Charlie the Tuna was a cartoon mascot created in the 1960s for StarKist Tuna by the late Tom Rogers. An arrogant fish who wore coke-bottle glasses and a Greek fisherman’s hat, Charlie contended that he would be perfect representative for the company because he had “good taste.” But in every commercial Charlie was rejected by StarKist, with the announcer saying to the effect, “Sorry, Charlie – StarKist doesn’t want tuna with good taste, it wants tuna that tastes good!” Today, however, the overall quality of tuna is such that Charlie may indeed be good enough.
Although I am a big fan of seafood, especially small cold water fish such as herring and Arctic char as they tend to provide the best sources of omega-3s, I have never been a fan of tuna. All tuna contains toxic levels of mercury. Mercury is a metal that can cause numerous medical problems, including damage to the brain, kidneys and endocrine system.
The worst case of mass mercury poisoning occurred in Minamata Bay, Japan. From 1932 to 1968 the chemical factory of the Chisso Corporation dumped an estimated 27 tons of mercury into Minamata Bay and the Shiranui Sea. By March 2001, 1,784 people in the local area had died of mercury poisoning and thousands of children had been born with brain damage. To date, Chisso has provided more than 10,000 people with financial compensation from this disaster, and the claims are still coming in.
One source of mercury is coal-burning power plants, which produce mercury emissions that pollute water sources. As every kid knows by watching the shenanigans of Sheldon J. Plankton on the SpongeBob SquarePants show, microorganisms convert mercury to methyl mercury, a form of mercury the body easily absorbs. The microorganisms are consumed by plankton, which are consumed by small fish that in turn are eaten by larger fish. Thus, the larger the fish, the more likely it will contain contaminants such as mercury – Bluefin tuna can weigh more than 1,000 pounds. In fact, the French nickname for tuna is "la poubelle de la mer," which means "the garbage can of the sea."
Regarding fish oil supplements, to avoid poisoning from mercury, as well as from other toxins, those who produce fish oil need to choose the fish of origin wisely. Some important factors in the quality of fish oil are the type of fish used to make the oil, the size of the fish (i.e., its position on the food chain), its fat content and where the fish were caught. For example, avoid farmed fish from Europe. Also, compared to wild salmon from Canada, farmed salmon from British Columbia has been found to contain as much as six times the levels of the potentially cancer-causing substance called polychlorinated biphenyls (PCBs).
But let’s not let tuna off the hook yet. Tuna can be contaminated by scombrotoxin, a common type of food poisoning that within 30 minutes after ingesting can cause symptoms such as cramps, nausea, diarrhea, palpitations, dizziness, skin flushing, and throbbing headaches. If tuna is stored above 60 degrees after being caught it can release this toxin – and unfortunately cooking does not resolve the problem. Nearly 300 cases of scombroid poisoning have been traced to tuna since 1990.
Also, earlier this year, an outbreak of salmonella across the United States was traced to yellowtail tuna processed in India, resulting in nearly 60,000 pounds of the fish being recalled. This was a recent report put out by the Center for Disease Control: “A total of 390 persons infected with the outbreak strains of Salmonella Bareilly (376 persons) or Salmonella Nchanga (14 persons) have been reported from 27 states and the District of Columbia.” The report also noted that 47 of these individuals were hospitalized, but no deaths were reported.”
Finally, there’s the issue of radioactive tuna. Seriously. Traces of nuclear radiation from the Fukushima power plant that was damaged by a tsunami were found in Bluefin tuna caught off the California coast. More specifically, small amounts of the radioactive elements cesium-137 and cesium-134 were detected in 15 tuna caught near San Diego in August 2011, which was just four months after these chemicals were released into the water from the power plant in Japan. The amount of radioactive cesium was measured to be 10 times higher than found in fish caught on the California coast prior to the accident.
To answer the question, “Is seafood safe?” The best answer would be “Some of it, but definitely not tuna.” You should avoid imported fish as about half of all illness caused by imported foods involve fish, and stick to smaller types of fish. And when shopping for a fish oil supplement, invest in quality products from trusted brands. Sorry, Charlie!