Viewpoint: ‘Health impact of chemicals doubled in last 5 years’? Gullible media misreporting flawed studies mislead the public

Geoffrey Kabat | August 19, 2020

This article or excerpt is included in the GLP’s daily curated selection of ideologically diverse news, opinion and analysis of biotechnology innovation.  Plastics and pesticides: Health impacts of synthetic chemicals in US products doubled in last 5 years, study finds,” a July 22 CNN headline announced to the world. Referring to a paper recently published in the journal Lancet Diabetes and Endocrinology, the media outlet told its readers in no uncertain terms what’s at stake:

The proof is piling up: Many synthetic chemicals can harm your health and that of your children. Evidence has doubled in the last five years about the negative impact on our health of endocrine-disrupting chemicals in plastics, pesticides, flame retardants and other merchandise….

“It’s a global problem,” the paper’s senior author told CNN. “These are chemicals used in consumer products all across the world.”...............

In fact, the astounding claim that the “health impact of synthetic chemicals in US products” has doubled in the space of five years is in no way supported by the Lancet analysis. The media coverage of the paper, and indeed the paper itself, are part of a decades-long trend among some scientists and activists to amplify the risk of exposure to chemicals in consumer products far beyond what can be justified by the evidence..............

A key fact that the review authors failed to acknowledge anywhere in their paper is that most of the exposures reported in the studies they examined add up to trace amounts of the various compounds. That is, they can be detected with sophisticated analytical techniques but are below the level where they are likely to cause any harm.  This poses a problem for epidemiologic studies..........While focusing on trace chemical residues, studies investigating EDCs often fail to account for the many lifestyle factors that have documented health effects and are likely to dwarf the possible impacts of EDCs................

This conclusion deserves careful scrutiny for many reasons, the most important being that the Lancet review and the new JAMA Network Open study failed to acknowledge that BPA has been the subject of extensive, high-caliber research over the past two decades. This research has demonstrated that human exposure to BPA is extremely low and that the compound is efficiently metabolized and excreted in urine, even in infants. Furthermore, BPA’s estrogenic potency is orders of magnitude lower than that of the natural hormone estradiol.

In their introduction, the authors of the Lancet paper referred to DDT, an insecticide whose indiscriminate use following World War II gave rise to the environmental movement in the 1960s. But the DDT experience also provides a cautionary tale, which they failed to mention.
In 1993 an early epidemiologic study reported that, compared to women with relatively low blood levels of a DDT metabolite, women with relatively high levels had a three-fold increased risk of developing breast cancer. The results were widely publicized and generated intense concern among women. However, when a large number of further studies were done, their results consistently failed to support the existence of an association............To Read More....