Testing is underway at an Adelaide fire station after staff were found to have concerning blood levels of a chemical used in firefighting foam.
The Metropolitan Fire Service recently conducted more than 200 tests on past and present staff, with nine firefighters at the Largs North station returning concerning samples.
The MFS conducted further testing at the Largs North station on Tuesday to determine the possible cause of the PFAS chemical exposure, which could be from food produced in a vegetable garden on the site.
PFAS chemicals were found in firefighting foams previously used by the MFS but the service's scientific officer, Krystle Mitchell, said the source could lie elsewhere.
"We do know that (nearby) fuel storage facilities in the past have used the foam," she said.
"At the moment we're testing as much as we can at the station to rule out anything at the station itself."
Ms Mitchell said the organisation stopped using dams at the Adelaide and Oakden fire stations because of their high PFAS levels.
She said if the Largs North station was the source, the MFS would need to remediate and the site could be temporarily closed.
The PFAS chemicals have been linked to cancer in studies overseas and have been the subject of a recent inquiry into their use on air force bases in Australia.
"It would concern anyone if they had an above-average level in their blood," Ms Mitchell said.
She said there were no known clusters forming at stations outside Largs North but encouraged concerned firefighters to have their blood taken.
The investigation comes as the Department of Defence released details of PFAS contamination at the RAAF base at Edinburgh in Adelaide's north.
It said in samples taken on-base, PFAS had been detected in soil, surface water and shallow groundwater at "above the human health guidance values", with stormwater and shallow groundwater identified as pathways for PFAS movement off the base.
In samples taken off-base, PFAS concentrations above the human health guidance values were limited to shallow groundwater and fish and yabbies within a local wetland.
The results from samples taken at private properties were below human health guidance values.
