Epidemiologists Make Liars Out of Regulators

What they say is safe isn't

Phthalates

Phthalates

Epidemiologists make liars out of regulators. I’m always being told, well, you know, the Food and Drug Administration has a guideline for this or regulation for that, and we’re all protected, you know? All these hidden chemicals in products to which I am being exposed all fall within someone’s regulations or guidelines.

I don’t believe any of it.

Epidemiologists are telling a very different story about what is happening to our bodies under the influence.

I think one of the most important fallacies has to do with what our group is finding in cosmetics. It’s some of the most disturbing and disheartening information about toxicity we’ve uncovered, and it’s only getting deeper and darker. It’s really not very pretty at all.

Our group has been studying the totality of exposures from cosmetics, and then comparing these findings with what regulators say and then what the human-based population studies tell us.

Things aren’t adding up for the nation’s health.

I truly fear for the health of subpopulations of persons who are getting the most cosmetic exposures. The studies of people themselves are of what we ordinarily experience. The regulations are all theory. Our exposures are reality. It’s very clear that persons who work in the cosmetics industry from nail salons to barbershops and even behind the counter in fragrance departments or cosmetic stores are experiencing exposures that are putting their health and the health of their children at serious risk of harmful developmental effects on the brain, on the eggs, on the sperm, on the anatomy of what it is to be male and female. All this is really happening right beneath the skin.

This comes clearly to mind with the phthalates. Our group is regularly finding members of this family in cosmetics. None of the levels violate any law. They are all within the guidelines. The trouble about these guidelines is that phthalates imitate the hormone estrogen, and we’re discovering, thanks to epidemiology, their effects are occuring at exposures to our bodies measured in the parts per billion.

But if that’s so and everything is so safe, why do we keep discovering that the children of parents with the highest exposures are being denied their full human potential?

Epidemiologists have found evidence linking pregnant women’s everyday exposures to phthalates to altered cognitive outcomes in their infants.

Most of the findings involved slower information processing among infants with higher phthalate exposure levels, with males more likely to be affected depending on the chemical involved and the order of information presented to the infants. Reported in the journal Neurotoxicology, the study is part of the Illinois Kids Development Study, which tracks the effects of hormone-disrupting chemicals on children’s physical and behavioral development from birth to middle childhood. Now in its seventh year, IKIDS has enrolled hundreds of participants and is tracking chemical exposures in pregnant women and developmental outcomes in their children.

IKIDS is part of a larger initiative funded by the National Institutes of Health, the Environmental Influences on Child Health Outcomes program. It is tracking the impact of prenatal chemical exposures and maternal psychosocial stress on children's growth and development over time. They measure numerous birth outcomes, including birth weight and gestational age. They assess infant cognition by studying their looking behavior. This allows them to get measures of working memory, attention and information-processing speed.

The researchers analyzed metabolites of three commonly occurring phthalates in urine samples regularly collected from the pregnant women in the study. The chemical exposure data were used in combination with assessments of the women's infants when the children were 7.5 months old.

The researchers used a well-established method that gives insight into the reasoning of children too young to express themselves verbally: infants typically look longer at unfamiliar or unexpected images or events.

The team used an infrared eye-tracker to follow each infant’s gaze during several laboratory trials. With the infant sitting on a caregiver’s lap, researchers first familiarized the child with two identical images of a face. After the infant learned to recognize the face, the researchers showed that same face paired with an unfamiliar one.

“In repeated trials, half of the 244 infants tested saw one set of faces as familiar, and half learned to recognize a different set of faces as familiar,” said Susan Schantz, a neurotoxicologist and professor emerita of comparative biosciences at the University of Illinois Urbana-Champaign. By analyzing the time spent looking at the faces, they could determine both the speed with which the infants processed new information and assess their ability to pay attention.

The assessment linked pregnant women’s exposure to most of the phthalates that were assessed with slower information processing in their infants, but the outcome depended on the specific chemical, sex of the infant and which set of faces the infant viewed as familiar. Male infants, in particular, tended to process information more slowly if their mothers had been exposed to higher concentrations of phthalates known to interfere with androgenic hormones.

“Most previous studies of the relationship between prenatal exposure to phthalates and cognition have focused on early and middle childhood,” Schantz said. “This new work suggests that some of these associations can be detected much earlier in a child's life.”

References

Kelsey L.C. Dzwilewski, Megan L. Woodbury, Andrea Aguiar, Jessica Shoaff, Francheska Merced-Nieves, Susan A. Korrick, Susan L. Schantz. Associations of prenatal exposure to phthalates with measures of cognition in 7.5-month-old infants. NeuroToxicology, 2021; 84: 84 DOI: 10.1016/j.neuro.2021.03.001

comments powered by Disqus