Another Phony Health Scare

By Gregg Easterbrook
Copyright 1999 Sacramento Bee
September 12, 1999

Buried in the back pages of the newspapers a week ago were reports that the National Research Council (NRC), an arm of the National Academy of Sciences, had found no proof that synthetic chemicals act as human "endocrine disrupters." The NRC declared the theory of endocrine disrupters "rife with uncertainties" -- possibly true but unsupported by experiments or health data. This may sound like a humdrum scientific data blip. But it's major news. For three years now, organizations ranging from environmental groups to Consumer Reports have been proclaiming the existence of a deadly wave of endocrine disrupters that cause cancer, infertility and personality abnormalities. It's been said that endocrine disrupters are so malignant that they even render plastic plates and baby bottles potential killers.

The notion of menacing endocrine-disrupter chemicals has gained substantial backing from the talk show press, Congress and the White House. Vice President Al Gore has taken up the cause, declaring that there exists a "large and growing body of scientific evidence" that endocrine disrupters threaten humanity. Recently, the Environmental Protection Agency (EPA) began a major initiative to test some 15,000 synthetic substances for endocrine-disrupter effects, an effort slated to continue despite the NRC's inability to verify the underlying phenomenon.

It is possible that a human endocrine-disrupter effect exists and yet eludes the National Academy of Sciences; some health problems of the past have been slow to reveal themselves to researchers. It is also possible that the endocrine disrupter is a case study in the art of the politically potent false alarm. Cancer from power line electromagnetism and asbestos in school walls, two ideas that, though now discredited, once commanded national political attention despite sketchy research, come to mind. Is there really danger here, or just another stylish panic?

The idea of a plague of endocrine-disrupter chemicals jumped from something discussed only in research circles to a topic entertained at the White House level after the 1996 publication of "Our Stolen Future," one of the best-promoted books in publishing history. The work listed three authors: Theo Colborn, a zoologist at the World Wildlife Fund (WWF); Dianne Dumanoski, a writer; and John Myers, a former zoologist who now heads the W. Alton Jones Foundation. The Jones Foundation, which is to the left roughly what the Rutherford Institute is to the right (through some weird convergence, they're both located in Charlottesville,Va.), invested in promoting "Our Stolen Future" and also in funding studies to provide further evidence in support of its thesis. Publication was accompanied by newspaper advertising, TV appearances for the authors and considerable newsmagazine coverage. Gore wrote a lavishly complimentary foreword to the book, calling it the "sequel" to "Silent Spring," and, during the book launch, gave a speech endorsing the volume and its theory. Within the book, and in the marketing and press coverage, Colborn and Myers were repeatedly depicted as detached, objective scientists, though neither lists an academic affiliation and both are full-time employees of advocacy organizations.

The thesis of "Our Stolen Future," a well-written and thoughtful book, is that many synthetic compounds, from banned chemicals such as DDT and dieldrin to such apparently benign substances as plastics used to make baby bottles, mimic hormones when they enter the body; they usually act like estrogen. Too much estrogen can reduce fertility (the Pill contains estrogen) and interfere with fetal development.

Colborn came to her thesis from studies of birds of the Great Lakes region, where several avian species are imperiled. She initially hypothesized that residual toxins such as DDT and PCBs (both banned in the United States for two decades but still present in trace quantities in the biosphere) and dioxin (not exactly banned but very tightly regulated) were causing a wildlife cancer epidemic. Her research did not find unusual wildlife cancers but did turn up many birds with reproductive problems. At about the same time, other researchers were finding sexual abnormalities and congenital defects among frogs, alligators, Florida panthers and other creatures. Colborn hypothesizedthat DDT, PCBs and other compounds were affecting the endocrine systems of wildlife. The NRC report validated her theory on that point; it concluded that some synthetic compounds do harm wildlife in ways that may be related to hormones, while saying it could find no similar effect in people.

Three months after "Our Stolen Future" arrived in bookstores, a Tulane University researcher named John McLachlan published a study that appeared to lend terrifying immediacy to the book. One reason many health researchers don't worry excessively about traces of toxic chemicals is that, in very small amounts, they seem to have little or no effect. But we aren't exposed to individual chemicals in isolation; traces of many synthetic compounds are in our bodies. Tulane researchers announced that they had studied the effects of small amounts of four synthetic chemicals at the same time and discovered a previously unknown amplification effect -- individual traces did little, but together they made one another 1,000 times more potent as endocrine disrupters. McLachlan was already one of the scientists on whose research "Our Stolen Future" is prominently based; the text cites him eight times. Now he had apparently found a dramatic confirmation of the book's thesis.

EPA officials and members of Congress were aghast at the Tulane study. A month after its release, Congress unanimously passed the Food Quality Protection Act, which, among other things, directed the EPA to begin studying endocrine disrupters. A total of five months elapsed from the publication of "Our Stolen Future" to the enactment of major legislation based on the book's thesis. Rarely has any work influenced public debate faster.

Red flags about the Tulane study were missed. For one, Tulane's endocrine program is funded partly by the Jones Foundation, the organization behind "Our Stolen Future" coauthor Myers. For another, 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 a person.

When other researchers attempted to replicate McLachlan's findings, they couldn't even get the yeast to show the dubious effects he had claimed.In July 1997, about a year after Congress passed the endocrine-disrupterlegislation, McLachlan quietly withdrew his paper, saying "there must have been a fundamental flaw" in the experiment. The panic button had been pushed over a scientific finding that, in the end, was invalidated, just as much of the power line scare was based on research later found to contain fabricated data. Many newspapers, newsmagazines and television newscasts that had prominently reported the scary Tulane endocrine-disrupter claims said nothing about McLachlan's retraction. The federal law stayed in effect, and various lobbies continued to promote endocrine-disrupter-related bills with ardor. In the fall of 1997, months after the Tulane study crashed and burned, Colborn would declare that "overwhelming evidence" supported her idea.

"Our Stolen Future" laid out the evidence that wildlife continues to suffer from traces of DDT and PCBs, causing its authors to advocate a global ban against these substances. That recommendation is dicey because DDT is the most cost-effective counter to the malaria mosquito, a much more pressing health threat in developing nations than endocrine disruption. The book argued persuasively that, because hormones are potent in tiny amounts, modest levels of hormone-mimicking chemicals might pose a danger even as the overall level of pollution declines. "Our Stolen Future" is further impressive in that it counseled activists to let go of their obsession with a "cancer epidemic," a notion that is strong in pop culture but not in medical research. (Short version: Cancer incidence increased from about 1970 to 1990, but mainly because of cigarette smoking and the aging of the population; in the 1990s, overall cancer incidence has declined, though the rate of occurrence of a few types of the disease continues to rise.) "We must move beyond the cancer paradigm," "Our Stolen Future" declares. This aspect of the endocrine-disrupter theory runs refreshingly against the grain.

So far so good. But "Our Stolen Future" went on to engage in broad speculation about an entirely new category of health menace that is, mysteriously, both deadly and undetectable; we're sick, and we don't even know it.

First, the book lumped together nearly every form of observed wild life malady as indications of endocrine disruption, regardless of competing explanations. 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.

Next, "Our Stolen Future" based its case for the human endocrine-disruption effect almost entirely on the example of diethylstilbestrol (DES), the drug that, when taken by pregnant women, caused thousands of girls to be born with abnormal reproductive tracts or to develop cancer. DES was a horror, but the harm was caused by large doses of chemicals that mothers ingested directly, not trace quantities in the environment.

As the manifesto of a new health concern, "Our Stolen Future" is deeply puzzling in that it declares the advent of a widespread, pervasive harm without addressing why, if that were so, U.S. public health has been improving steadily. Americans as a group have achieved longer life expectancy, less heart disease, fewer strokes and lower mortality from almost all diseases, all during the same period that society was inundated with the chemicals on which the endocrine-disrupter theory is based. Perhaps, absent disrupter chemicals, public health improvements would have been better still.

"Our Stolen Future" declared that the most ominous sign of the endocrine-disrupter plague was a global decline in sperm counts, suggesting that hormone-mimic chemicals might lead to the extinction of human life -- hence the "stolen future." The book's claim about sperm count decline was received as a sensation, the science fiction cliche of a sterile human race suddenly looming real. Many media outlets treated the vanishing-sperm theory credulously (notable exceptions being the New York Times and the Seattle Times, which cast doubts from the start). The WWF, the World Resources Institute, Greenpeace and other organizations began featuring endocrine-disrupter themes, with Greenpeace fund-raising ads declaring, "YOU'RE HALF THE MAN YOUR FATHER WAS, owing to falling sperm counts."

On one level, the idea that environmentalism now warns in dire tones of decreasing sperm counts is delightfully goofy, since it also warns in dire tones of increasing human numbers. Population rising? Oh my God! Fertility declining? Oh my God! Given that developing nations are said by many greens to be committing social and environmental suicide via population growth, if otherwise benign synthetic compounds really reduce human fertility, then shouldn't we shower the world with plastic plates?

But the state of the sperm is much less certain than the endocrine-disrupter theory lets on. In Western countries, fertility therapy is an expanding area of health care, with male fecundity problems increasingly seen as being just as consequential as those of females. But the boom in male reproductive medicine stems from the fact that couples are postponing child-bearing until the time of life when sperm production naturally declines; you don't meet many 19-year-old guys in fertility clinics. On the question of sperm itself, several respected studies, including one from Scotland, have found both falling counts and lower sperm motility, mainly in northern European men born after about 1970. Several equally respected studies have found either no change or that sperm-count reductions are regional, the conclusion of an important recent study at Columbia-Presbyterian Medical Center. "There is simply no consensus in this area," says Larry Lipshultz, a urologist at Baylor College of Medicine and an authority on fertility-related issues.

Advocates of the endocrine-disrupter theory make much of a study by Danish researcher Niels Skakkebaek, who concluded in 1992 that, globally, sperm counts declined 45 percent during the postwar era. Skakkebaek's study has been the subject of intense criticism within his field because for the early, baseline years he employed United States sperm count figures, which are unusually high (you'll be proud to know that America leads the world in sperm), and for the later, alarming years, he mostly used sperm statistics from the developing world, where men usually test with lower levels. Studies that compare apples to apples, examining men in the same place, don't usually find the scary swing Skakkebaek reported, with a few exceptions such as the Scotland study.

Just why there are regional differences in sperm counts is unknown. Recent reports published in the technical journal Fertility and Sterility showed, for example, that New York men consistently exhibit higher sperm counts than men in Los Angeles. Why? "No one has the slightest clue," says Lipshultz. It seems that gawking at California beach babes does not have the expected effect on the hormone production of L.A. males. On the other hand, waiter, I'll take another glass of that Manhattan tap water, please.

If sperm counts are lower in northern Europe or in the developing world, it may be that some impending environmental threat lies undetected. Absurdly, in the case of Europe, the explanation may be more prosaic: underwear. For inexplicable reasons of fashion, since the '70s European males have favored extremely tight, pantylike briefs that are much more snug than briefs sold in the United States. The testicles are outside the body for evolutionary reasons, because sperm formation requires a cooler temperature than 98.6 degrees Fahrenheit. Very snug briefs that press the family jewels against the warmth of the leg may interfere with sperm manufacture. (Believe it or not, there's been academic research on the boxers vs. briefs controversy, and the most recent study -- conducted at the State University of New York at Stony Brook -- discounts snug underwear as the culprit.)

Or it may be that modern men are eating their way to lower fertility. One of the plants richest in natural estrogen-mimic compounds is the soybean. Until this century, soy was rarely a major component of the human diet. During the postwar era, high-yield Green Revolution strains have spread the cultivation of this nutritious bean, the typical American now annually consuming (in oil and other products) about 65 pounds of it. Meanwhile, soy has become a staple of the developing world. Some researchers think the form of estrogen-like compound in soy doesn't remain in the body long enough to have a significant effect; others aren't sure. Either way, something to ponder when ordering that healthful soyburger.

Though it is possible that the endocrine-disrupter theory will eventually be proved right about sperm counts, it is not a good sign that many advocates brook no disagreement on this point. "Our Stolen Future" treats skeptics of the vanishing sperm as antediluvian, declaring that criticism of the Skakkebaek study "recalls similar disbelief at the first news in 1985 that a dramatic ozone hole had developed." But, when the Antarctic ozone hole was detected, the science world immediately embraced the finding; it was the political world that disbelieved. In the case of claims about endocrine disrupters, it is the political world that is jumping aboard, while the world of science is not persuaded.

That there are fundamental reservations about the endocrine-disrupter theory is something most environmental lobbies play down. The WWF has a Website devoted to the theory, and it's just a click away from donation information. The site presents synthetic endocrine disruption as an established medical condition; it lists "scientific consensus documents" supporting the theory, but dates on the documents stop at 1996, when the retractions and counterfindings started coming in. The WWF, Greenpeace and similar organizations gloss their contentions about endocrine disrupters with the shiny adjective "scientific." "Our Stolen Future" rolls out the word "science" on page after page, yet the book contains sentences such as one that claims endocrine disrupters "jeopardize the survival of entire species -- perhaps, in the long run, even humans." Setting aside the unscientific hyperbole of extinction warnings based on an effect whose existence has not yet even been confirmed, humans are not a"species." The word "human" means "member of the genus Homo," the term encompassing extinct ancestors such as Homo habilis. People of today bear the species name Homo sapiens. A small point, but one relevant to the work of thinkers who describe themselves as scientific zoologists.

For her part, Colborn makes increasingly loose claims about endocrine disrupters. She suggests that hormone-like chemicals may cause "widespread erosion of the human potential," "aberrant and unhealthy tendencies" and may contribute to "the breakdown of the family and frequent reports of child abuse." Her reasoning? That divorce and child abuse are happening at the same time as the use of synthetic compounds expands, a formulation violating the Logic 101 rule that correlation establishes nothing about causation. Colborn suggests endocrine disrupters may be making test scores fall, but many test scores are now rising. She suggests endocrine disrupters may contribute to increased violence, but violent crime has been in decline for almost a decade. "My heart aches for parents and those who have chosen careers to work with children" because the next generation is doomed, she said in a recent speech. After the NRC findings were released, Colborn told Gina Kolata of the New York Times: "Just because we don't have the evidence doesn't mean there are no effects."

In the United States, almost every ecological problem, save global warming, shows a positive trend. Acid rain, water pollution and smog emissions are decreasing even as the economy grows. Ozone-depleting CFCs have been banned, and the stratosphere is expected to recover. The "poisoning of America" has failed to happen, with toxic discharge by U.S. industry having fallen to less than half the level of a decade ago, while almost everyone is leading longer, healthier lives.

Perhaps there are dangerous endocrine disrupters. Obviously, we must find out. If the EPA effort finds even one confirmed synthetic hormone-mimic that harms people's health, then the scare has all been worthwhile. But, in cases such as this, or the power line cancer or asbestos in schools scares, it's strange to think how quickly speculative, lightly researched claims, advanced by advocates with a fund-raising interest, can go straight to the top of the national policy agenda, while so many undeniably genuine problems languish.