is also made from tree logs, so the possibility of contamination through that route cannot be ruled out.
There is a possibility that contaminated tree logs and sawdust have been shipped both within and outside Fukushima Prefecture. This led the farm ministry to advise relevant industry associations on Aug. 12 to refrain from the sale and use of tree logs and other products from the prefecture until their safety is confirmed.
The Fukushima prefectural government is also investigating the destinations of tree logs and other products shipped from the prefecture. The investigation results are expected to be released shortly.
- Radioactive Chestnut from Fukushima, 2,040 Bq/Kg (enformable.com)
- Wild Mushrooms in Fukushima Tested Found As Contaminated As Mushrooms After Chernobyl (enformable.com)
- Radioactive Leaf Tobacco, 217 Bq/Kg of Cesium – 30 Bq greater than after Chernobyl (enformable.com)
- Wild Mushroom in Fukushima Tested 28,000 Becquerels/kg of Radioactive Cesium (ex-skf.blogspot.com)
- Japan’s nuclear crisis minister promotes radiation reducing technology (enformable.com)
- Japan to use Prussian Blue and other solutions to remove radiation from soil (enformable.com)
- Fish caught in river north of Tokyo exceeded legal limit for radioactive cesium – First time seen outside of Fukushima (enenews.com)
- Issue of radiation-tainted food in Japan escalates – Half of Japan’s rice is grown in range of emissions from Fukushima (enformable.com)
- Extreme soil contamination detected over 40 kilometers away from quake-stricken Fukushima plant (enformable.com)
- Fukushima Pref. shows how it tests rice for radioactive matter (enformable.com)