One of my pet peeves is the funding of questionable “scientific” studies by federal agencies like the EPA. Another is the presentation of “junk science” in our court rooms by very well-compensated “expert” academics. A third is modern science’s obsession with gender issues, to the point of absurdity. So naturally this headline by Curtis Porter at the American Council on Science & Health (ACSH) caught my eye:
Dr. Swan to Infant Boys: Stop Being So Girly
First, an excerpt from Porter’s piece:
So, WebMD relays the results of a new study by Dr. Shanna Swan of the University of Rochester Medical Center published in the International Journal of Andrology: “Mothers exposed to high levels of chemicals known as phthalates during pregnancy may have boys who are less likely to play with trucks and other male-typical toys or to play fight.”
If this sounds absurdly unscientific to you, it’s because it is. “Dr. Swan clearly started with her desired result and worked backwards to find some pseudo-scientific factors to justify it,” says ACSH’s Dr. Gilbert Ross.
“Shanna Swan has made a career out of studying phthalates and trying to find reproductive effects from them,” says ACSH’s Dr. Elizabeth Whelan, who has crossed swords with Dr. Swan on the subject before.
“A few years ago she conducted a study that alleged there was a ‘feminizing’ effect on baby boys from phthalate exposure based on a metric she made up called ‘anogenital distance,’” explains Dr. Ross. “That study has since become part of the lore of anti-science groups who dislike phthalates. This latest study is equally horrendous. I could go through the article and say all the ways it is completely nonsensical, and we’d be here all morning, but I will mention that she reverts to her preferred strategy of using parameters that she admits she made up on the spot when she’s watching these baby boys playing with toys.”
“This is junk science at its worst,” adds Dr. Whelan. “And I’d just like to point out that Shanna Swan recently got a $5 million dollar grant from the EPA to continue with this terrible research.”
Question 1: It costs $5 million to screen boys and watch them play with trucks?
Question 2: What is “anogenital distance” and why is it alleged to be a “feminizing” factor?
Question 3: Who is Dr. Shanna Swan? ACSH, a well-respected organization, seems to disagree with a lot of her work.
A Google search on “Swan” and “expert” and “testimony” returned this article from Forbes. It answers two of my three questions. (“Anogenital distance” is the distance between the anus and the genitals. More on this in a bit.)
From the Forbes piece:
Once upon a time–this week, actually–mothers all over the world woke up and wondered whether their little boys were increasingly behaving like little girls. The cause for this sudden concern: a new study claiming chemicals in everyday plastics might be feminizing their brains.
Was this a feminist plot to end patriarchy and violence? A cunning plan by doll manufacturers in a hitherto-hidden war with toy-truck makers? A long-term strategy to improve the growth potential of grooming products for men? No, it was just another study that the media rushed into publication without any pause to examine how it was assembled.
However, what the reports failed to mention was the weak statistical data the authors of the study employed to reach this conclusion.
As the author of Forbes piece goes on to say, we live in a “virtual junkyard of information, a growing, steaming pile of statistical garbage and toxic nonsense that won’t decay and disappear.” False findings in modern “scientific” research are common, and researching the accuracy of research is now a field of scientific study. On top of that, the media’s eagerness to quote Swan and other so-called “experts” births, as the Forbes piece also points out, that mythical beast known as “a growing number of scientists.”
The author of the Forbes piece goes on to cite a number of court cases, including one that made it to the Supreme Court, in which Dr. Swan’s studies and testimony were so poorly regarded that they were ruled inadmissible.
So, now, the “anogenital” thing (again quoting from the Forbes piece):
Take the chemicals in vinyl and cosmetics that are supposedly feminizing baby boys. Though phthalates have been a target of environmental activist groups for years, they only rose to recent prominence thanks to one highly-publicized 2005 study by Shanna Swan.
Swan claimed that levels of certain phthalate metabolites in pregnant women correlated with a lower anogenital index (AGI) in their male children. AGI is a measurement of the distance from the anus to the base of the penis, divided by the weight at the time of measurement.
There wasn’t a consensus as to what a normal range for AGI was in baby boys or whether it is significant, but there was evidence that a shorter AGI correlated with a slower rate of testicular descent in animals. When a National Institutes of Health (NIH) expert panel later evaluated her study, it didn’t find her evidence wholly convincing. All the babies in the study had normal genitalia with no sign of defects.
But Swan wrote an op-ed in the San Francisco Chronicle claiming that “In-utero exposures to phthalates can lead to birth defects and genital malformations … in baby boys.” Such a claim disregarded her own study and would never have passed peer review. Environmental activists and journalists then seized on her public comments as proof the public was at risk. Phthalates and Shanna Swan suddenly became the poster boy and girl for deformed penises.
Dr. Swan later mined through new data she compiled. On the basis of finding two correlations that reached statistical significance, she announced to the world that some phthalates could change male behavior and feminize little boys.
Two?
Two correlations are a long way away from evidence of causation, friends. On that basis, Swan feels justified striking fear in the hearts of mothers regarding the health and/or masculinity of their boys? And Dr. Swan is supposed to be a well-respected expert in her field? It seems, as the Forbes piece said, that:
The logic of her approach to evaluating risk was so precautionary that virtually nothing could provide sufficient proof of safety while pretty much anything could provide sufficient proof of danger.
Right. And it is the potential danger of non-scientific “approaches” like Swan’s – including fabricating metrics like “anogenital distance,” over-valuing minor correlations, and placing unsubstantiated, theoretical op-eds in major newspapers – that fairness can be thwarted in our justice courts as well as in the court of public opinion.
It should be noted that such “methods” and “research” can also lead to unnecessary and costly EPA regulations that don’t make us one bit safer. Dr. Swan sure seems to be playing fast and loose with our tax dollars, which is the real source of the $5M in funding for her “research.”
