Construction, Mining, Forestry and Energy Union occupational health and safety advisor Darren Kavanagh said an acceptable level of lead contamination in paint was just one percent.

“The fact that their employer Hitachi knew of prior contamination and didn’t tell us about it is a disgrace,” he said.

“Workers are worried, parents are worried and so too are families, as lead contamination can be transported into the home via clothing and work boots.”

However Bluewaters site manager Edgar Coello said workers had no need for health concerns and had been informed as soon as lead was confirmed as being onsite.

“There is a very minimal risk of workers’ exposure to lead or to their health and safety in going about their normal duties,” Mr Coello said. “Tests were carried out to confirm the company’s view that any lead risk was minimal.”

He said all completed health surveillance tests received to date had produced a negative result to lead exposure. He said the primary components contained in the main construction structure at Bluewaters did not contain lead-based material and with the exception of some products such as children’s toys, it was not illegal to use paint products containing lead.

“Only recently has lead ceased to be used in the manufacture of paint,” Mr Coello said.

“It is likely that many houses and industrial plants in the region are painted with lead-based paint.

“Lead is a common chemical occurring in many forms and contained in many materials that occur in everyday life.”

Mr Coello said the project aimed to minimise the amount of onsite material which contained lead as much as possible.

He said equipment found to have been contaminated had either been transported offsite or risks mitigated through appropriate procedures advised by specialists.

“The material containing lead-based paint onsite was used in the transportation of equipment to site,” he said.