Beneath the elegant curves of the roof on the Seirinji Buddhist temple in Japan’s Fukushima region hangs an unlikely adornment: a Geiger counter collecting real-time radiation readings.
The machine is sending data to Safecast, an NGO born after the March 2011 Fukushima nuclear disaster that says it has now built the world’s largest radiation dataset, thanks to the efforts of citizen scientists like Seirinji’s priest Sadamaru Okano.
Like many, Okano lost faith in the government after the nuclear meltdown seven years ago.
“The government didn’t tell us the truth, they didn’t tell us the true measures,” he said.
Okano was in a better position than most to doubt the government line, having developed an amateur interest in nuclear technology 20 years earlier after the Chernobyl disaster. To the bemusement of friends and family, he started measuring local radiation levels in 2007.
“The readings were so high, 50 times higher than natural radiation,” he said of the post-disaster data. “I was amazed. The news told us there was nothing, the administration was telling us there was nothing to worry about.”
Norio Watanabe has been a Safecast volunteer since 2011. In the days after the disaster evacuees flocked to Koriyama, which was outside the evacuation zone. He assumed his town was safe.
He sent his children away, but stayed behind to look after his mother, a decision he believes may have contributed to his 2015 diagnosis of thyroid cancer.
“As a scientist, I think the chance that it was caused by the Fukushima accident might be 50-50, but in my heart, I think it was likely the cause,” he said.
His thyroid was removed and is now healthy, but Watanabe worries about his students, who he fears “will carry risk with them for the rest of their lives.”
Safecast now has around 3,000 devices worldwide and data from 90 countries. Its counters come as a kit that volunteers can buy through third parties and assemble at home.
Read more at Tracking Fukushima’s radiation