Deadly asbestos has been found in equipment imported from China for a Port Pirie smelter redevelopment project, the South Australian government says.
The illegal material was found by project developer Nyrstar in the plaster coating of eight metal vessels, with one vessel being at least 10 metres tall.
Safework SA learnt of the find nearly two weeks ago and shut down construction near the asbestos, which Nyrstar is now trying to remove.
An investigation by Safework SA has found the material was imported from China over the past year and that workers who may have been exposed to the asbestos were wearing protective gear.
SA deputy premier John Rau says it is the Australian Border Force's responsibility to keep the illegal product out and has requested urgent talks with Immigration Minister Peter Dutton.
"It is disgraceful that more than ten years after a total ban on asbestos was imposed across the nation, Commonwealth border guards are still failing to keep these products out of this country," Mr Rau said in a statement.
The Australian Workers Union has called for a full inquiry into the incident.
"We need to find out how on earth a contractor thought it was appropriate to deliver an asbestos-laden piece of equipment to an Australian site," AWU national secretary Scott McDine said.
"This is hardly an isolated incident. Border security needs proper resourcing to keep Australians safe from asbestos-related disease."
Independent senator Nick Xenophon called for an audit of all building products imported into Australia over the last five years.
The $563 million transformation of Port Pirie's ageing lead and zinc smelter to a multi-metals processing facility is planned for completion in the second half of 2017.