More than 600 residents of Katherine provided their blood more than two years ago to check their levels of PFAS contamination.

The Federal Government has paid the Australian National University $2 million to do the testing and collate the results from Katherine, Oakey and Williamtown in a report delayed until some time next year.

Now researchers are asking hundreds of people from Alice Springs to give up their blood so they can compare the results with Katherine.

A similar call has made made the Dalby and Kiama/Shellharbour areas to have a free blood test and complete a survey to help better understand the health effects of PFAS contamination in their areas.

The blood specimens will be tested to measure PFAS levels and other blood chemicals linked to blood fats (like cholesterol) and others that show how well the liver, kidneys, and thyroid are working.

Overcoming weeks, invitations from Services Australia will be sent to randomly selected residents in Alice Springs.

ANU principal investigator Professor Martyn Kirk has said Katherine needs a "comparison community".

He said ANU wants to find about 500 willing volunteers in Alice Springs to provide blood so it could be Katherine's "comparison".

He said the ANU was confident its study would be complete by the middle of 2021.

The invitation will include information about the study and ask invitees to contact the PFAS Health Study Team at ANU if they would like to participate.

PFAS chemicals have been manufactured since the 1950s and are used in a variety of consumer products, including non-stick cookware, waterproof clothing, and fabric stain protection.

The chemicals last for a long time in the human body.

The environment around the towns of Oakey, Katherine and Williamtown has been affected due to the historic use of fire-fighting foams that contained PFAS.

Members of the Oakey, Katherine and Williamtown communities have been potentially exposed to PFAS through the consumption of contaminated water, and possibly from eating some locally grown foods.

Initial results of blood testing done by Dr P.J. Spafford for the government found at least some Katherine residents with high concentrations of PFAS in their blood.

The ANU is conducting the PFAS Health Study, which is investigating whether exposure to these chemicals and disease rates are higher in Oakey, Katherine and Williamtown compared with Shoalhaven Dalby, Alice Springs and Kiama/Shellharbour.

Study lead, Professor Martyn Kirk, said the study is important because it will give a more complete picture of PFAS exposure in Australia.

"We will use the information from people in the Shoalhaven, Kiama, Dalby, Alice Springs and Shellharbour areas to understand exposure in areas where PFAS hasn't contaminated the environment," Professor Kirk said.

"We want to find clear answers about the health effects of PFAS exposure," he said.

The ANU announced in June its study would now not be complete until next year because of COVID-19 delays.

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