A recent study has been grabbing headlines with the claim that health issues related to chemical exposure could be costing the U.S. around $340 billion annually. How does that study hold up to scrutiny?
The analysis, released this week in The Lancet Diabetes & Endocrinology, estimated healthcare and lost work costs from 15 medical conditions that research has linked to toxic chemical exposure.
In particular, the research zeroed in “endocrine-disrupting” chemicals including BPA; phthalates; polychlorinated biphenyl (PCB)-like polybrominated diphenyl ethers found in flame retardants; and pesticides like organophosphates.
The study, which was conducted by a team of researchers at NYU Langone Medical Center, then linked exposure to those chemicals to medical issues such as diabetes, obesity, endometriosis, certain cancers, diminished IQ scores, male infertility and birth defects.
Yet, Dr. Joseph Perrone, chief science officer for the Center for Accountability in Science, says the research used to justify the links between these conditions and chemical exposure was cherry-picked.
“The issue here is: What data did they put into this model to arrive at these conclusions? They didn’t do their own studies — they did a literature search,” he explains. “All the papers they pulled out are ones that said ‘These chemicals caused these diseases,’ which by virtue excludes studies that say that these chemicals do not cause these diseases.”
The American Chemistry Council also criticized the study in a released statement that questioned the researchers’ base assumptions.
“The authors have previously conceded that many of the chemicals they cite do not meet the World Health Organization’s widely-embraced definition of an endocrine-disrupting chemical. Instead, they implicate substances that have been shown to interact with the endocrine system similar to the way in which Vitamin D, cocoa and caffeine naturally do,” the ACC statement said.
Perrone also takes issue with how the presence of chemicals was measured in the sample the researchers used.
To measure exposure limits in the population, the study looked at blood and urine samples from a National Health and Nutritional Examination Survey that has been tracking about 5,000 participants since 1999.
But Perrone says that study may have only measured the presence of certain chemicals like BPA at one point during the last few decades, which isn’t necessarily a good predictor for health outcomes.
“If at one point they drank from a plastic bottle and had a higher level of BPA for example, that may not having bearing on whether or not they got cancer later,” Perrone says.
The study concludes by suggesting that people try to limit their exposure to “endocrine-disrupting” chemicals by avoiding plastics and switching to all natural or fragrance-free cosmetics.
And although Perrone calls the research “skewed” he says that exploring the impact of toxic chemicals on human health is a “worthwhile exercise,” and something “the industry is always on the watch for.”