By Shigeki Hiroe,
A nonprofit in Fukushima Prefecture has been measuring for radioactivity in fish and seawater as the Japanese government prepares to release treated water from the crippled Fukushima Daiichi nuclear plant later this summer.
Comprising 13 members, many of whom are mothers with no prior experience in taking scientific measurements, the group is driven by serious concerns over how the discharge of radioactive water into the Pacific Ocean might affect the environment and children's health.
Learning the monitoring techniques from experts, they continue to fine-tune their operation.
"Unless we gather data now, we won't know if there is any impact after the release," a member of the NPO said. "We need to take accurate measurements now to eliminate our concerns about the effects on growing children."
Called the Mothers' Radiation Lab Fukushima -- Tarachine, the NPO was founded in the prefectural city of Iwaki in November 2011, eight months after the nuclear accident caused by the devastating earthquake and tsunami that slammed Japan's northeastern coast on March 11 of the same year.
The group began by measuring homegrown vegetables, rice and soil brought in by citizens concerned about radioactive contamination. According to the NPO, the word Tarachine comes from the Manyoshu, Japan's oldest selection of poetry, and means mother or someone who fights to protect her children.
Tarachine found "hot spots" with localized high radiation levels in city parks and informed the prefectural government, leading to decontamination work.
Much of its 100 million yen ($700,000) operating budget is covered by donations.
Noriko Tanaka, 44, who is in charge of measurement at the NPO, is a former pastry chef. She has learned measuring techniques by visiting analytical laboratories and asking questions of academic specialists.
"I am just an ordinary mother. When I cannot make a proper analysis, I am persistent in sending questions to the professionals until I get the answers," Tanaka said.
When she joined the group in 2018, Tanaka often had trouble removing impurities from samples and could not make reliable measurements. However, her skills have improved to a degree that she now can take measurements that fall within the margin of error that would be acceptable at an analytical laboratory.
After the nuclear accident, Tanaka was laid off from her job at a cake shop, which temporarily closed. She was pregnant at the time and anxious about what to eat. "I feared the radiation exposure and wouldn't let my (baby) play outside too much," she recalled.
When she learned to take her own measurements, she was able to identify foods that tend to retain comparatively large amounts of radioactive material, such as mushrooms.
"We are helping mothers by releasing this data. We want them to use the data as a basis for making informed decisions and have peace of mind about how to raise their children," she said.
Since September 2015, Tarachine has obtained water and fish samples for measurements from the sea off the Fukushima Daiichi plant two to four times a year. It has so far found no tritium.
Tokyo Electric Power Company Holdings Inc. is using an advanced liquid processing system that removes radionuclides, but tritium will remain as it is difficult to eradicate.
As radioactive substances are carried to shore by sea currents, Tarachine began beach surveys in April 2020. By introducing a new device, the group improved its detection limit from 2 becquerels to 0.2 becquerels per liter.
The International Atomic Energy Agency said in a recent report that equipment built at the plant to release the treated water is safe and consistent with internationally accepted nuclear safety standards. Prime Minister Fumio Kishida has stated that the government's plan to pump the water out this summer remains unchanged.
Tarachine has received several interview requests from South Korean, Chinese, British and other foreign news media about the scheduled release. Japan's neighbors are particularly concerned about the possible impacts of the water reaching the regional ecosystem.
"The release of treated water is not a problem limited to Fukushima because there are no walls in the sea. We will continue to double-check measurement results from the government and TEPCO," said Ai Kimura, 44, secretary-general of the group.
