By Mari Shibata
IWAKI, Japan, March 9 (Thomson Reuters Foundation) - At a laboratory an hour's drive from Japan's Fukushima nuclear plant, a woman with a white mask over her mouth presses bright red strawberries into a pot, ready to be measured for radiation contamination.
Six years after a massive earthquake off the coast of Japan triggered meltdowns at three of Fukushima's reactors, local mothers with no scientific background staff a laboratory that keeps track of radiation levels in food, water and soil.
As some women divide the samples between different bowls and handmade paper containers, others are logging onto computers to keep an eye on data - findings that will be published for the public to access.
The women on duty, wearing pastel-coloured overalls, are paid a small salary to come in for a few hours each day, leaving them free to care for their children after school.
"In universities, data is handled by qualified students, who have taken exams qualifying them to measure radiation. Here, it's done by mothers working part-time. It's a crazy situation," laughed Kaori Suzuki, director of Tarachine, the non-profit organisation that houses the mothers' radiation lab.
"If a university professor saw this I think they would be completely shocked by what they see."
Tarachine was set up 60 km (40 miles) down the coast from the Fukushima plant, in the city of Iwaki. After the magnitude 9 quake struck on March 11, 2011, triggering a tsunami, authorities declared a no-go zone around the plant.
Iwaki lay outside its 30 km radius, with lower radiation levels compared to the rest of Fukushima prefecture.
But with public announcements advising locals to stay indoors in the aftermath of the worst nuclear calamity since Chernobyl, the "invisible enemy" of radiation has continued to worry the mothers working at the lab.
NOTHING TO SEE, SMELL OR FEEL
"As ordinary citizens we had no knowledge about radiation at all. All we knew was that it is frightening," said Suzuki.
"We can't see, smell or feel radiation levels. Given this invisibility, it was extremely difficult for us. How do we fight it? The only way is to measure it."
To supplement readings by the Japanese government and the Tokyo Electric Power Company (TEPCO) that manages the nuclear plant, Tarachine publishes its own findings every month.
With donations from the public that helped them buy equipment designed to measure food contamination, the mothers measure radioactive isotopes caesium 134 and 137, and collect data on gamma radiation, strontium 90 and tritium, all of which were released during the Fukushima disaster.
Strontium-90 gravitates toward the bones when absorbed by breathing it, drinking it in water, or eating it in food. It can remain for years, potentially causing bone cancer or leukaemia.
Tritium goes directly into the soft tissues and organs of the human body. Although it is less harmful to humans who are exposed to small amounts of tritium every day, it could still be a hazard for children, scientists say.
The mothers say other parents trust the lab's radioactivity readings in local food more than those from the government.
"This issue is part of everyday life for these mothers, so they have the capability to spot certain trends and various problems rather than just accumulating expert knowledge," said Suzuki.
To handle potentially dangerous materials, the mothers have to study for exams related to radiation and organic chemistry.
"At the beginning I was just completely clueless. It gave me so much of a headache, it was a completely different world to me!" said Fumiko Funemoto, a mother of two, who measures strontium 90 at the lab.
"But you start to get the hang of it as you're in this environment every day."
As the lab only accepts items for testing from outside the exclusion zone, most results show comparatively low radiation levels.
But Suzuki says this is an important process and is especially reassuring to the parents of young children. The women also measure radiation levels in sand from the beach, which has been out of bounds to their children.
"If the base is zero becquerels (unit of radiation), and there is, say, 15 or 16 becquerels of caesium, that's still higher than zero. That means there is slightly more risk," Suzuki said.
"There are also times when you're like, 'Oh, I thought levels were going to be high there – but it's actually ok'. The importance lies in knowing what's accurate, whether it's high or low ... unless you know the levels, you can't implement the appropriate measures."
MINIMISING THE RISKS
Since official screenings began following the nuclear accident, 174 children in Fukushima prefecture have been diagnosed with - or are suspected of having - thyroid cancer, according to figures from Fukushima's local government.
Despite the International Atomic Energy Agency (IAEA)reporting in 2015 that an increase in thyroid cancer is unlikely, the mothers insist there is value in their work.
The first pictures from inside the nuclear plant were released by TEPCO in January, announcing it may have found nuclear fuel debris below the damaged No. 2 reactor - one of three affected by the 2011 disaster.
"In general, the issue of nuclear power is not really talked about much these days. It was talked about after the accident for about a year or so, but today, conversations mentioning words like 'radiation' don't happen anymore," Funemoto said.
"But I think the reality is different. The radiation isn't going to go away. That's why I'm doing this. So many places are still damaged. This idea that it's safe and that we shouldn't be anxious doesn't really add up."
Ai Kimura, another mother agrees. "My parents think I'm a bit paranoid. They keep saying, 'it's okay isn't it?" she said.
"But what if there's a chance that in 10 or 20 years time, my own child gets thyroid cancer? And I could have done my bit to minimise the risks. My children are mine and I want to do whatever I can to protect them."
(Editing by Ros Russell; Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, women's rights, trafficking, resilience and climate change. Visit news.trust.org)