This is a pdf put out by the epa that breaks down fish consumption by bodies of water. Some very good info for anyone wondering toxic levels in fish.
http://www.epa.state.oh.us/portals/35/fishadvisory/fishadvisory_pamphlet.pdf
http://www.epa.state.oh.us/portals/35/fishadvisory/fishadvisory_pamphlet.pdf