A small radioactive capsule that went missing last week has finally been found somewhere in the desert in Australia after a massive search effort began.
Authorities in Western Australia, when announcing their discovery, declared that they had “virtually found the needle in a haystack”.
The missing silver capsule was only 8mm by 6mm, and is believed to have fallen from a lorry that had traveled 1,400km along Western Australia. His loss triggered a radioactive alert for large parts of the state.
On Monday, authorities said it would take five days to adjust the truck’s path. On Tuesday, they said 660 kilometers had been searched so far, and that a team from the country’s nuclear safety agency had now joined the hunt.
How could this happen, and how dangerous is this capsule? Here’s what you need to know.
How did the radioactive capsule get lost?
It is believed that the capsule fell from a lorry with multiple trailers traveling on the red roads of the Western Australian desert towards the city of Perth, sometime between January 12 and January 16.
Authorities suspect the capsule, which is part of a gauge used in mining equipment, fell out of its casing after vibrations from bumpy roads caused the screws to loosen.
The van left on January 12th, and the wrapper reached the outskirts of Perth on January 16th. But it wasn’t until nine days later, on January 25, that the truck was unloaded by mining giant Rio Tinto for inspection – and the loss of the capsule became apparent.
Western Australian authorities alerted the public about the disappearance on 27 January, two days after they were notified by Rio Tinto.
It feels like the opening sequence of a horror movie where disasters are often triggered by the smallest of accidents. But the danger posed by losing this radioactive capsule was very real.
The Western Australian Fire and Emergency Services Department said on Monday that radiation specialists had been searching for the small capsule on the Northern Highway by “driving north-south at slow speed”, but to no avail.
People in the state have also been warned that the capsule may have unknowingly lodged in their car tires – and thus traveled further.
Rio Tinto has stated that it is “sorry” for causing public concern and that it takes the incident very seriously.
What is this radioactive capsule?
Experts relied on radiation detection equipment to find this silver capsule, which is smaller in diameter than a 1 euro cent coin and looks a bit like a button battery.
It’s a 19-GBq (which stands for gigabecquerel, a unit that indicates radioactive decay), a ceramic source of cesium-137, the type typically used in radiometers. These devices use radioactive sources to measure parameters such as the thickness, density, and moisture of various materials and surfaces to allow the construction of safe buildings, roads, and other projects.
Capsules such as lost capsules are usually used in the mining, oil and gas industries.
The cesium-137 contained in the capsule is a radioactive metal that emits dangerous beta and gamma radiation.
Its half-life is 30.05 years, which means that it takes that long for the metal to lose half of its original activity. It is coated with steel, which prevents radioactive materials from escaping.
How bad is a capsule disappearance?
Her disappearance was very bad, according to the authorities. The capsule emits dangerous amounts of radiation that can cause skin burns, while prolonged exposure may cause cancer.
Officials warned that spending an hour one meter from the missing capsule would be like undergoing 10 x-rays.
It could be worse, WA Radiation Services said, estimating the radiation dose from the capsule to be the equivalent of 17 chest radiographs.
In addition to exposure, there is also the risk of contamination. If the missing capsule is broken, the beta particles inside will cause serious harm to people’s health if they come in contact with or eat it.
A radioactive alert has been issued across parts of the Australian state and members of the public have been advised to stay at least five meters away from the radioactive capsule if they find it.
The risk to the general community was considered low, but the loss of the highly radioactive capsule along the Western Australian desert raised significant alarm in the region – and highlighted Rio Tinto.
A global mining group came under fire in 2020 for destroying a site of sacred importance to Indigenous Australians during an iron ore mine expansion.
The mining giant has now apologized for the loss of the small capsule.
“We clearly recognize this is deeply troubling and we regret the concern it has caused in the Western Australian community,” Simon Trott, head of Rio Tinto’s iron ore division, said in a statement Monday.
Meanwhile, the search for the missing radioactive materials continues.