Oceana’s billboard about mercury in fish is incredibly irresponsible, given what the scientific community is saying. [“Group to Keep Up Pressure On Publix,” April 3].

Posting seafood warnings in supermarkets is a horrible idea. The FDA’s mercury advisory is only intended for child-bearing women and very small children. Last year, the federal government’s Institute of Medicine warned of a “spillover effect” that would deny non-targeted Americans the health benefits of fish by needlessly scaring them away from the seafood counter.

And even fish-related mercury warnings for pregnant women may soon disappear. A massive U.S. government-funded study published this year in the British medical journal The Lancet concluded that there is no scientific basis for scaring moms-to-be away from seafood. Of the thousands of pregnant women in this well-regarded study, those who ate the most fish – mercury and all – had children with the highest IQs.

Fish is a health food. If anyone is endangering public health, it’s activist groups such as Oceana that give seafood the skull-and-crossbones treatment.