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Feature Story
Bad Chemistry: A Special Report
Page 5

WE ARE UNPROTECTED   Fewer than a thousand of the 100,000 synthetic chemicals have been tested for endocrine disruption by anybody, but even the little we know is alarming. Sadly, the government's effort to mount a response has been checked continually by insufficient funding for research and regulation, by the complexity of the science that must be done, and by industry's well-funded efforts to delay the EPA's plans to test chemicals.

After the Wingspread conference, Colborn worked to raise awareness of endocrine disruption in citizens and legislators. With two gifted collaborators, John Peterson Myers and the science writer Dianne Dumanoski, Colborn wrote Our Stolen Future, a book for the lay reader. In 1996, the year it was published, Congress passed ambitious legislation mandating the testing of all synthetic chemicals to determine whether they cause endocrine disruption. The Endocrine Disruptor Screening and Testing Advisory Committee (EDSTAC) was charged to recommend a testing protocol within two years.

From the start, EDSTAC faced considerable obstacles. One was its size: 39 members, including chemical company representatives and environmental activists, but only five bench scientists. Gina Solomon, a Harvard-trained physician who had just started work at the Natural Resources Defense Council (NRDC), where she is now a senior scientist, remembers, "It was often hard to get a word in edgewise, let alone talk through anything." She adds, "These were public meetings with audiences of up to 100, held in anonymous airport hotels around the country so there could be local participation and comment, which is a good thing, but it created a disconnect. The committee was charged to do a very technical scientific task."

Discussions were contentious. Representatives of some chemical manufacturers were accompanied by teams of lawyers who had to consult on every issue. At one point, the committee reached a seemingly hopeless impasse on how to define an endocrine disruptor. A compromise was finally achieved when Colborn suggested that they "describe" rather than "define" the term. How to define an adverse effect of an endocrine disruptor also ate up oceans of time. The law required an investigation of estrogenic effects of synthetic chemicals but did not limit the investigation to estrogen alone. Industry wanted to look only at estrogens, while Colborn and others believed all hormones should be studied. Eventually androgens were included, and later thyroid hormones were added as well, but it took months to reach these agreements. (Other hormonal systems that are not yet part of the testing include the pancreas, where malfunction can lead to diabetes or obesity; the pituitary gland; the pineal gland, which controls sleep; and the thymus, critical to the immune system.)

The committee was also divided about whether the goal was to protect human health or the health of wildlife. Colborn considered this a false dichotomy because she does not see animals and humans as two groups with separate fates. If wildlife suffers, so do humans. Yet, while evidence of harm to wildlife was mounting, how to pin down causal connections to human health remained a vexed question. Representatives of industry were quick to exploit the dilemma inherent in the research: They argued that anything less than the gold standard of experiments conducted with human control groups would be "unsound science," experiments that everyone agreed could never be conducted for ethical reasons.

Despite these difficulties, EDSTAC met its deadline: In August 1998, its final report recommended 14 assays, or tests, and a plan for making decisions about how many of these tests a chemical had to pass before it could be deemed safe.

Not even one assay has been approved As we go to press. Before testing can begin, protocols have to be agreed upon for conducting each assay and then each assay has to be validated by running trials in multiple labs to prove that results are reproducible from one lab to the next. Establishing protocols and validating them has proved to be extraordinarily difficult and time-consuming.

But the work is all the more important because the chemical companies themselves will be responsible for conducting these tests. Still, the process of validating the government's battery of assays has eaten up seven years. Colborn says that lack of resources has been the biggest deterrent to progress: "With the lack of funding and the limited staff provided to the EPA, we could not have expected much more." Solomon of the NRDC is cautiously optimistic but warns that validation has seemed within reach several times before, only to be disrupted by unforeseen difficulties. Colborn fears that money and time will be thrown away testing high doses instead of low doses, on adult rats rather than embryos, on Charles River Sprague Dawley rats that won't react.

Gray is, like Colborn, keenly impatient with the delays, but he believes the proposed assays will tell us what we need to know. "We have reliable screening assays for identifying estrogens and anti-estrogens and androgens and anti-androgens that have been used in the scientific community for decades," Gray says. "These assays are reproducible, and they're diagnostic of endocrine effect. They produce valid, interpretable results."

Forecast: Dry and Brutal
Mammoth Mystery

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OnEarth. Winter 2006
Copyright 2005 by the Natural Resources Defense Council