Every time I think we have a path to clarity about fish–such as in which fish to eat–a new, troubling report comes out. This one sounds like a planet: Yes, Mercury is back into the headlines once again. Maybe it never left, but the latest study indicates that if we try to eat fish, thinking that is a healthy alternative to beef, and we try to focus on the sustainable variety, we are still left with a crisis. The focus again is on
mercury contamination. Not just a single kind of fish, but it seems almost all fish.
Once again there is a handy fish guide (A Mercury Calculator) directing us to safety and telling us what to avoid. The big question is simply: Is fish safe? Well it depends. Assume there is mercury contamination present in all US-water based fish. Then decide if you are asking about a young child, a pregnant woman, or a healthy adult. Recognizing that some fish contain less mercury than others and some should be avoided all together helps minimally. You need to know which fish to eat; some, such as canned light tuna, you can have multiple helpings of each week. One that is particularly high in contaminants is swordfish, a fish small children and women of child-bearing age should avoid altogether. The EPA even has this “One Fish…Two Fish” poster available as a reminder.
The most recent announcement from the US Geologic Survey says mercury contamination is higher than expected and almost impossible to avoid.
Know what you eat. It just gets harder to find safe, healthy foods.
A handy pocketsize guide from the 
We’ve all been in the situation where we ask the purveyor, fish counter person: When did that piece of fish come in? How many times have you heard the answer: Just this morning. Or, maybe they say, last evening. Our suspicions run to the top burner as we are never certain. Oh, yes, there are obvious eye tests of freshness as in color, shape, and form. Some people even like to touch the fish to test its firmness and maybe even smell it. Nothing holds a candle to the newest advance that promises greater reliability.