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Recently, the European Food Safety Authority, a body charged with providing “objective scientific advice” to the European Parliament, delivered a report on the safety of bisphenol-A, a chemical that has been generating scare headlines in the U.S. over fears that it might be an endocrine disruptor.

These fears stemmed from the work of a handful of scientists who proposed that very low exposures to a chemical could, counter-intuitively, cause harm that wouldn’t be seen at higher doses. These scientists, principally Frederick vom Saal and Wade Welshons of the University of Missouri pointed to dozens of studies in proof of such effects; and, as the Globe and Mail reported, they and environmentalists

“suspect bisphenol A has its fingerprints all over the unexplained human health trends emerging in recent decades hinting at something going haywire with sex hormones, including the early onset of puberty, declining sperm counts, and the huge increase in breast and prostate cancer, among other ailments.”

But the European Food Safety Authority’s report concluded otherwise. In fact, it dismissed the evidence for low dose responses to bisphenol-A, and concluded that there was no risk from the chemical in terms of the kind of exposures people are exposed to in normal, daily life.

“The Panel considered that low-dose effects of BPA in rodents have not been demonstrated in a robust and reproducible way, such that they could be used as pivotal studies for risk assessment. Moreover, the species differences in toxicokinetics, whereby BPA as parent compound is less bioavailable in humans than in rodents, raise considerable doubts about the relevance of any low-dose observations in rodents for humans. The likely high sensitivity of the mouse to oestrogens raises further doubts about the value of that particular species as a model for risk assessment of BPA in humans.

And yet, despite describing our exposure to bisphenol-A as “one of the biggest public-health and scientific controversies in the world,” Globe and Mail reporter Martin Mittelstaedt only makes one passing reference to the EFSA report, saying it gave “the benefit of the doubt to the [chemical] industry on these disputes,” when, in fact, the panel rejected the scientific basis for the evidence that Mittelstaedt is so keen to press on his readers.

This is amazing, especially as the European Union, by virtue of adopting the precautionary principle, has a much stricter policy of risk assessment when it comes to potentially hazardous chemicals.

What’s even more disturbing is that Mittelstaedt is so convinced by vom Saal’s research that he fails to quote a single toxicologist on the plausibility of low dose effects (vom Saal, it should be noted, is a biologist; he is also the principal source for media accounts of low-dose risks). Considering that vom Saal is proposing something that challenges our normal understanding of toxicology, this omission simply adds weight to the sense that neither Mittelstaedt nor the Globe and Mail are interested in dispassionate journalism, let alone dispassionate scientific inquiry.

Indeed, instead of turning to a toxicologist (surely there is one or two employed by a Canadian University?), Mittelstaedt seeks a response from a plastic industry spokesman, which ensures that the article is “balanced” in principle if not in spirit (an industry spokesperson just doesn’t have the same rhetorical authority as a scientist appealing to scientific method).

And without that independent scientific perspective on vom Saal’s research, Mittelstaedt is incapable of reporting its limitations. In his last literature review of the evidence for low-dose effects, vom Saal appears to accept any study that found any result pointing to a risk from bisphenol A, no matter what the dosage or endpoint, and ignores any study that didn’t find a negative outcome.

There appears to be no attempt to analyze the negative studies for accuracy or applicability of method or results, or to see if the results of these studies cohere with each other in a way which points to some underlying causal mechanism, or to see if the results can be replicated.

Vom Saal also doesn’t appear to address, at a methodological or causal level, why there are disagreements between studies on different endpoints. Nor does he discriminate between studies that, for methodological reasons, have little or no relevance to human health.

There is also the problem that some of research vom Saal has engaged in on bisphenol-A could not be replicated by other scientists. And as John Gierthy notes in Testing for Endocrine Disruption: How Much is Enough? “there is considerable controversy over the existence and/or relevancy of these low dose estrogen effects.”

On the other hand, Mittelstaedt allows vom Saal is to denigrate the research that contradicts his own position as “flawed,” or industry-funded, or conducted using the wrong kind of rat – even though some of the research finding no risk was conducted by Harvard’s Center for Risk Analysis.

In sum, it is hard to find an article on science and public health written by an ostensibly serious news paper in recent years where the reporter goes so far in supporting one particular scientist’s agenda as to systematically avoid or discount a massive body of contradictory research based on mainstream toxicological principles and regulatory practices. It is as if an article denying global warming was sourced entirely to a couple of skeptics, who claimed that they had lots of evidence, and the contrasting scientific consensus was dismissed as flawed – or giving the benefit of the doubt to the environmentalists.

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