Updated

Anti-chemical activists achieved a major victory this week. A government-sponsored panel of scientists laid the foundation for banning virtually any chemical on a whim.

A National Toxicology Program panel concluded that there is "credible evidence" that some chemicals can affect laboratory animals at very low levels — well below the "no effect" levels determined by traditional testing.

This shocking, self-contradictory conclusion violates a fundamental principle of toxicology — namely that "the dose makes the poison." That is, all substances — including water, salt, and sugar — are poisons in sufficiently high amounts or doses. Below their "toxic" doses, substances aren't poisons.

The chemicals most at risk are components of plastics used in food packaging, pesticides and other industrial compounds that have been under activist attack as so-called "environmental estrogens" or "endocrine disruptors" — hormone-like chemicals in the environment that are alleged to disrupt normal hormonal processes and cause everything from cancer to reproductive problems to attention-deficit disorder.

The endocrine-disruptor scare flared up about five years ago with the publication of the book Our Stolen Future, an alarmist compendium of anecdotal tales of chemicals allegedly wreaking havoc on the hormonal processes of humans and wildlife.

The twist with the endocrine disruptor scare was the novel but unsubstantiated notion that even very low exposures to certain chemicals, below what were previously viewed as safe levels, could be harmful.

After five years and $5 million of taxpayer-funded research, the case for the Our Stolen Future theory has only weakened.

Though the Our Stolen Future activists have little more than assertions, they advance their cause with financial support from left-wing foundations and their political connections.

Their claims are based in the work of Our Stolen Future cult leader and University of Missouri researcher Frederick vom Saal. His experiments on laboratory mice supposedly show that very low doses of some chemicals — thousands of times lower than current safe standards — increased prostate weight in male mice and advanced puberty in female mice.

No other laboratory has been able to reproduce vom Saal's work. Traditionally, reproducibility of experiments is necessary before results may be considered "scientific."

But vom Saal all but guaranteed that his work will never be reproduced. His experiments involved a unique strain of mice that he inbred in his laboratory for about 20 years. When the mice stopped producing the results he wanted, he killed them.

Without the same strain of mouse, vom Saal's experiments can't be reproduced by others and his work can't be thoroughly evaluated.

But vom Saal didn't have to kill his mice to prevent criticism of his work. Allies on the NTP panel would give him a free pass.

The panel met last October at the request of the Environmental Protection Agency. The EPA asked the panel to determine whether low doses of chemicals can interfere with hormonal processes. The EPA is required by a 1996 law to develop a screening program for chemicals suspected of having hormonal effects.

The panel asked the public to nominate studies to be reviewed. Ground rules required that a study's raw data had to be submitted to the panel as a prerequisite for the study to be considered. The panel wanted to subject the data from these studies to "independent analysis."

Vom Saal's studies were nominated, but he didn't submit his data. Inexplicably, the panel changed the ground rules to allow consideration of vom Saal's studies anyway. The reason it did that had more to do with intimidation of panel members than science, according to those involved in the process.

The panel was stocked with powerful allies of vom Saal, including former EPA pesticide chief Lynn Goldman and NTP toxics chief George Lucier. Though there was plenty of reason to dismiss vom Saal's work and the low-dose theory, panel members not allied with vom Saal lacked the courage to do so.

The implications of the panel's report are unsettling. The panel recommended that the EPA consider changing its guidelines for assessing risk of reproductive and developmental effects from chemicals. The recommendation is likely to spread to other national and international regulatory agencies.

The low-dose theory coupled with vom Saal-style "science" puts virtually every industrial chemical and many consumer products at risk of being stringently regulated or banned without a scientific basis.

It's the anti-chemical activists' dream come true.

— Steven Milloy is the publisher of JunkScience.com, an adjunct scholar at the Cato Institute and the author of the upcoming book Junk Science Judo: Self-Defense Against Health Scares and Scams (Cato Institute, 2001). Mr. Milloy may be reached at milloy@cais.com.