Photo: Water from the Katherine River makes up more than 80pc of water supplied by the Power and Water Corporation. (ABC News: Sally Brooks) Katherine residents are being warned not to eat local seafood and other home-grown produce after an interim report into PFAS contamination identified them as potential health risks. The Department of Defence released details of an interim human health risk assessment for the Northern Territory town on Monday outlining potential exposure pathways to the community. Most of the town is in the investigation area. The chemicals, an ingredient in firefighting foam once used at the nearby Tindal RAAF Base, have seeped into Katherine's bores used for drinking water and irrigation. The interim report said initial findings indicated a number of activities could pose a risk to residents: Drinking contaminated bore water or water from the Katherine river downstream of the Stuart Highway Eating eggs from poultry that have been watered with contaminated bore water Young children eating large amounts of fruit and vegetables in the dry season that have been irrigated with contaminated bore water Eating seafood from Tindal Creek and Katherine river, including as far south as the Daly river Swimming in pools with bore water above recreational values "We did find that in the fish samples that we've taken they have triggered what they call the trigger values in the food standard Australia and New Zealand thresholds," Steven Grzeskowrak from Defence said. "That means it's appropriate to start looking at limiting intake of, in this case, fish from Katherine river." Photo: Many people catch black bream and cherabin from the Katherine River and surrounding waterways. (Supplied: Chaoshu Zeng) The trigger value for PFOS in fish flesh is 5.2 micrograms a kilogram and is based on a child between two and six years old eating 500 grams of fish a week. Compared to the trigger value, barramundi that were tested returned between 12 and 42 micrograms, up to six times the safe level. Cod and catfish contained between 6.2 and 88 micrograms, up to 17 times the value. Other fish had the broadest range, between 9.5 and 350, a maximum of 70 times the