A small radioactive capsule that went missing last week somewhere in the Australian desert has finally been found after a massive search effort began.
Announcing their discovery, Western Australian authorities said they had “literally found the needle in the haystack”.
The missing silver capsule was just 8mm by 6mm and was believed to have fallen from a truck that traveled 1,400km across Western Australia. Their loss triggered a radiation alert for much of the state.
Authorities said Monday it would take five days to get back on the truck’s route. On Tuesday, they said 660km had been searched so far and a team from the country’s nuclear safety agency had joined the search.
How could this happen and how dangerous was this capsule? This is what you need to know.
How was the radioactive capsule lost?
The capsule is believed to have fallen from a truck with several trailers driving along the red desert roads of Western Australia towards the city of Perth, sometime between January 12 and 16.
Authorities suspect the capsule, part of an indicator used in mining equipment, came loose from its casing after vibrations from the bumpy roads caused the bolts to loosen.
The truck left on January 12 and the casing arrived in suburban Perth on January 16. But it wasn’t until nine days later, on January 25, that mining giant Rio Tinto unpacked it for inspection, and the loss of the capsule became transparent.
Western Australian authorities alerted the public to the disappearance on January 27, two days after Rio Tinto notified them.
It sounds like the opening sequence of an apocalyptic movie where catastrophes are often triggered by the smallest incidents. But the risk posed by this missing radioactive capsule was very real.
Radiation specialists had been searching for the small pod on the Great Northern Highway “driving in a north and south direction at low speed” without success, the Western Australia Department of Fire and Emergency Services said on Monday.
People in the state were also warned that the capsule could have unknowingly lodged itself in the tires of their car and therefore traveled even further.
Rio Tinto has said it is “sorry” for causing public concern and is taking the incident very seriously.
What is this radioactive capsule for?
Experts teamed up with radiation detection equipment to find this silver capsule, which is smaller in diameter than a 1-cent coin and looks a bit like a button cell.
It is a 19 GBq (which stands for gigabecquerel, a unit indicating radioactive decay) cesium-137 ceramic source, the type typically used in radiation meters. These devices use radioactive sources to measure parameters such as the thickness, density, and moisture of different materials and surfaces to enable safe construction of buildings, roads, and other projects.
Capsules like the one that has disappeared are commonly 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 encapsulated by steel which prevents radioactive material from escaping.
How bad is it that the capsule was lost?
His disappearance was pretty bad, according to authorities. The capsule emits dangerous amounts of radiation that could cause skin burns, while prolonged exposure could cause cancer.
Spending an hour within a meter of the missing capsule would be akin to undergoing 10 X-rays, authorities warned.
Radiation Services WA said it could be even worse, estimating the radiation dose from the capsule equals 17 chest X-rays.
Beyond exposure, there is also the risk of contamination. If the missing capsule were to break, the beta particles contained within would cause serious damage to people’s health in case of contact or ingestion.
A radiation alert has been issued in parts of the Australian state and members of the public have been advised to keep at least five meters away from the radioactive capsule if they come across it.
The risk to the wider community was deemed to be low, but the loss of the highly radioactive capsule across the Western Australian desert has raised significant alarm in the area and has put Rio Tinto in the spotlight.
The global mining group came under fire in 2020 for destroying a site of sacred importance to indigenous Australians while expanding an iron ore mine.
The mining giant has now apologized for losing the small capsule.
“We recognize that this is clearly very concerning and we regret the alarm it has caused in the Western Australian community,” Simon Trott, head of Rio Tinto’s iron ore division, said in a statement on Monday.
Meanwhile, the search for the missing radioactive material continues.