GWEN IFILL: Next, the last in our special series on the aftermath in Japan, one year after the nuclear accident at Fukushima.
NewsHour science correspondent Miles O'Brien has been reporting on the continuing concerns in the region, including fears of contamination.
Tonight, how Japanese citizens are grappling with very real questions about farming and food safety.
MILES O'BRIEN: In his barn, rice farmer Toshiyuki Nishiyama has all the latest gear get the job done. This planter will sow six rows at a time, but these days his farm machines are in mothballs and his fields lie fallow.
Toshiyuki and his wife, Fumiko, are back home alone in the village of Kawauchi, about 13 miles from the Fukushima Daiichi nuclear power plant. The village is not officially in the mandatory evacuation zone, but it is contaminated with cesium fallout, and the farmers were told not to plant their rice fields. So the place is all but abandoned.
"I was born and grew up here," Toshiyuki told me. "But this land and these houses are inherited for generations. We have to protect them. So we can't help but return."
But it is not easy living here now. The Nishiyamas drive more than an hour just to stock the fridge. And everywhere they turn, they are reminded of happier times, when they measured their children's height on this door frame.
So this is?
They showed me pictures of them and the grandchildren, all gone now because they do not believe it's safe to live here anymore, for fear of radiation contamination in the air and in the food. In food, radiation contamination is commonly measured in a unit known as Becquerels. The government here initially set the limit at 500 Becquerels per kilogram of food, but there is talk of lowering it to 100. The limit in the U.S. is 10 times higher.
"The stricter standard is indispensable for everyone to feel safe," Toshiyuki told me.
But the confusion about what levels are truly safe has triggered widespread unease all over Japan. People are skeptical of government assurances the food is safe. And so an ad hoc cottage industry of radiation testing services is filling the void.
Business is robust at this testing facility in Kashiwa, a hot spot at the outskirts of Tokyo. The manager says they have measured food with several hundred Becquerels of contamination.
Yuka Sasaki came here to test some fruit from the place where her son's kindergarten class was headed on a strawberry-picking field trip. It turns out the berries were safe and the trip was a go.
"Those who have little kids or grandchildren are careful about milk, mushrooms and some other foods," she said.
At this store in Tokyo, they are promoting produce grown in Fukushima, but they claim it is all tested for radiation. Cesium readings are posted right beside the price. Manager Motoi Kitazawa says it is the right thing to do for farmers enduring such hardship.
"Most crops read below 10 Becquerels. Actually, measuring radiation, we realize there are not so many reading high radiation. So it's really important to inspect and release information. Then farmers can confidently ship their crops and customers can feel safe to buy them. I hope this kind of effort spreads."
But Sachiko Sato is not so sure. She channeled her worries into a nonprofit in Fukushima City that sells produce she purchases from outside the region. When a shipment comes in, as these dry radishes did on the day we met, she walks a few blocks to a testing center to ensure they are okay to eat. Turns out these were harvested before the meltdown and most certainly safe, so they were fine to put on the shelves.
Do you think it's not safe to buy food at a typical market right now?
"I think food in the market is not safe," she said. "If they're inspected and data are released to the public, I would feel safe. I'm concerned because an inspecting system has not been established yet."
That's why Jinko Iseki shops for her children here.
"I'm concerned," she said. "I can't trust the safety standards set by the government."
Many here believe the government is placing business interests over people's health. It turned Ryoko Sashizaw and her American expat husband, David Sydney Moore, into radiation testing activists.
DAVID SYDNEY MOORE, American: Two-inch sodium iodide, NaI, thallium-doped, scintillation probe.
MILES O'BRIEN: They've spent more than $5,000 on sophisticated radiation sensors and began testing their Tokyo neighborhood of Suginami for hot spots, bringing contaminated soil back home, because there's no place to legally dump it.
There's no place to put it?
RYOKO SASHIZAW, Tokyo, Japan: No. Yeah.
MILES O'BRIEN: But it's okay. . .
MILES O'BRIEN: Right? That's what you hope.
DAVID SYDNEY MOORE: Now we have got 1,238 followers.
MILES O'BRIEN: They started posting their readings on a Facebook page. And now people send them a steady stream of soil and food to test. He says food from Fukushima should be banned entirely, the farmers compensated for their losses.
DAVID SYDNEY MOORE: The only thing to do is to cut the product from the market 100 percent until we can guarantee a certain amount of stability.
Wow. Do you want to play something or do you want to watch something?
MILES O'BRIEN: For now, they are feeding their young boys purified water, rice harvested before the meltdown, and food they feel certain is safe.
RYOKO SASHIZAW: We are unusual. We -- I don't know anybody else who spends as much time, labor and money as we've done around us.
MILES O'BRIEN: Yes. Worth it?
RYOKO SASHIZAW: Yes, yes, because adults need to do it. Adults, we're responsible.
MILES O'BRIEN: But the stress has taken a toll, and they will soon be moving back to the U.S.
So how long will people in Japan be dealing with this problem? Many farmers here were dismayed to learn crops that did not have any direct contact to the Fukushima fallout were still too tainted to be brought to market.
KATHRYN HIGLEY, Oregon State University: They were a little bit surprised at how much of the cesium translocated from the old leaves into the new growth, particularly in the tea leaves.
MILES O'BRIEN: Radio ecologist Kathy Higley is reading Fukushima tea leaves at Oregon State University. She studies how radionuclides move through the environment.
KATHRYN HIGLEY: When the initial releases occurred, the radionuclide contamination fell to the ground and it contaminated the old, mature plants, the old, mature leaves, if you will. And later on, as the weather warmed up and you started getting new growth, what they found in the tea leaves was that the new growth was also contaminated.
MILES O'BRIEN: Whatever the mechanisms, Toshiyuki Nishiyama is not waiting for the soil to be safe enough for rice. He and some of the others who used to farm here are thinking of building greenhouses to grow vegetables hydroponically.
"I believe everyone is angry about this situation because our lives are devastated," he told me. "It's furious anger, but how can we express our anger?"
And fully aware of the irony, he took me to another barn to show me this: the bags of rice this lifelong rice farmer had to buy at the market.