Mercury Myths

[SportFishStaff]

Mercury Myths

1. Myth: The amount of mercury in our environment (and in the fish we eat) is dangerously increasing.

The truth: There's considerable evidence that the amount of mercury in fish has remained the same (or even decreased) during the past 100 years.

One team of researchers from Duke University and the Los Angeles County Natural History Museum compared 21 specimens of Atlantic Ocean blue hake preserved during the 1880s with 66 similar fish caught in the 1970s. They found no change at all in the concentration of mercury.

In another study, Princeton scientists compared samples of yellowfin tuna from 1971 with samples caught in 1998. They expected to find a mercury increase of between 9 and 26 percent, but they found a small decline instead.

And in a unique experiment, curators of the Smithsonian Institution tested tuna samples that were archived between 1878 and 1909, and compared them with similar fish tissue from 1971 and 1993. They found significantly less mercury in the more recently caught fish. In some cases, the difference was more than 50 percent.

There's even some evidence that human beings are exposed to less mercury today than in the past. Alaska's Public Health Department, for example, reports that when the hair of eight 550-year-old Alaskan mummies was tested for mercury, the results showed levels averaging twice the blood-mercury concentration of today's Alaskans.


2. Myth: Mercury in fish presents a serious health risk to Americans.

The truth: The best science suggests that the tiny amounts of mercury in fish aren't harmful at all. A recent twelve-year study conducted in the Seychelles Islands (in the Indian Ocean) found no negative health effects from dietary exposure to mercury through heavy fish consumption. On average, people in the Seychelles Islands eat between 12 and 14 fish meals every week, and the mercury levels measured from the island natives are approximately ten times higher than those measured in the United States. Yet none of the studied Seychelles natives suffered any ill effects from mercury in fish, and they received the significant health benefits of fish consumption.

In November 2005, The American Journal of Preventive Medicine published new research from Harvard University that put the risk from fish-borne mercury in its proper context. Dr. Joshua Cohen, the study's lead author, summed up the issue for MedScape Medical News: "[W]e're talking about a very subtle effect of mercury … changes that would be too small to measure in individuals."


3. Myth: The health risk from mercury outweighs the health benefits of eating fish.

The truth: The opposite is true. Omega-3 fatty acids found in fish can decrease the risk of heart attacks, strokes, kidney disorders, Alzheimer's disease, breast cancer, prostate cancer, uterine cancer, rheumatoid arthritis, type-2 diabetes, low birth-weight, post-partum depression, and pre-term delivery. The bad news? Partially because of the health scares surrounding mercury, Americans' intake of Omega-3 acids is 3 to 6 times lower than the levels recommended by the National Institutes of Health and the American Heart Association.

Harvard's Dr. Eric Rimm told The New York Times in 2004: "The message of fish being good has been lost, and people are learning more about the hypothetical scare of a contaminant than they are of the well-documented benefits."

A 2005 study published in Archives of Neurology showed that elderly people who eat fish at least once a week can slow their rate of mental decline by between 10 and 13 percent. Research published in the same journal in 2003 found that adults who consume fish once or more each week have a 60 percent lower risk of developing Alzheimer's Disease. A 2004 study of children in Bristol, England showed that the children of pregnant women who consumed high amounts of fish scored higher on mental development tests. That same study found "no adverse developmental effects associated with mercury."

And studies published in the November 2005 American Journal of Preventive Medicine found that even eating small amounts of fish each week can result in a 17 percent lower risk of heart disease, a 12 percent lower risk of stroke, and (when eaten by pregnant women) a modest 1/8-point increase in children's IQ.

When activist groups like Friends of the Earth or the Sierra Club attack fish because of the theoretical health risks from trace amounts of mercury, they completely ignore the very real positive health impact of eating fish.


4. Myth: High fructose corn syrup contains traces of mercury that present a unique health risk to Americans.

The truth: The mercury-in-corn-syrup myth stems from a deeply flawed January 2009 study by the Minnesota-based Institute for Agriculture and Trade Policy (IATP). The group found minute traces of mercury in 17 out of 55 grocery items that contained high fructose corn syrup, but they didn’t run mercury tests on any grocery products free of the sweetener. The absence of a control group leaves the study’s conclusions open to many alternative explanations. For example, the trace levels mercury detected in IATP’s samples could be uniformly common in products found on grocery store shelves. A 2003 study conducted by scientists at Health Canada found measurable mercury levels in dozens of common foods, including baby formula, broccoli, carrots, celery, blueberries, grapes, peas, raisins, raspberries, rice, strawberries, and tomatoes.

Since elemental mercury is present nearly everywhere in nature, any quantity of mercury should be put into perspective of its danger to human health. But the IATP study relied on measurements so minuscule that they were expressed in “parts per trillion.” As it turns out, one liter of clean and safe drinking water contains more mercury than any of the grocery products IATP tested.


5. Myth: You can get mercury poisoning from the amount of fish you might consume in a given week or month.

The truth: Even if it were possible for Americans to eat enough fish to jeopardize their health from mercury intake, it would take decades for these speculative health effects to accumulate. In an official 2004 joint advisory, the EPA and Food and Drug Administration concede: "One week's consumption of fish does not change the level of methyl mercury in the body much at all."

There have only been four documented cases in history of people being poisoned by mercury in their food. In Iraq from 1971 to 1972, grain treated with a mercury-containing fungicide led to 6,000 hospitalizations and 500 deaths. The mercury levels measured in mothers from this region were as high as 674 parts-per-million. By comparison, the highest mercury concentrations among American women of childbearing age are only 1.4 parts-per-million. So this may sound scary, but some of these Iraqi women had mercury levels more than 400 times higher than what typical Americans experience from eating fish.

And during the 1950s, 111 people from Minamata City, Japan were poisoned after they ate fish contaminated by a nearby spill. These fish were artificially mercury-spiked with up to 40 parts per million (that's many times more than the highest levels found in U.S. fish). And then, as now, the Japanese ate far more fish than Americans ever have. In a similar case in 1965, 120 residents of Niigata, Japan were also poisoned by industrially-contaminated fish. According to University of Rochester School of Medicine toxicologist Dr. Thomas Clarkson, these Japanese poisonings are the only clinical cases anywhere in the scientific literature that document acute mercury poisoning from fish.


6. Myth: Every year in the United States, 630,000 children are born with mercury levels in their blood that put them "at risk" for neurological disorders later in life.

The truth: Kathryn Mahaffey, an Environmental Protection Agency scientist, created this outrageous statistic by estimating how many children would be born each year to U.S. women whose blood-mercury levels are above the EPA's "Reference Dose." But her calculation was not part of any official EPA statement, and the agency hasn't publicly supported it.

Besides, the Reference Dose Mahaffey relied on is ten times lower than the amount of mercury the EPA believes might cause a health risk. And while 7.8 percent of these women tested higher than the Reference Dose, absolutely none tested anywhere near the hypothetical risk level -- which is ten times higher.

To make matters worse, in 2004 Mahaffey claimed that since a developing fetus has more mercury in his/her blood than a pregnant mother, the estimate of "at risk" births should be doubled. She was right that there could be a difference between fetal and maternal mercury levels, but this difference had already been factored into the EPA's ten-fold "Uncertainty Factor" when its very conservative Reference Dose was calculated.

Of course, environmental scare groups like the Environmental Working Group and the Water Keeper Alliance have seized on the largest numbers available, proclaiming that 630,000 American babies are born every year at risk of severe mental impairment or neurological disease. But it's just not true. The CDC data that inspired this numerical trickery also shows that every tested American woman had mercury levels far below the threshold for any hypothetical health risk.


7. Myth: Eight percent of American women of childbearing age have unsafe levels of mercury in their blood.

The truth: This myth has its roots in the CDC's 1999 National Health And Nutrition Examination Survey (NHANES). It found that 7.8 percent of women of childbearing age had mercury levels in their blood that (in most cases, only slightly) exceeded the EPA's "Reference Dose." But this is the same Reference Dose that has a 10-fold cushion built-in, so the mercury levels in all but a few of these "8 percent" are between five and ten times lower than the level that represents a hypothetical hazard. They're not even close to incurring a health risk from mercury in the fish they eat.

But this hasn't stopped groups like Greenpeace and the Natural Resources Defense Council from trumpeting the "8 percent" number. They claim to be interested in helping pregnant women avoid unnecessary health risks, but it's hard to believe them when they throw good science out the window in the process, and encourage women to avoid the proven health benefits of fish consumption.

More recent government nutrition data has lowered this "8 percent" number to just 5.6 percent. But no matter. Even this 5.6 percent is adequately protected from mercury.


Guys this site was posted in another thread. There is some very interesting information there.
http://www.mercuryfacts.org

[Catcher's Mitt]

that's great news. now we can start using Merthiolate again. and that will get rid of the Staff problem.

No offense sportfishSTAFF.