Australia has launched an extraordinary multibillion-dollar lawsuit over widespread contamination of defence sites with “forever chemicals”.

The federal government is suing manufacturer 3M for more than $2 billion to recover costs from per- and poly-fluoroaklyl substances (PFAS) contamination in firefighting foam at 28 defence bases across the country.

3M, an American multinational manufacturing company, is vowing to fight the lawsuit.

The claim, lodged in the Federal Court, alleges 3M withheld information and misrepresented the effects of its aqueous film-forming foam, including environmental risks.

“This is the largest legal claim ever brought by the Commonwealth,” Attorney-General Michelle Rowland said on Thursday.

Recouped money will be used to cover past and future expenses incurred in investigating and managing contamination resulting from the historical storage and use of the foam.

PFAS have been widely used in products such as firefighting foams. Photo: CRC Care

It has already cost Australian taxpayers more than $1 billion to investigate, remediate and mitigate PFAS contamination on defence estates.

“Make no mistake, this legal action against 3M is significant,” Rowland said.

“It is commensurate with a government that’s committed to fighting for Australians and their long-term interests.”

Per- and polyfluoroalkyl substances are a group of 15,000 toxic, synthetic chemicals used for their resistance to heat, stains and grease.

PFAS have been widely used in products including cookware and firefighting foams due to their oil and water repellence and temperature resistance.

While the science around the chemicals is evolving, the federal health department says they are associated with low birth weights in babies and altered levels of hormones.

Specific chemicals such as PFOA and PFOS are linked with an increased risk of testicular and kidney cancer.

3M stressed it never manufactured PFAS in Australia and ceased local sales of the problematic products about two decades ago.

“Despite this, the Department of Defence continued to use PFAS-containing fire fighting foams for nearly two decades longer, as noted in a recent legislative committee report,” the company said in a statement.

“We will defend ourselves against these claims through the legal process.”

Assistant Defence Minister Peter Khalil said the claim was focused on the environmental, economic and cultural impacts at the 28 affected Defence bases.

“We’ve done a fair bit of work on remediating or containing the spread of PFAS, or the plume from spreading beyond the borders of the base,” he said.

“This case is focused on the environmental, economic, and cultural impacts, and the cost of that, that has been incurred by the Commonwealth and Defence in the past and into the future.”

In 2018, the Department of Defence warned locals near the Richmond Air Base to reduce their intake of local fish and eggs after PFAS was found in the groundwater nearby.

A Senate inquiry in November recommended legal action against 3M and said any settlement should be used to fund remediation of contaminated sites.

In its submission to the inquiry, 3M said it had been an industry leader assisting PFAS regulation and were experts at removing the chemicals.

3M Australia is a subsidiary of US global multinational conglomerate 3M Company.

Attempts have been made to contact the company for comment.

-with AAP