The Citizen Scientists of Fukushima

Every year when winter finally loosens its grip on northern Japan, Tomoko Kobayashi begins what has become an annual rite for her and a small band of collaborators. They head out with measuring devices to keep tabs on an invisible threat that still pollutes the mountains and forests around their homes: radioactivity.

In her car, Ms. Kobayashi follows a route that she now knows by heart, making regular stops to probe the air with a survey meter, a box with a silver wand that looks and acts like a Geiger counter. She uses it to detect gamma rays, a telltale sign of the radioactive particles that escaped when three reactors melted down at the Fukushima Daiichi nuclear plant in March 2011 after an undersea earthquake sent a towering tsunami crashing into the coastline.

She and a group of fellow residents of Odaka, a small community 10 miles north of the plant, spend days collecting readings at hundreds of points, which they use to create color-coded maps of radioactivity levels emanating from reactor particles still scattered across the countryside. Ms. Kobayashi posts them on the wall of her small inn for guests to see, making up for a lack of government maps detailed enough to reveal potentially hazardous spots.

“The government wants to proclaim that the accident is over, but it isn’t,” said Ms. Kobayashi, 72, who reopened her inn, Futabaya, seven years ago, after the evacuation order in Odaka was lifted. The inn has been in her family for four generations and she grew up here, never imagining she would one day have to master an arcane knowledge of microsieverts and atomic half-lives.

“I choose to live here, but is it safe? Can I pick these nuts or eat those fruit? The only way to know for sure is do the measuring ourselves,” she said.

Ms. Kobayashi is one of Fukushima’s citizen scientists, residents around the plant who responded to official coverups and silences by acquiring their own measuring devices and teaching themselves how to use them. They defied a government that at first tried to prohibit nonprofessionals from measuring radiation and later just ignored them.

Almost 14 years after the meltdowns, the citizen scientists persist, fueled by smoldering distrust of authority. While their numbers have dwindled as some grew old or moved away, many like Ms. Kobayashi remain vigilant, eager to make their voices heard or simply reclaim control of lives shattered when towns around the plant were evacuated or contaminated.

They have created new communities with their networks of like-minded people. By filling gaps left by government inaction, they have grown proficient at measuring and mapping invisible radiation, leading to what experts have called a democratization of expertise. This grass-roots embrace of science is an enduring legacy of the Fukushima disaster and a path to self empowerment.

“Around the world, we have seen a growing contempt for expertise, but these citizen scientists are going against that trend,” said Kyle Cleveland, a sociologist at Temple University in Tokyo who has researched perceptions of radiation during the Fukushima crisis. “They are using knowledge to understand their environment and claim legitimacy for their grievances.”

While the citizen scientists were often the only source of radiation numbers in the months after the meltdowns, these days they play watchdog, verifying the government’s figures and providing a level of detail that officials still won’t. After falling for several years, radiation outside the plant has plateaued at levels often still many times higher than before the accident.

Some groups have achieved considerable expertise in detecting these invisible particles. One is the Mothers’ Radiation Lab Fukushima — Tarachine, started by a group of mothers in the city of Iwaki, an hour’s drive south of the plant, to protect their children.

Begun in a single room with three donated measuring machines, Tarachine now occupies almost the entire floor of its building, with 13 salaried staff, a health clinic and a laboratory filled with equipment. Its self-taught technicians, most of them mothers, can measure even tough-to-detect types of radiation. They publish their findings on the group’s website.

When the nuclear power plant’s reactor buildings started to explode, the group’s founder, Kaori Suzuki, was a homemaker whose only outside work had been a brief stint in the fashion industry. Anxious for her teenage daughter, Ms. Suzuki joined protests against the lack of official information before concluding that the best response was to learn to measure radiation herself. When other mothers joined, they chose the name Tarachine (pronounced tah-rah-chee-nay), a term from ancient Japanese poetry used to describe a strong mother figure.

They faced enormous resistance from official scientists dismissive of their efforts and social pressure from fellow residents fearful of radiation-related discrimination similar to that faced by the survivors of the atomic bombing of Hiroshima and Nagasaki. Ms. Suzuki learned to use the machines by deciphering English-language manuals. Once Tarachine’s doors opened, demand was overwhelming, as parents brought food from supermarkets and farmers handed over their own produce to be measured.

“Within one month, we had a three-month waiting list,” she recalled.

Worries about food declined as radiation levels dropped, but Ms. Suzuki, 59, has taken on other concerns. One is the decision by the Fukushima plant’s operator, Tokyo Electric Power Co., to begin releasing into the Pacific Ocean more than a million tons of water that has been treated but remains contaminated. Tarachine now sends out boats.

“We still have to keep verifying the company’s claims,” Ms. Suzuki said.

In Tsushima, a small village nestled in a narrow valley surrounded by dark peaks, only the area along the main street has been decontaminated. The rest, 98.4 percent of the village’s land, remains off-limits with radiation levels that can still reach hundreds of times above normal.

At the height of the accident, a plume from the plant reached Tsushima during a snowstorm, lacing the falling flakes with dangerous isotopes. These soaked into the ground, heavily contaminating the village despite its location 18 miles from the reactors.

While the small central area was reopened two years ago, only five people have returned from a previous population of 1,400. One hoping to restart his life here is Hidenori Konno, 77, who was born and raised in Tsushima. He makes frequent trips back to fix the century-old ryokan inn that has been in his family for generations.

During those visits, Mr. Konno uses a handheld device to map radiation readings in the village. By identifying places to avoid, he hopes to convince former neighbors that it is safe to come back.

“If we can see where the hot spots are, and know how much risk we’re actually taking, then I don’t feel as frightened about returning,” Mr. Konno said, sitting on a tatami mat in his inn, which sat empty for 12 years while the village was evacuated.

Helping him is Shinzo Kimura, a radiation scientist who is setting up a small lab in an old clay storehouse behind the inn. During the disaster, Dr. Kimura quit his job at a government research institute near Tokyo, which tried to block him from taking measurements around the plant. He moved to Fukushima, where he has taught locals like Mr. Konno how to make radiation-hazard maps.

“Science gives them a way to visualize a radioactive danger that they cannot see, smell or taste,” Dr. Kimura said. “It restores what the accident robbed from them, which is an agency over their own lives.”

For Ms. Kobayashi, owner of the reopened inn in Odaka, it was her own maps that reassured her about moving back. She said citizen scientists must stay on the lookout for new leaks, with the cleanup expected to take several more decades.

“The radiation is not gone,” she said, “nor is the need to protect ourselves.”

Kiuko Notoya contributed reporting.