The town that radioactivity built

On the afternoon of September 13, 1987, a radiotherapy source containing the highly reactive isotope cesium-137 was taken from an abandoned hospital in Goiânia, the capital of the Center-West state Goiás. The chain of events that followed this seemingly harmless theft led to what was the world’s biggest ever urban nuclear accident, until the Fukushima disaster in 2011.

Fueled by curiosity, naïvety, and poverty, young waste pickers Roberto dos Santos Alves and Wagner Mota Pereira broke into the abandoned Goiás Radiotherapy Institute building, just outside the Goiânia city center. The institute had moved to another facility two years prior but left some equipment behind, including a teletherapy unit containing cesium-137.

The two men left the building with the 122-kilogram piece of equipment loaded onto a wheelbarrow, divided into two cylinders.

From there, the pair returned to Mr. Alves’ home, where they attempted to dismantle the capsules, releasing the radioactive cesium into the local environment for the first time. The bright blue cesium-137 powder released from the capsules circulated through at least four Goiânia neighborhoods, contaminating hundreds of people in the space of a few days, and thousands more in the years that followed.

Brazil’s biggest ever urban nuclear accident

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