– flounder
– hake
– haddock
– herring
– salmon
– trout
– whitefish
– pollock
– sardines
While all of these fish are low in mercury, NRDC notes that farmed salmon should be avoided because it can contain high levels of another chemical with serious long-term health effects — PCBs (Polychlorinated biphenyl). The NRDC also recommends avoiding haddock and flounder because these fish are low numbers due to extensive fishing.