More will be known about the PFAS chemical exposure of Katherine than any other contaminated community in Australia.

Yet residents may have to wait two or more years to learn how bad the contamination is.

Individual test results have already been described as "scary" by the town's GP, P.J. Spafford, who has taken blood from more than 600 residents so far under a free government program in response to the PFAS emergency.

Test results have been provided to individuals but whether the town is in the grip of a community-wide crisis won't be known for years.

Existing and former residents have until the end of the month to have their blood tested in one of the biggest community health screening programs of its type ever undertaken in Australia.

The Australian National University has been given the job to launch a blood serum study to compare Katherine's blood PFAS levels to non-contaminated areas in similar townships in Australia.

The university is doing the same for Williamtown and Oakey, although hundreds more residents volunteered for the blood tests in Katherine than those two areas combined. 

More blood will have been drawn from Katherine than any other contaminated community in Australia by the end of the month when the free testing ends.

"The overall results of the blood serum study and the cross sectional survey will be summarised for each of the three communities: Williamtown, Oakey and Katherine," an ANU spokeswoman said.

"The PFAS Health Study team will provide a report on these parts of the study to government in the middle of 2020 and we will provide summary reports to residents of the three towns after that time."

That response was later qualified to say, the government would be given the Katherine results, and it would be up to them to time the release of them.

Dr Spafford is unable to comment at the collector of the blood for the government, but was able to respond as a spokesman for the Coalition Against PFAS group.

"The very fact 600 people have voluntarily sought blood tests in Katherine shows you the level of concern in the community," Dr Spafford said.

"The Department of Health has confirmed they won't even look at the results but sit and wait for an academic study that is at least a year away from being completed.

"So how can the Government make any comment or provide any advice without any knowledge of the results? And, as part of the Australian Government, presumably this includes the Department of Defence."

A worried Katherine father supplied the Katherine Times his son's test results early last year.

The 11-year-old's "allowance" for PFAS at his was 18 nanograms per millilitre while the boy's result was 102.

The Katherine Times has been supplied results as high as 200 but only the government will have this a community-wide knowledge.

"We don't know what to do," the Katherine father of the 11-year-old said.

"We are holding our breath and hoping he does not get sick."

Dr Spafford has warned PFHxS, part of the PFAS family of chemicals, is the most worrying of the current Katherine results.

The government advised those taking part in the blood tests that "testing currently does not indicate the likelihood of disease or otherwise in that person".

But it also warns patients with high results to avoid future PFAS exposure.

More reading:

Katherine's PFAS timeline

"PFHxS and other PFAS's (excluding PFOS and PFOA) are reported in the blood test results for research purposes," the health department has told Katherine Times.

"PFHxS blood levels are not predictive of health problems in individuals. There is currently no consistent evidence of PFHxS resulting in specific health impacts."

Yet this advice is rapidly changing now alarm over PFAS has been raised across the world.

The ANU is inviting people to take part in another PFAS survey.

The survey is part of the government-funded university PFAS Health Study to ask participants to provide information on potential exposure to PFAS, existing health conditions and any concerns about their health in relation to PFAS exposure within their community.

The survey will be linked to PFAS blood test results.

In its preamble to the health study the ANU says "studies have found evidence that higher levels of PFOS or PFOA in a person's blood can lead to higher blood cholesterol levels; there is also evidence that exposure to PFAS may lead to a decreased response to some vaccines, may be associated with reduced kidney function, and may be associated with some cancers, particularly testicular and renal cancer".

The survey will begin in mid-2019, with analysis of the responses due to the Department of Health in mid-2020.

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