One sample tested by specialists showed lead paint content of 2.2 per cent – more than twice the level recommended under Australian safety regulations. At that level it is regarded as "high risk exposure". Lead can be highly toxic when it is processed, or in this case welded, to produce dust, fumes or mist. It builds up in people’s bodies over time and continued exposure can lead to brain damage and kidney failure, among other problems. Whilst I am pleased the strict safety measures picked this issue up, these incidents are completely unacceptable. Transport Infrastructure Minister Jacinta Allan Employers are meant to manage lead exposure to workers and identify risky work. But the inadvertent lead exposure on big government projects draws attention to concerns about the use of toxic or dangerous building materials that do not comply with safety standards in Australia.

CFMEU assistant secretary Shaun Reardon Credit:Justin McManus Thousands of high-rise towers built around Australia in the last three decades are covered in cladding that is highly flammable. CFMEU assistant secretary Shaun Reardon attacked the West Gate Tunnel consortium’s safety record, which has included a worker being killed on the project last year. "This is a Victorian state government job and Victorian workers and their families deserve better than this," he said. The steel was imported from Singapore-based company Yongnam. The Andrews government had promised to use overwhelmingly local steel on the projects.

Up to 10 workers on the road project have undergone blood tests for lead poisoning and the consortium said the results were within the normal exposure limit. A project source said the workers were lucky to have worn advanced welding shields, which include an air filter, rather than regular welding shields. The lead is being removed from the undercoat of paint. Minister for Transport Infrastructure Jacinta Allan said it was"completely unacceptable" for the workers to have been exposed to lead. "Whilst I am pleased the strict safety measures picked this issue up, these incidents are completely unacceptable," Ms Allan said.

"I've asked the director-general of the Major Transport Infrastructure Authority to speak to the companies involved to ensure the safety of workers and public." Opposition workplace safety spokesman Nick Wakeling said the government needed to reassure workers on other government-funded projects that "they too are not being exposed to toxic lead from contaminated steel". Transurban’s West Gate Tunnel project is a six-lane roadway that will link the West Gate Freeway in Yarraville to CityLink in West Melbourne. Preliminary works are under way to sink two 90-metre, 4000-tonne tunnel boring machines – at 16 metres high, as tall as a five-storey building – under Melbourne’s west to dig the project. Bella, one of the 4000-tonne boring machines that will create the West Gate Tunnel in Melbourne, is dissembled at a factory in China so it could be shipped to Australia. Credit:West Gate Tunnel Project

For these boring machines to start their work, enormous temporary supports must be built to lower them into place. These supports were being built using the lead-coated steel. West Gate Tunnel project chief executive Peter Sammut said work had stopped after the issue was identified. "Safety is our first priority," he said, Rail Projects Victoria chief executive Evan Tattersall said steps were "under way" to ensure there was no recurrence. He also said safety for workers was its "first priority". A WorkSafe spokeswoman said it was satisfied ''adequate steps'' to control exposure risks had been taken. ''It will continue to monitor the site.'' Lead has been banned as an additive to domestic paint since 2010 but can still be found in trace amounts. Older Australian houses can contain paint with extremely high levels of lead. Leaded petrol was banned in Australia in 2002.

A Yongnam spokesman said it was working with its customers ''to ensure all products fully comply with Australian standards.'' The West Gate Tunnel has been sold as a panacea to the western suburbs’ traffic woes, and as a project that will free up space on the West Gate Bridge. But its city off-ramps will also pour thousands of extra cars into North and West Melbourne, which the city council says will undo decades of work to limit car numbers in those areas. Do you know more? Contact us securely via Journotips