People who have eaten eels and freshwater fish from two South Taranaki streams contaminated by fire-fighting foam are being urged to come forward.

Photo: RNZ / Robin Martin

Elevated levels of PFOS chemicals have been found in mahinga kai in the Ōaonui and Ngapirau streams and the Ministry of Primary Industries has advised people not to gather food from them.

The oil company Shell has admitted contaminating groundwater at several sites in Taranaki using fire-fighting foam banned in New Zealand 12 years ago.

It said it stopped using the foam in March.

The Ōaonui and Ngapirau streams are near the Maui Production Station and the Ōaonui is adjacent to the Hot Fire Training facility run by the Wood Group.

The Ministry for Primary Industries has warned people not eat eels or fish from the Ōaonui at all, and only once a month from the Ngapirau.

Taranaki DHB's Medical Officer of Health Jonathan Jarman wanted to hear from anyone who had been eating eels or fish from the streams.

"It is possible that people have been exposed through the consumption of mahinga kai, through eels and freshwater fish and in combination with the Ministry of Primary Industries we would like to catch up with those people and try to establish their levels of exposure," Dr Jarman said.

PFOS have been on the international chemical hazards list since 2009 and were banned here in 2006. The man-made chemicals can last thousands of years and accumulate in the body. Health concerns have been raised worldwide, though the research into their impacts is inconclusive.

Dr Jarman said the risk grew with the level of exposure.

"It's the dose that's makes the poison so we need to find out just how many eels people have been eating from one of the streams in particular.

"Is it something that people do every day or every week or every month and from that exposure we'll be able to determine risk."

Dr Jarman said the DHB, MPI and the council were taking a precautionary approach and at this stage there did not appear to be an acute health risk in Taranaki.

Climate Justice Taranaki spokeswoman Catherine Cheung said the contamination scare did not surprise her.

"I think they are just a result of the well known self-regulation practices of the industry - the oil industry is known to self-regulate - and also the very poor monitoring and reporting practises of the regulatory authorities."

Ms Cheung believed with the amount of petrochemical activity in Taranaki the problem could be more widespread.

Te Rūnanga Ngāti Ruanui kaiarataki Debbie Ngarewa-Packer said her iwi was still trying to get clarity about the situation at the Rimu production station outside of Hāwera.

She said it was not good enough that waterways were being still being polluted in 2018.

Photo: RNZ / Robin Martin

"We shouldn't be getting surprises like this. We're a first world nation and we should be able to be assured that the practices going around our waters are safe and the life forms in ... the waters are safe too."

Ngāti Ruanui was calling for a full audit of where fire fighting foam has been used, Ms Ngarewa-Packer said.

Taranaki Regional Council said it was considering taking compliance action against Shell and the New Plymouth District Council which owned the city's airport where groundwater contamination had also been found.

It said its investigation was ongoing.