STATS ARTICLES 2006
Time’s Toy Reporting Scares Parents
Trevor Butterworth, December 13, 2006
But is it ethical to publish a one-source tip sheet for parents when the source can’t prove a risk?
Errata: Margot Roosevelt of Time pointed out that the article that this story refers to is a sidebar to a longer, more balanced article in the magazine. However, our Google news alert demarcated it as a separate story on Time.com. This does not alter the criticism of this particular piece, which is that Time's advice to readers is one-sided. We have altered the article to reflect criticism of the sidebar as a separate story, and appended comment on the longer piece at the end.
Imagine you have to report on a potential health risk. What would you do if you found that every regulatory body in the U.S. did not believe there was a risk; that no study had shown a risk to humans, or even a strong correlation between the thing that was supposedly risky and some actual harm or defect that occurred; that, overwhelmingly, researchers who had looked at the risk didn’t really see any risk, all things being equal; but that one scientist, nevertheless, believed that the risk was worth taking seriously?
Would you report the consensus, the lack of evidence, the position of the regulatory bodies, and note that there was one notable expert voice raised in dissent – or would you base a story entirely on the scientist challenging the consensus?
If the risk was global warming, you would probably go with the consensus. Scientists, for example, who disagree with the “hockey stick” theory of climate warming are largely personae non grata, except on the editorial pages of the Wall Street Journal. But when it comes to phthalates, you would do as Time.com has just done, and ignore the consensus in favor of the minority viewpoint in a sidebar article that offers practical advice to readers.
In “Tips for Safe Toys and other Household Products” Time magazine’s Margot Roosevelt passes on to readers “one expert’s advice on keeping kids healthy.”
The expert is Shanna Swan, “a University of Rochester epidemiologist and an expert on endocrine disruptors,” whose controversial paper on phthalates was widely misquoted by the media as claiming that baby boys who were exposed to several phthalates in utero had defective genitalia. Swan tells Time that
“Virtually all of us are regularly exposed to low levels of phthalates and BPA,"… The risks from these products have not been firmly established. But there are some measures we can take, until the use of these chemicals in everyday materials and products is more aggressively restricted."
Just what does “not firmly established” mean? It means, in fact, that the Consumer Product Safety Commission rejected a request from the Public Interest Research Group to ban phthalates in toys in 2003. THE CPSC looked at research on the way children mouthed toys and potential migration rates in the toys and concluded that there was no risk. The European Union risk assessment reached a similar conclusion.
But you would never know this from Time’s article. Nor would you know that Professor Swan appears to be less certain about how dangerous phthalates are than she was last January. As she wrote in an opinion piece for the San Francisco Chronicle,
“…children are also highly vulnerable long before they are even born. In-utero exposures to phthalates can lead to birth defects and genital malformations, as numerous studies have shown in laboratory animals and, as suggested most recently, in a study of baby boys.
A government-funded study I recently led in collaboration with scientists and physicians from several universities and the U.S. Centers for Disease Control and Prevention was the first to find a significant relationship between human exposure to phthalates and adverse changes in the genitals of baby boys.”
Professor Swan was criticized (by, among others, STATS) for drawing such controversial conclusions from her data. She, for instance, determined that the “adverse changes” related to a biomarker known as the anogenital index, which was shorter than average in the boys in her study.
But as no-one has determined what the normal range for the anogenital index is, and as none of the baby boys had defective genitals or showed evidence of any reproductive defects, the conclusion that something was awry was far from proven.
An independent review panel under the auspices of the National Toxicology Program, which examined her study in October 2005, went further, finding her research inconclusive, her data “insufficient,” and noting that the relevance of the anogenital distance “had not been established” in humans. The NTP panel recommended redoing the study with a larger sample size of children, as the kind of research Swan was doing was important.
Additionally, a recent EPA draft risk assessment of one phthalate, DBP, also noted that there were many limitations to Swan’s study.
As for bisphenol A (BPA), in 2004 Harvard’s Center for Risk Analysis convened a panel to evaluate the weight of evidence for low-dose reproductive and development effects of this chemical, which is widely used in plastic containers. The panel found that:
…“the weight of the evidence for low-dose effects is very weak. Studies are conflicting, the effects are subtle with questionable functional importance even if real, and there are conflicting data as to the proposed mode of action (i.e., whether BPA acts as an estrogen).”
The full analysis was published in the peer-reviewed journal “Human and Ecological Risk Assessment.”
Professor Swan could be a visionary when it comes to endocrine disruption and low-level exposure to environmental chemicals; but there is a serious question as to whether her sense of risk and her message of caution are warranted by the current state of the science. (In “Judging Science, Scientific Knowledge and the Federal Courts,” MIT Press, 1997, Kenneth Foster and Peter Huber were so critical of Swan’s precautionary reasoning in the case of the toxicological risks of Benedictin that they argued that her reasoning wasn’t actually scientific, and that she should not have been admitted as an expert witness in court.)
Journalists do not have to delve into the philosophical and legal grounds for what constitutes good scientific evidence when reporting a health scare (although it would help): basic reporting should be able to determine where consensus on the “best estimate” of risk lies according to the present state of the science, and where challenges to this consensus come from and how far they’ve gone in proving their case; but to ignore the former and warn the public solely on the basis of the latter is not merely a matter of inept reporting, it is bias of the worst kind in science journalism – and a profound disservice to public health.
Does Swan, then, deserve to be heard? Of course she does; but she doesn’t deserve to be the only voice heard when she has, in no uncertain terms, advanced an agenda that is blatantly at odds with the regulatory and risk assessment data. “Not firmly established,” to use Swan’s turn of phrase, turns out to mean “actually, far from being established.” A story that relies on her alone for its scientific content is dangerously unbalanced.
As a consequence of using Swan as the sole source for its "sidebar" article, Time blithely advises parents to throw out soft vinyl toys, teethers, pacifiers, nipples, sippy cups, baby bottles, among other health recommendations. Any parent who read this article could not but experience anxiety and even dread about his or her children’s health.
Which is why we urge Time to pull this extraordinarily bad example of health advice from its website – or better yet, to redraft it to show the full range of evidence for the chemicals in question.
*As for the "main story" - What's Toxic in Toyland: It does indeed note that the chemical and toy industries "hotly dispute" activist claims about the dangers of these chemicals. But it also makes claims about these chemicals that are not supported by independent risk assessments - or even by reading the studies cited in the piece. For example, Time states that:
"The controversy centers on a family of chemicals called phthalates (pronounced "thalates"), which are used to soften vinyl, and on bisphenol A (BPA), a substance used to make clear and shatterproof plastic. Most are known to be so-called endocrine disrupters, capable of interfering with the hormones that regulate masculinity and femininity. Several hundred animal studies have linked phthalates to prostate and breast cancers, abnormal genitals, early puberty onset and obesity. More recently, they've been shown to affect humans as well."
First of all, it is misleading to argue that these chemicals have been shown to cause these symptoms without noting the dosages involved: Just because there's an adverse effect at a high dosage doesn't mean there will be an adverse effect at a low dosage. As the Harvard Center for Risk Analysis noted , they could not find any "consistent affirmative evidence of low-dose BPA effects for any endpoint" in rodents with respect to hormone-like effects. And the studies that found correlations between low dosages and negative effects in animal studies had less statistical power than the studies that did not find an association (these had larger sample sizes).
Time also mischaracterizes the major study on pthalates and humans
"In a paper published last year in the journal Environmental Health Perspectives, scientists from the Centers for Disease Control and Prevention and several universities found that boys born to mothers with higher phthalate levels are far more likely to show altered genital development, linked to incomplete testicular descent. "
First, only one of the authors is affiliated with the Centers of Disease Control - and she isn't the lead scientist on the study, that honor belongs to Shanna Swan. Interestingly, The National Toxicology Program, looking specificially at the phthalate DEHP, found that Swan did not show any statistical association between DEHP metabolites and genital development. This is important because DEHP is one of the phthalates found in baby toys. (For a detailed analysis of Swan's study on phthalates, check out STATS "Toy Tantrums.") The other phthalate in toys, DINP, has been deemed safe by both the Consumer Product Safety Commission and the European Union The latter's Institute for Health and Consumer Protection noted in 2003 that:
“The indirect exposure via the environment is unlikely to pose a risk to humans following the main route of exposure, the oral route… As combined exposure of adults is almost exclusively related to occupational exposure, the overall assessment indicates no concern for adults. For infants, combined exposure which is mainly related to exposure from toys and via the environment is not considered of concern.”
All of this is largely beside the point, alas; as STATS Rebecca Goldin concluded,
"Restricting the use of phthalates in toys is going to have virtually no effect on phthalate exposure. Neither will attempts to limit phthalates in cosmetics. Such measures will not reduce the main sources of our exposure to phthalates (since our main source is food). It will not reduce our exposure (or our children’s) to the particular phthalates that are correlated with short AGI even if we buy into the claim that this is a worthy goal."