By Willie Soon and Robert Ferguson

Perhaps the most repeated refrain driving the mercury alarmism campaign
is that "630,000 American babies are born each year" with elevated
concentrations of mercury in their blood, with the potential for
"permanent brain damage and learning disabilities." These infants are
said to be "poisoned" at birth because their mothers consumed fish
containing microtraces of mercury. As a result, pregnant women are being
terrified away from fish consumption, and thus denied a source of
nutrition shown to enhance both fetal brain development and maternal health.

The genesis of this myth was the 2003 Centers for Disease Control
release of its results from the 1999-2000 nutrition and health survey.
It was reported that 8% of women of childbearing age (16-49 years old)
had blood mercury concentrations above the so-called "safe" mercury
reference dose established by the Environmental Protection Agency (EPA).
Since there are over four million births in the U.S. annually, mercury
opponents and several government scientists extrapolated that at least
320,000 babies born are "at risk" in the U.S. each year due to "unsafe"
mercury levels in their mother's blood.

In January 2004, an EPA employee revised the number of babies born at
risk upward to 630,000, based on "new" information that mercury in
maternal cord blood (shared with the fetus) is more concentrated than in
body blood. But the information was not "new," it was a double-counting,
since the EPA had already accounted for the blood-concentration
difference in 2001, helping make its "safe" mercury dose the most
stringent in the world.

It must be recognized that the EPA's safe mercury dose is based on
inappropriate studies of people who consume whale meat and blubber (a
unique diet very different from typical U.S. consumption) containing
multiple chemicals -- PCBs, cadmium, pesticides, persistent organic
pollutants, DDT, etc. -- of which mercury is only one.

There are other reasons why mercury alarmists' emotive claims are
neither justified nor credible. For example, a recent survey in Japan
reported that 87% of the population, including 74% of Japanese women of
child-bearing age, had mercury concentrations above EPA's "safe" level.
Logically, one must either conclude that generations of Japanese are
"brain-damaged" (and suffering from severe and permanent learning
deficits), or that EPA's "safe" mercury dose is simply arbitrary and
extreme.

Similarly, children in grades four and eight from traditionally
high-fish-consumption cultures in Japan, Korea, Singapore and Hong Kong
consistently outperformed U.S. students on international standardized
math and science tests. This despite the fact that Hong Kong children
have mean blood mercury levels some 10 times higher than U.S. children.
Even the mummified remains of four Aleutian infants dated to 1445 A.D.
contained higher mean mercury levels than young children reported in the
CDC surveys.

None of these findings are surprising, considering numerous studies
report no adverse affects on children from maternal fish consumption --
as high as 12-14 meals per week -- of the kinds of fish widely available
in U.S. markets and restaurants. Only benefits have been reported, such
as superior eyesight, higher child mental development scores, less
hyperactivity, good heart and brain function, and improved intelligence
at four years of age.

Finally, an examination of the actual CDC data shows that the 1999-2000
survey documented seven out of 705 children (or 1%) with blood mercury
above the EPA's "safe" mercury dose, while the 2001-2002 survey found
only four out of 872 children (or 0.5%) exceeding it. More importantly,
even the highest mercury level measured in this four-year survey has a
safety cushion of more than 500% of the lowest exposure level of concern.

Yet hardly anyone is rushing to report these important updates, let
alone downward revisions in the numbers of children "at risk." Instead,
one observes repetition of the near-religious dogma that "600,000-plus
American children are born each year" at risk of "birth defects,
including mental retardation and problems with motor skills."

Basing enormously consequential energy and health policies -- both
nationally and internationally -- on myth is both irresponsible and harmful.

Mr. Soon is chief science researcher, and Mr. Ferguson executive
director, of the Center for Science and Public Policy.


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Originally published in the Wall Street Journal.