The panel, led by NSW chief scientist Mary O'Kane, met for the first time on September 23 to discuss preliminary results from water and fish testing.

It recommended lifting the ban, put in place on September 4, on the sale of oysters from upper Tilligerry Creek commercial oyster farming area, which was done on October 3.

However, fishing from the creek and Fullerton Cove will remain closed until October 31.

"The early test results for some fish species show increased levels of PFOS," Ms O'Kane said.

"As a precaution, the panel has recommended the ban continue until we have a clearer understanding of what the results mean."

The Williamtown Community Reference Group also met for the first time on October 1.

Representatives from Port community action groups, fishermen's co-op and the Worimi Local Aboriginal Land Council have been selected to sit on the panel to provide a voice for affected residents.

Port Stephens MP Kate Washington said her requests to sit as a community representative on the reference group had been ignored.

"My community has a deep distrust of every government agency that is represented on the community reference group, and not without reason," said Ms Washington.

"Whilst there are community representatives who will also sit on the reference group, it shouldn't be their responsibility to represent all the affected residents.

"I was elected by the community to represent their interests; they come to me for answers and with practical solutions.

"If I'm not on the panel, how does the broader community have any input into the process?"

Ms Washington was also calling on the NSW Department of Premier and Cabinet to appoint an independent chair to head the community group, which will meet again on October 8.