Many residents of contaminated communities near Defence bases, like Katherine in the Northern Territory, are known to carry around high PFAS concentrations in their blood.

The Metropolitan Fire Brigade in Melbourne has funded Macquarie University to conduct the study because of the high PFAS levels in the blood of firefighters.

The firefighters were exposed to the high PFAS concentrations from fire-fighting foam, the same foam which leached off the Tindal RAAF Base into Katherine's drinking water supply which contaminated residents.

A Federal Government inquiry looking into PFAS contamination was given details of the trial among about 300 firefighters at a hearing yesterday.

One Katherine resident today called the move a "Dracula solution".

The Macquarie University's PFAS Clinical Study aims to discover whether donating whole blood every 12 weeks or plasma every six weeks over a 52-week period can reduce PFAS levels in firefighters' blood.

"The Macquarie University is supporting firefighters to find a feasible and practical solution to the occupational hazards of their work," parliament's PFAS sub-committee chair of the Joint Standing Committee on Foreign Affairs, Defence and Trade, John McVeigh said.

"However, this unique study may help all those affected by PFAS, as research into its potential health impacts continues."

No-one is sure how long it takes for PFAS to be eliminated from an individual but most experts say it could take decades.

Australian health experts are also still undecided on whether PFAS causes health problems, although the official advice is to "minimise exposure as a precaution".

"Whilst PFAS levels do appear to slowly drop over time once the source of exposure has been eliminated, their potential adverse health effects indicate the importance of developing an intervention to bring down elevated levels at a faster rate," the university researchers said.

"The trial also includes biochemistry analysis. Biochemistry samples shall be taken at Screening and Week 52 and shall assess the following biomarkers: urea and electrolytes, liver function, lipid levels, full blood exam and thyroid test.

"If whole blood or plasma donation significantly reduces serum PFAS levels, this may inform strategies to reduce the potential health risks associated with occupational PFAS exposure."

The trial takes in about 300 firefighters.

Once tested, the blood is being donated to the Australian Red Cross for use in medical treatments.

Buckets of blood were taken from Katherine residents in 2018-2019 as part of a Federal Government screening program which also included the Defence contaminated areas of Oakey and Williamtown.

Results of the Australian National University trial, believed to be one of the biggest community health screening programs of its type ever undertaken in Australia, have been delayed until next year.

The ANU now wants to collect blood from Alice Springs volunteers to compare with the Katherine results.

Individual test results were described as "scary" by Katherine GP, Dr P.J. Spafford, who collected blood from more than 600 residents under the free government program.

The Macquarie University's PFAS Clinical Study is expected to finish in about a year.