In addition to mercury, some seafood contains dangerously high levels of dioxins, polychlorinated biphenyls (PCBs), pesticides and other not-so-tasty contaminants.
And there are concerns over aquaculture practices that include heavy antibiotic use, habitat destruction like clear-cutting of coastal mangrove forests, and crowded fish pens that spread disease. Fortunately, sustainable seafood is easy to find.
Overfishing: Seafood With a Side of Guilt
It's hard to ignore the problem of overfishing and the serious depletion of fish stocks around the world. Some popular fish like Atlantic cod, orange roughy and Chilean sea bass are in danger of a global population collapse or extinction due to industrial fishing techniques.
The good news for us seafood lovers is that a dish of fish remains an excellent, affordable source of protein and critical nutrients like omega-3 fatty acids. It's low in fat, easy to prepare and tastes wonderful. Some farm-raised fish and shellfish, like catfish, tilapia, scallops and mussels, are healthy to eat and are usually raised in sustainable, low-impact environments. And there are safe seafood choices for pregnant women, so aquavores can still enjoy a great meal without a side dish of fear or guilt.
A number of environmental organizations have developed tools to help consumers make smart, sustainable seafood choices. (Forgive me if I hesitate to use the phrase "green seafood").
Avoiding Mercury in Fish and Other Hazards
I'm not good at memorizing lengthy lists of safe and unsafe seafoods -- nor am I good at remembering to pack a list of seafood recommendations in my wallet every time I leave the house. That’s why Blue Ocean's text-message service is the greatest seafood tool since the shrimp fork. Just send a text to 30644; start with the word "Fish," followed by the name of whatever you’re thinking about ordering. In seconds, Blue Ocean will respond with a brief message about that fish's health status and environmental impact.
For example, when I sent the text message "Fish chilean sea bass," Blue Ocean gave me the following response: "(RED) significant environmental concerns; problems include illegal fishing and high bycatch; HEALTH ADVISORY: High Mercury; try striped bass or pacific halibut instead." You can also download a copy of their seafood guide onto your cell phone to view anytime. (Finally, a good reason to use your cell phone at the dinner table.)
More on Sustainable Seafood
If you'd like more comprehensive information, the Environmental Defense Fund has done exhaustive research into seafood, aquaculture and the potential health impacts of fish and shellfish. In addition to a mobile phone guide, the EDF also has divided the world of seafood into three categories -- Eco-Best, Eco-OK, and Eco-Worst -- that make buying and ordering seafood easy.
Other groups, like the Monterey Bay Aquarium and the Marine Stewardship Council, have similar tools and lists. Whichever you choose, remember that buying sustainable seafood and ordering it in a restaurant doesn't have to be a difficult process. Order up, and enjoy a delicious meal without worrying about your health or that of the planet. Bon appetit!