Fish Store Toxins

A type of fish in the Hudson River has a unique way of resisting the river's pollutants:

"Instead of getting sick from dioxins and related compounds, Atlantic tomcod harmlessly store these poisons in fat."
- Mutant Fish Safely Store Toxins in Fat, Wired Science, February 18, 2011

Good for the tomcod, bad for us:

"Each bite of tomcod that a predator takes will move a potent dose of toxic chemicals up the food chain — eventually into species that could end up on home dinner tables."

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On a related note, our plastic waste has become animals' dinner, with similar consequences to the food chain:

"Some types of plastic begin to break down in the ocean within one year, releasing potentially toxic bisphenol A (BPA) and other chemicals into the water.
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Both BPA and components of styrene trimer have been shown to disrupt hormone function and cause reproductive problems in animals.
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Plastic poses the biggest threat to marine animals that confuse garbage with dinner and end up digesting large quantities of polystyrene.
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“Every size of organism, every creature in the food web in the ocean, from the smallest filter feeders to the largest whales, is consuming plastic,” says ocean researcher Charles Moore."
- Toxic Soup: Plastics Could Be Leaching Chemicals Into Ocean, Wired Science, August 19, 2009

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And now ... The USDA's new Dietary Guidelines recommend a higher intake for seafood:

"The Dietary Guidelines for Americans, 2010 includes a new quantitative recommendation for seafood intake. An intake of 8 or more ounces per week (less for young children), about 20% of total recommended intake of protein foods of a variety of seafood is recommended."

I'm not sure how to reconcile the two. Maybe eat fish lower on the food chain. None of this takes into account the widespread overfishing and depletion of fish stocks. What was the USDA thinking?
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