August 30, 2015
Richard Ellis on ‘Diagnosis: Mercury’
Posted on Nov 28, 2008
In her book, Dr. Hightower reports that albacore tuna has three times the mercury content of “light meat” tuna, which is skipjack, a small tuna canned by the billions and found on supermarket shelves around the world. “White meat tuna” sounds somehow better than ordinary “light meat tuna,” but in fact, it contains more mercury. From the EPA Web site:
“Outbreaks of methylmercury poisoning have made it clear that adults, children, and developing fetuses are at risk from dietary exposure to methylmercury. During these poisoning outbreaks, some mothers with no symptoms of nervous system damage gave birth to infants with severe disabilities and it became clear that the developing nervous system of the fetus may be more vulnerable to methylmercury than is the adult nervous system. Mothers who are exposed to methylmercury and breast-feed their babies may also expose their infant children through their milk.”
There are no warnings on cans of tuna, and hardly any in restaurants. Of course, the absence of certain fish species on restaurant menus would serve as an implicit warning, but how is the customer to know that? Because of overfishing, Caroline Bennett of London’s Moshi Moshi restaurant chain serves no bluefin in her conveyor-belt sushi bars—and says so.
Thanks to the marine conservation group Oceana, warnings are beginning to appear in supermarkets. Oceana “campaigns to protect and restore the world’s oceans by winning specific and concrete policy changes to reduce pollution and to prevent the irreversible collapse of fish populations, marine mammals and other sea life.” Its current projects include halting the slaughter of sea turtles, stopping offshore drilling, banning Mediterranean drift-netting, protecting sharks from finning, saving bluefin tuna, and encouraging supermarkets to post signs warning of the dangers of mercury in fish.
According to Oceana’s Jacqueline Savitz, “We now have convinced 36% of major grocery stores in the U.S. to post signs.” Among the chains now posting signs that contain the FDA warnings are Trader Joe’s, Whole Foods, Kroger, Harris Teeter, Costco, Albertson’s (SuperValu owned) and Safeway, and they are working on Wal-Mart, the world’s largest publicly owned corporation. A typical sign, posted adjacent to the canned fish display shelves, reads:
Notice that there is no mention of mercury, the reason for the warning in the first place. Is this because the supermarkets don’t want to frighten their customers? Because the fishing industry doesn’t want any of their products to be associated with mercury?
Because everyone knows that mercury is poison, one would assume that there would be some sort of guideline posted somewhere about what a “safe” level might be—assuming there was a safe level. But as Dr. Hightower learned, the “guidelines” are often vague, inconclusive and largely unavailable to the fish-consuming public. When Hightower questioned a research scientist at the California Department of Public Health, she was told that “a blood mercury level of 200 mcg/l was OK in adults.” That was four to 10 times what she had been seeing in her patients, and 40 times the ceiling recommended by the EPA.
When Dr. Hightower looked up mercury poisoning in a medical textbook, she learned that the symptoms included insomnia, nervousness, mild tremor, impaired judgment and coordination, decreased mental efficiency, emotional liability, headache, fatigue, loss of sex drive and depression, as well as severe paresthesias (prickling or tingling sensation of the skin), trouble speaking, trouble walking, tunnel vision, hearing loss, blindness, microcephaly (small brain size at birth), spasticity, paralysis and coma. In the “Cecil Textbook of Medicine,” she found that the “reference range”—what is considered the maximum acceptable to maintain good health—was less than 50 mcg/l for whole blood. No further information as to diagnosis, treatment, prognosis and so forth was included in the textbook.
“Diagnosis Mercury” is not only about Dr. Hightower’s patients. It is about mercury poisoning in general. In the late 1950s, in Minamata, Japan, 1,700 people died and thousands more showed aggravated symptoms of mercury poisoning after eating fish from the bay where the Chisso chemical plant was spewing mercury effluent into the water. Originally published in Japanese in 1977, Akio Mishima’s “Bitter Sea: The Human Cost of Minamata Disease,” was reissued in English in 1992. In the introduction, we read:
“As a result of the bay’s pollution with toxic organic mercury, many people were stricken with a terrible syndrome in the 1950s. Minamata disease, as it came to be known, is characterized by numbness of the extremities and the area around the mouth, constriction of the field of vision, loss of hearing, motor and speech disorders, loss of muscle coordination, convulsions, and sometimes mental aberrations, People congenitally afflicted with the disease are often mentally retarded.”
“Bitter Sea” incorporates photographs of the plant, the victims and the protesters, which serve as a painful testimony to the horrors of mercury poisoning. In 1972, more than a decade after the poisoning of Minamata Bay had been recognized, American photographer W. Eugene Smith (1918-1978) went to Japan to document the gruesome story of Minamata Bay. Although he succeeded—his photographs are heartbreaking—goons from the Chisso Chemical Co. beat him so severely that he was partially blinded and never fully recovered his sight.
Between 1962 and 1970, two communities in northwest Ontario, Canada, were warned that fish caught in the English-Wabigoon river system had record-high levels of mercury from a chemical plant up the river. By the mid-1980s, local Indian tribes received a compensation package of almost $17 million from the Dryden Chemical Co. and the provincial and federal governments. They are still advised not to eat fish from the river. Almost everybody agrees that mercury is bad for your health.
After reading “Diagnosis Mercury,” I have concluded that there really is no “safe” level of mercury, and I’m going to stop eating tuna. Why would anyone want to continue ingesting such a deadly substance? Let me repeat the symptoms of mercury poisoning: insomnia, nervousness, mild tremor, impaired judgment and coordination, decreased mental efficiency, emotional liability, headache, fatigue, loss of sex drive, and depression … severe paresthesias, trouble speaking, trouble walking, tunnel vision, hearing loss, blindness, microcephaly, spasticity, paralysis and coma.
I’m going to tell my children to stop eating tuna, and anybody else who will listen. It’s not likely that the Japanese, who buy and consume thousands of tons of bluefin tuna annually, will be scared off by mercury warnings, but it is fantastic (as in “fantasy”) to think that if enough people stop eating tuna, the fishermen would not be able to sell their catch, they would stop fishing, and the endangered bluefin would be saved from extinction. Maybe this is just a mercury-induced hallucination (until very recently, I’d eaten as much tuna as anyone), but I hereby endorse the publication and frightening conclusions of “Diagnosis Mercury.” I am tempted to quote the entire book, but the best I can do is recommend that you read it.
Richard Ellis is a celebrated marine artist and the author of more than a dozen books. He was written and illustrated articles for numerous magazines, including Audubon, National Geographic, Discover, Smithsonian and Scientific American. His newest book, on the plight of the polar bear, will be published by Alfred A. Knopf in 2009.
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