Dear Dave: 
 

I am writing the expert for a answer regarding salmon.  I was listening to a food expert that said you should only eat wild salmon and not farm raised  because it is much healthier for you.  I went to the grocery for wild salmon and they couldn't tell me if it was wild or not so could you explain it to me in laymans terms.  
 

Beth

Well, Beth, he may be an expert on food, but certainly not on fish!   The marketing war the wild-caught fishery industry has waged on aquaculture (since salmon farming has taken over 50% of their market share) has produced an enormous amount of misinformation heaped on the general public.  An anti-aquaculture group gave 2 million dollars to some researchers a few years ago, and they included more money for a public relations campaign than most scientists get for a whole grant.  So when in 2004 they announced their results of sampling environmental contaminants (pcb's) of wild and farmed salmon, they hit the media in an unprecedented campaign that left the public food agencies (from the FDA to the American Heart Assn.) unable to counter the nonsense of their "conclusions".  They proclaimed that farmed salmon had "dangerously higher" levels of contaminants, when in fact both were healthly and 200x lower than the safety standards set by the FDA.  The only reason  that any minute traces of contaminants were found in the farmed salmon, is that they are raised in pens along the coast, and they pick up these traces from the open environment (unlike our inland fish, which have no detectable levels!)  The biggest boondoggle of all is the way in which that "research" was conducted and how they chose their sample locations.  The highest levels were found in Europe, where persistent industrial contamination is worse, and not in Canadian or Chilean farmed-salmon, but had they sampled the wild Copper River salmon (which they did not), they could have found levels 10x higher than the safety limits in what is considered the most premium wild-caught salmon.  In fact, the level of pcb's in this salmon increases as it migrates up its home stream, since the contaminants are stored in fatty tissues, and becomes more concentrated as they lose muscle mass on their journey.  It is already a concern in environmental science circles that migrating wild salmon are acting as pcb-pumps and transporting coastal pcb's into the upper mountain streams, and as the contamination increases, this may be one of the reasons for the poor survival of the salmon eggs and fry that are extremely sensitive to any form of pollution.
    Health professional are greatly concerned about the damage that this misinformation may have on public health because of people fearing one of the most healthy foods available to them (one of the top 10 "super foods" along with whole grains and berries).  Recent research has also shown dramatic health and cognitive improvements in children whose mothers ate weekly amounts of oily fish like salmon and trout. 
    In all, it has been very frustrating for aquaculturists who are trying to produce a wholesome product for the market place, although I am confident that the truth will come out in the end.
---Dr. Dave., Freshwater Farms of Ohio

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