I love sushi – so the latest news on the health risks associated with consuming tuna is overwhelming.
When you sit down in front of a plate of sushi, or more correctly in a plate of sashimi (raw fish), the presentation is generally reliably appetizing – fish sliced with vinegar rice carefully rolled in fragrant nori sheets. Of course, no serving of sushi would be complete without a side of bright green wasabi, sometimes referred to as “Japanese horseradish.”
Oddly enough, the term sushi doesn’t actually refer to the fish itself. In Japan, the term means “snack” and refers to rice. Sushi, taken to mean raw fish, is a purely Western adaptation.
The bad news for sushi enthusiasts is that alarm levels are being raised about mercury in tuna. This is a concern that should also be shared by people who enjoy canned tuna.
The problem is, eating tuna is a bit of a shit. There is no way to tell if the tuna you are eating contains high or low levels of mercury. Most of the fish we eat arrive at the table untested – both by federal authorities and retailers. The other worrisome concern is that there is virtually no way of knowing where the fish you are eating came from. When he crossed the oceans, he was manipulated by several agents on his way to your home or restaurant. No documentation is available detailing the point of origin or the time elapsed between the date the fish were caught and their arrival on your plate.
Some waterways are more contaminated than others. Mercury enters water most often through the combustion of fossil fuels, and once in the water bacteria convert it into toxic methylmercury. Small fish readily absorb methylmercury. Mercury becomes more and more concentrated as it moves up the food chain. When absorbed by large predatory fish like tuna, there is no way to remove it from the flesh of the fish.
Pregnant women should be most careful about the amount of tuna they consume. The fetus is particularly vulnerable to contamination. Researchers have linked mercury exposure in pregnant women to subsequent behavioral disturbances in their children. The FDA warnings include other types of fish as well. Women of childbearing age and young children should get rid of sharks, swordfish, king mackerel and tilefish. FDA guidelines recommend no more than 12 ounces of seafood per week for people in this vulnerable group – with no more than 6 ounces of tuna.
How will the fear of tuna impact the sushi industry? Already European sushi bars and restaurants are giving the thumbs down to bluefin tuna and experimenting with other tuna species. Some innovative chefs are even ready to experiment with whale and horse meat.
The greatest concern from a consumer perspective is the lack of any clue that would reliably inform them of the toxic levels in the fish they consume. This “unknown factor” makes eating fish a bit risky. This is why it is wise to pay close attention to the amount and type of fish eaten over a given period.