'Higher than expected' levels of PFAS have been confirmed in the blood samples of dozens of islanders living in Jersey.
Government-backed testing was carried out on 72 people from 31 addresses very close to Jersey Airport where the toxic chemical leaked from in 1991.
It came from fire-fighting foams which were used at the airport for training.
The foams spread into nearby streams, ponds and boreholes, resulting in high concentrations of PFAS in a small number of people's drinking water.
High levels of PFAS have been linked to cancer, bowel disease and birth defects - however, Jersey's Director of Public Health insists more research is needed to establish exactly how PFAS affect the body.
The 72 islanders were tested between June and August this year, and elevated levels of PFAS were discovered in "a reasonable proportion" of them.
Jersey's Minister for Health and Social Services, Deputy Karen Wilson, said: "It was announced in early February that PFAS blood testing would be available for Islanders affected by the historic plume at the airport.
"I fully understand that levels of PFAS have been an area of concern for Islanders who lived or worked the plume area for some time, who drank water from private supplies, and we are taking these concerns seriously.
"It is extremely difficult to interpret results of blood tests for PFAS as there is not an internationally accepted way of interpreting them. It is also currently impossible to assess the impact on an individual's health.
"The difficulties in interpreting these results will no doubt continue to cause uncertainty; however, the Government is committed to doing all we can to develop our understanding and continue conversations with Islanders as our knowledge grows."
The testing cost the government approximately £100,000.
Islanders who had their blood tested will now be invited to meet the Chief Minister, Deputy Kristina Moore, Health Minister, Deputy Karen Wilson and representatives from Public Health, to discuss results from the blood tests.
The government is also now going to set up a scientific advisory board to look at the health implications and advise on the next steps for those affected - including when they should be re-tested.
However, there is no guarantee this will be established by the end of the year.
Professor Peter Bradley explained: "Individuals who are experts in this field are hard to find. But we do know a couple of them and I would expect the panel to be set up by early next year."
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