Goldfields mercury scare fallout leaves locals in Kalgoorlie seeking answers
Police raided 17 properties in three days during a large-scale operation in Kalgoorlie-Boulder. (Supplied: WA Police)
Mercury is a naturally occurring metal that is used in a range of everyday products, including thermometers, electrical switches and light bulbs, so why is it so hazardous to human health?
At ambient temperature and pressure, mercury is a silvery-white liquid but once it is heated and vaporises, the World Health Organisation (WHO) says it can stay in the atmosphere for up to a year.
According to the WHO, mercury can be fatal if inhaled and harmful if absorbed through the skin.
There are a range of serious health impacts, including brain and neurological damage, especially among young children which is why authorities in Western Australia’s Goldfields have been on red alert.
Last month, police uncovered several backyard gold smelting operations in the historic mining city of Kalgoorlie-Boulder, where the precious metal was allegedly being laundered for cash to fund illicit drug operations.
Police raided 17 properties during a three-day operation coordinated by the Kalgoorlie-based Gold Stealing Detection Unit, between January 15 and 17, and found mercury contamination at several locations.
About 30 tonnes of allegedly stolen gold-bearing ore was seized and 20 people were charged, including several members of the Mongols outlaw motorcycle gang.
A subsequent raid at a property neighbouring East Kalgoorlie Primary School last week discovered mercury contamination, with the school yet to reopen.
Curtin University’s WA School of Mines (WASM) has been called on multiple times in recent weeks to safely dispose of the seized mercury at laboratory facilities at its Kalgoorlie campus.
WASM associate professor of metallurgy Laurence Dyer said mercury had traditionally been used in artisanal gold mining, but had been largely phased out by large-scale miners.
He said industrial purchases of mercury required a licence, and the metal was most dangerous as a gas.
“It’s pretty inert in its liquid form … pretty stable,” he said.
“But as soon as you warm it up and expose it to the atmosphere, then you’re in a world of hurt.
“The vapour … so once it’s a gas, once it’s been evaporated, then it’s super toxic. And the other problem is it accumulates in your bloodstream.”
A quick Google search and dozens of online videos posted to YouTube pop up showing how to recover gold from what is known as a mercury amalgamation using a retort set-up.
Done incorrectly, it can result in serious health issues, as one convicted gold thief found out at Coolgardie in 2018.
“If you don’t do it properly, it is super dangerous,” Dr Dyer said.
“It’s usually only a couple of hundred grams of mercury, so not a huge amount, but it’s certainly enough to cause a lot of damage in a small area.
“If you get a windy day, it’ll move a fair way. The risks are there.”
Mercury poisoning affects the body’s immune system and can lead to kidney damage and damage to the digestive system.
According to the WHO, about 80 per cent of inhaled mercury vapour is absorbed in the blood through the lungs.
Garth Maker, associate professor of biochemistry at Murdoch University, said in cases of low-level exposure the body’s normal defence mechanisms could deal with mercury.
He said the metal posed the greatest risk to fetuses and infants.
“The brain, the nerves and muscles are particularly affected,” Dr Maker said.
“That’s why we would be always very concerned when children and young people are exposed to mercury because obviously, their brains are still developing.
“The potential impact is greater for children than it would be for someone fully grown.”
Speaking in Kalgoorlie on January 24 after the raids were made public, WA Police Minister Paul Papalia revealed mercury and arsenic were being used in the clandestine operations.
He said it had the potential to contaminate local water supplies.
“Incredibly dangerous, easily contaminating the environment around them, potentially vaporising and becoming more dangerous and easily consumed by people in proximity to it. It’s just all manner of stupid that this did this,” Mr Papalia said.
Dr Maker said contaminated water supplies were how most people were exposed to mercury around the world.
Two doctors have been on site this week offering free mercury testing for 150 East Kalgoorlie students who have been temporarily relocated to the South Kalgoorlie Primary School.
The WA Country Health Service has told the ABC there have been no reported cases of mercury poisoning at Kalgoorlie Regional Hospital so far.
The state government has been testing water sources and soil at the school but has not publicly released its findings.
Dr Maker said there should be no cause for alarm in Kalgoorlie-Boulder but people concerned should get tested.
“If someone was to, for example, accidentally break up into mercury thermometer and ingest that mercury, we’ve got a pretty good idea of how it’s going to affect them and we can get on and treat them very quickly,” he said.
“What we don’t always know is what happens when someone’s exposed to a low level of mercury over a long period of time.
“So this is where it’s going to be important that any individuals who have potentially been exposed are aware of this and are able to monitor their own health over a period of time.”