Radioactive substances expert perplexed at how dangerous capsule ‘has fallen off the back of a truck’ in WA

The disappearance of a dangerous radioactive capsule in Western Australia has sparked calls for tighter radiation safety as authorities continue to search a 1,400 kilometer stretch of road for the small object.

Key points: The capsule was lost during transport along a 1,400 km route in WAA an expert in the field says it is clear that the device is insufficiently protected. He says changes must be made to ensure that this cannot happen again

An urgent warning remains in place after the cesium-137 capsule, just 6 millimeters in diameter and 8 mm long, was reported missing on January 25.

It was lost between January 11 and January 16 in transit somewhere between a Rio Tinto mine site in northern WA and a depot in the Perth suburb of Malaga.

Specialized equipment to detect radiation was brought in to help a multi-agency incident management team search the route more efficiently.

An incident management team searches for the tiny radioactive capsule on the Great Northern Highway.(Supplied: DFES) Sequence of events ‘remarkable’

Authorities believe the small capsule fell out of its packaging, and through a small hole in the truck where a bolt had come loose.

Curtin University associate professor and radioactive materials expert, Nigel Marks, described the sequence of events that led to the loss of the capsule as “remarkable”.

“Right now, I don’t think anyone can quite believe that something that is highly radioactive fell off the back of a truck,” he said.

“Obviously, if you can get a few screws loose and then a bolt is missing and then your source escapes, that’s just not enough protection.”

Associate Professor Marks said that, despite strict safety measures already in place for handling radioactive materials, further investigation was needed into how such incidents could be avoided in the future.

“It’s a regulatory failure. They thought they had enough levels of containment, but of course they didn’t,” he said.

“It’s probably a case of [people] to become too familiar with the radioactive materials … with familiarity can only become a lack of awareness of the things that can go wrong, such as we have in this situation.”

Authorities admit it is possible the capsule will never be found.

Alarm arose in some communities

The possibility of it being undetected has left some communities along the truck’s route extremely worried.

Sandy Davies, chair of the Geraldton Region Indigenous Medical Service, was concerned that people would be at risk of health problems if the capsule came into contact with them.

“I think it’s pretty concerning for everybody in that area … because a lot of our people are out of the woods all the time and they’re pulling on the side of the road,” he said.

The search for the small capsule began last week. (Supplied: DFES)

Mr Davies said someone must be held accountable for putting the public at risk.

“There are questions that need to be answered,” he said.

However, other communities are not so concerned.

“Most of the people who come in here, they talk about things that are going on and nobody has even mentioned it,” said Sue Schmidt, manager of Wubin Roadhouse.

Located in the Wheatbelt region, Wubin sits at the intersection of some popular routes, including the Great Northern Highway – the road on which the capsule is believed to have been lost.

Rio Tinto says a Geiger counter was used to “confirm the presence of the capsule inside the package” before it left its site. (ABC News: Cason Ho)

Ms Schmidt said as the town was a prominent transport hub for truckers, it would be useful for them to know which trucking company was involved in transporting the capsule.

“We have a pretty big area here with parking and stuff [so] it will take a long time for us to go around and look around,” she said.

“So if we had an idea of ​​whether or not this is a company that comes in here all the time or not, then maybe we could look a little further.”

She said despite being located near the search area, there was no communication from the authorities.

The incident management team is using specialist equipment for the search. (Supplied: DFES)

“No one notified [or] talked to us about anything to do with that … I think everyone seems to be pretty much in the dark,” Ms Schmidt said.

“There are a lot of people who don’t read the paper or listen to the news, so even if they put some kind of sign in front of the roadhouse or in a way to let people know, [that] will likely be beneficial.”

Health risks ‘extremely concerning’

The cesium-137 capsule is part of a radiation meter commonly used in processing plants.

The radioactive source emits radiation that is reflected back to the meter to detect the density of materials.

This image shows the size of the container in relation to a 10-cent coin. (Provided: DFES)

Health authorities have warned that standing within a meter of the capsule is equivalent to receiving 10 chest X-rays in an hour and have urged anyone who finds it not to go near it.

Deputy Prime Minister Roger Cook said the potential danger of the situation was extremely worrying.

“My understanding is that if you come into close contact with the capsule, you run the risk of radiation burns or chronic illness and possibly death,” he said.

“And that’s why we’re putting all these resources into trying to recover it.”

He said a thorough investigation would be undertaken by the Radiological Council to ensure that this does not happen again.

“Obviously there are a lot of things in place to ensure that these things don’t happen.

Roger Cook says the potential danger of the situation is extremely worrying. (ABC News: Keane Bourke)

“The fact that this capsule is now lost is obviously a source of great regret and very disappointing,” he said.

“We look forward to finding out what happened in this incident [and] learn from it so we can put extra measures in place, but the most important thing is to recover that particular capsule so it doesn’t pose a danger to the public.”

Andrew Robertson, WA’s chief health officer, said radioactive material was routinely transported across the state, under strict regulations.

“It is extremely rare for a source to be lost,” he said.

“There are thousands of sources in WA as they are commonly used in medicine, industry, mining, education, research and calibration sectors under safety procedures.