incorrectly summarizes the central thesis of OSF as: "Too
much estrogen can reduce fertility (the Pill contains estrogen)
and interfere with fetal development."
This represents a profound, indeed ludicrous misunderstanding
of the issue. He simply doesn't understand what he is writing
about. The Pill typically (there are several types) works
by blocking the hormone surge that triggers ovulation. This
has nothing to do with the mechanisms studied by the National
Academy of Sciences or covered in OSF, which are about
how an embryo grows to adulthood. Hormone disrupting chemicals
alter the course of development of the exposed individual.
When they have effects on fertility, it is through some impact
on the reproductive tract of the exposed fetus once it reaches
only is his depiction of the role of estrogen wrong, one of
the central points of OSF is that the mechanisms of
action of hormone disrupters are quite varied. As documented
elsewhere on this website, while some of the best studied
act like estrogen, others act like anti-estrogens and anti-androgens.
Still others interfere with thyroid hormone, with progesterone
and with the retinoid system.
writes: "Colborn spends several pages on deformities in
frogs, for example. Recent papers published in the technical
journal Science attribute frog deformities to a natural parasite,
not a hormone plague."
We spend less than a paragraph on frog deformities in OSF,
in an epilogue published a year after the hardback came out.
That discussion explicitly acknowledges the parasite hypothesis
as one of three hypotheses under exploration. The original
version contained a little over 2 pages on frog disappearances,
a substantively very different issue, and in that discussion
we present it as an issue warranting research, not a problem
that has been solved. We report accurately in the book that
one of the leading herpetologists in the world raised the
question of whether endocrine disruption was driving frog
disappearances. Moreover, were Easterbrook familiar with the
science on frog deformities, he would know that while
the parasite hypothesis may explain deformities in certain
areas of the western United States, experts still identify
pesticides as the most plausible (but still unproven) explanation
for much of the East and mid-West, the regions of the country
where this problem is most pronounced and where the parasite
hypothesis does not offer a sufficient explanation. He might
also be aware that the lead author of the Science paper to
which Easterbrook refers has commented publicly that even
if parasites may offer a mechanistic explanation for how deformities
take place in the pond he studied, he believes pesticides
or some other chemicals may be involved in producing the overabundance
of parasites which has led to unnaturally high rates of frog
deformities. An excellent book by William Souder, A Plague
of Frogs, offers a cogent summary of where the research
on frog deformities is headed.
writes: that the National
Academy report found the theory of endocrine disrupters
possibly true but "unsupported by experiments or health data."
That is a clever but profound distortion of the Academy's
conclusions. The theory is amply supported by hundreds of
published experiments on laboratory animals showing endocrine
disruption operating in mammals at low contamination levels
comparable to exposures experienced by people and animals
in the real world.
National Academy report700 pages+ longreviews
many of these published results. It concludes that exposure
to endocrine disrupting chemicals during critical periods
of development "can interfere with normal reproductive development."
What is lacking, which we readily and repeatedly acknowledged
in OSF, is scientific certainty that endocrine disrupters
at levels experienced by the public at large Here the academy
concludes that "humans are almost universally exposed." Human
exposures are commonly within the range of contamination levels
shown in laboratory work to cause animal health effects.
Academy report also states that "PCBs have been shown to influence
neurological development in animals and that there are consistent
correlations in people between prenatal exposure to PCBs and
cognitive deficits. No one, fortunately, has been willing
to do the rigorously-designed experiments on human embryos
and developing children that would be required to satisfy
the highest level of scientific proof, because these tests
would be immoral. Ironically, the fact that human exposure
is almost universal means that non-rigorous experiments are
underway already. Easterbrook (and industry) point to the
lack of scientific certainty emerging from these weak experiments
as proof of chemical safety, when instead it is an acknowledgement
of scientific ignorance. This ignorance is why the Academy
and OSF place such a high premium on research questions.
OSF goes further, however, and recommends precautionary
measures be applied to limit the ongoing unintended chemical
experiments resulting from widespread, uncontrolled exposures.
writes: OSF based its case for the human endocrine-disruption
effect almost entirely on the example of diethylstilbestrol
The DES story is central to OSF, but it is by no means the
only example of endocrine disrupters affecting human health.
As the National Academy report discusses, endocrine disrupting
chemicals have affected human health in several well-studied
accident-related industrial exposures at relatively high levels.
Neurological effects are associated with exposure to at least
one endocrine disrupting family of chemicals, the PCBs. The
mechanism of toxicity is uncertain but the impact is well-established
by several independent studies. Thus endocrine disrupting
chemicals do affect the well-being of many Americans at levels
to which they are currently exposed.
crucial question, left unresolved by current research, is
whether endocrine disrupting chemicals as experienced by many
Americans cause health problems like cancers or sperm count
declines. The National Academy report does not conclude
this hasn't happened. It concludes the relevant research has
not been done. It also concludes that animals exposed
experimentally to those same levels experience health effects.
And that animal studies are useful guides to predicting human
NAS report was limited in the strength of its conclusions,
moreover, by the fact that it was unable to systematically
incorporate the plethora of studies that have come out since
June 1997, which is when they stopped considering, for the
most part, new studies.
writes: that the EPA initiative to test for endocrine
disrupter effects (EDSTAC) is at odds with the Academy's conclusion.
The NRC's concludes that its recommendations are consistent
with EDSTAC's. It calls for extensive testing precisely along
the lines of what EDSTAC is planning.
writes: "when the Antarctic ozone hole was detected, the
science world immediately embraced the finding."
Many prominent scientists expressed skepticism at the time.
The history of the prediction and confirmation of ozone depletion
is rife with scientific disagreement. His misrepresentation
here is a convenient set-up to compare "political" vs. "scientific"
support for ozone depletion vs. endocrine disruption.
comments: "every ecological problem, save global warming,
shows a positive trend."
This is dumbfoundingly wrong. The most conspicuous
example here is the loss of biodiversity, which is accelerating.
But even among those issues that he describes as improving,
the picture is not nearly as pollyannish as he asserts. For
example, even if nitrous oxide emissions from some sources
are decreasing, the biological impacts of acid rain are showing
no signs of reversing and indeed their consequences are emerging
as far more devastating to eastern forests and watersheds
than had been concluded 10 years ago.
the stratospheric ozone situation is hardly positive... global
warming is causing a cooling of the stratosphere, more polar
stratospheric clouds and increased danger of stratospheric
ozone losses in the Arctic.
asserts: that Our Stolen Future was the "one of
the best promoted book in publishing history?"
We appreciate the compliment, but let's be realistic. Best
promoted compared to what? To a John Grisham or Tom Clancey
novel? To The Bell Curve" or It takes a village
or even Monica Lewinsky's biography? Easterbrook's exaggeration
here is important because it is one that most general readers
will realize doesn't pass the smell test. His distortions
on the scientific issues he raises are no less egregious,
but are perhaps less transparent to most New Republic readers.
writes (of a controversial study
by John McLachlan's lab on synergistic interactions among
contaminants): "McLachlan studied the effects of chemicals
not on mice or cell cultures but on yeast colonies. Yeast,
a fungus, operates according to principles entirely different
from those of mammalian cytology; it is a pitiful proxy for
Academic scientists and industry scientists alike use yeasts
to study the behavior of human hormones and endocrine disrupters.
These yeasts have been altered using bioengineering techniques
to contain human hormone receptors. For this specific use,
there is no mainstream scientific argument about their relevance
to humans. Easterbrook's comment here simply reveal his ignorance
of these research issues.