CNN
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It’s like finding a needle in a haystack – an 8mm by 6mm silver capsule, no bigger than a coin. is believed to be lost Somewhere along the vast desert highway of Australia’s largest state.
Because authorities are so determined to find it, it contains Caesium-137, a highly radioactive substance that is potentially lethal.
Authorities in Western Australia believe the capsule, which emits both gamma and beta rays, fell into the back of a truck while it was being transported on a 1,400-kilometer (870-mile) stretch of the Great Northern Highway – a much longer distance than that. California coastline.
Mining company Rio Tinto, which used the density measuring capsule at its Gudai-dari iron ore mine, apologized on Monday, saying it was supporting the state government’s efforts to find it.
Rio Tinto said it checked all roads in and out of the mine in remote WA, where the device was located, before a contractor collected it for the journey south to the state capital, Perth.
Because of the capsule’s tiny size and the vast distances involved, authorities warn that the chances of finding it are slim.
And there are fears that it may already be carried further away from the search zone, potentially posing a radioactive health hazard to anyone who comes across it for the next 300 years.
State authorities raised the alarm on Friday, warning residents of the presence of radioactive fallout in the southern part of the state, including the northeastern suburbs of Perth, home to about 2 million people.
According to authorities, the capsule was placed in a package on January 10 and collected from Rio Tinto. Gudai-dari mine site by a contractor on January 12.
The car arrived in Perth on January 16 after spending four days on the road but was unloaded for inspection on January 25 – when it was discovered the capsule was missing.
“Upon opening the package, it was found that one of the four mounting bolts was missing and the gauge was broken with the source and all screws on the gauge also missing,” the Department of Fire and Emergency Services (DFES) said.
They believe strong vibrations caused by bumpy roads damaged the package – dislodging a mounting bolt that holds it in place.
Experts warn that exposure to cesium-137 can cause serious health problems for people: skin burns from close exposure, radiation sickness and the risk of potentially fatal cancer, especially for those unknowingly exposed for long periods of time.
Radiation Services WA, a company that provides radiation protection advice, says that standing within 1 meter (3.3 feet) of the capsule for one hour delivers about 1.6 millisieverts (mSv), about 17 standard chest X-rays.
Picking up the capsule will cause “severe damage” to your fingers and surrounding tissue, the company said in a statement.
Evan Kempson, associate professor of biophysics at the University of Southern Australia, said the worst-case scenario would be a curious child picking up the capsule and pocketing it.
“It’s rare but can happen and has happened before,” Kempson said. “There have been some past examples of people finding similar objects and suffering radiation poisoning, but they were much stronger than the current capsule missing.
“We are all exposed to a constant level of radiation from the things around us and the food we eat but the primary concern now is the potential health impact of the person who found the capsule.”
The incident came as a shock to experts who said the handling of radioactive materials such as cesium-137 is highly regulated with strict protocols for their transport, storage and disposal.
red river said it routinely transports and stores hazardous goods as part of its business and employs specialist contractors to handle radioactive materials.
Radiation Services WA Says radioactive materials are transported daily across Western Australia without any problems. “In this case, there appears to be a failure of the control system normally applied,” he said, adding that it had nothing to do with the loss of the capsule.
Pradeep Dev, a lecturer and radiation safety officer at Melbourne’s RMIT University, said damage to the capsule was “very unusual” because Australian safety regulations require them to be transported in highly protective cases.
The logistics company used to transport the device has not been named, Rio Tinto said.
Authorities have been searching for days along the truck’s route – from the Perth metropolitan area in the south and further north outside Newman, a small town near the mine site.
They drive white vehicles fitted with special radiation detection devices with flashing hazard lights slowly up and down the highway at speeds of 50 kilometers per hour (31 mph).
Dale Bailey, professor of medical imaging sciences at the University of Sydney, said the slow speed was needed to give the equipment time to detect radiation from the missing capsule.
“Radiation detectors in moving vehicles can be used to detect radiation above natural levels, but the relatively small amount of radiation at the source means that they have to ‘sweep’ the area relatively slowly,” he said.
DFES incident controller Darryl Ray said teams had searched more than 660 kilometers (410 miles) as of Monday and authorities hoped to complete the entire route by Friday.
In the event a member of the public stumbles upon the capsule, authorities have urged them to stay at least 5 meters (16.4 feet) away – although they admit it would be difficult to see from a distance.
“What we’re not doing is trying to find a tiny device by sight. We are using radiation detectors to detect gamma rays,” DFES officials said.
But there are fears it may no longer be within the search zone – authorities say the capsule could have stuck to the tires of another car, carried further away, or it could have been scattered by wild animals, including birds.
“Imagine if it’s a bird of prey that picks up the capsule and takes it away from the (main) search area – there’s a lot of uncertainty and it creates more problems,” said Dave Sweeney, a nuclear policy analyst and environmental advocate at the Australian Conservation Foundation.
“This source definitely needs to be restored and protected, but there are too many variables and we just don’t know what might happen.”
Caesium-137 has a half-life of about 30 years, which means that after three decades, the capsule’s radioactivity will be halved, and after 60 years, it will be halved again.
At this rate, the capsule could remain radioactive for the next 300 years, said RMIT University’s Deb.
“Caesium-137 is usually a sealed source — meaning, if it doesn’t break up, it won’t contaminate the soil or the environment … If the capsule is never found, it won’t contaminate or transfer radioactivity to the surrounding soil,” Dev added.
The University of Southern Australia’s Kempson says that if lost in an isolated area, “it’s unlikely to have much of an impact.”
Rio Tinto, one of the world’s largest mining giants, operates 17 iron ore mines in the Pilbara region of Western Australia. The company’s mining operations have sparked controversy in the past, including the destruction of two ancient rock shelters in 2020. Jukan GorgeAn apology prompts and The resignation of then-CEO Jean-Sébastien Jacques.
