Fishing on wharfs on the f3 line

Caught the ferry with my family the other day and saw a lot of people fishing between the city and Parramatta on the Parramatta river on wharfs etc.

I thought eating fish west of the harbour bridge was poisonous because of the chemical spillage decades ago around Sydney olympic park etc.

While some people looked to just be casual fishing or catch and release i saw others that look like they were fishing to eat.

Is not eating catched fish still a thing or is it safe to do now days?