Exposure to phenols—chemicals used in a variety of consumer products and industrial processes that can disrupt hormones—during pregnancy was associated with changes in patterns of infant non-nutritive suck, according to ECHO Cohort research led by Megan Woodbury, PhD and Emily Zimmerman, PhD, CCC-SLP of Northeastern University, and Andréa Aguiar, PhD of University of Illinois Urbana-Champaign.
Non-nutritive sucking is a common behavior during infancy where a baby may suck on an object that cannot provide nutrients, such as a pacifier. Non-nutritive sucking is characterized by bursts of sucking separated by pauses to breathe. Researchers can measure the frequency, speed, and strength of non-nutritive sucking. Because sucking is a behavior present from birth that is controlled by neurons in the brainstem, it is an ideal indicator of early brain development.
During the study, researchers measured phenol exposure by analyzing phenol levels in maternal urine samples collected during pregnancy. Non-nutritive sucking was evaluated in 1- to 8-week-old infants using a custom pacifier for approximately 5 minutes.
Key takeaways include:
- Exposure to Bisphenol F, a common alternative to Bisphenol A or BPA found in some food packaging, was related to a lower non-nutritive suck frequency.
- Exposure to Triclosan, an antimicrobial chemical found in some soaps, was associated with a higher non-nutritive suck frequency.
- Exposure to other phenols used as preservatives and industrial processes (propylparaben, 2,4-dichlorophenol, and 2,5-dichlorophenol) was associated with weaker non-nutritive suck.
- Exposure to some phenols used in sunscreens and industrial processes (benzophenone-3, 2,4-dichlorophenol, and 2,5-dichlorophenol) was related to more non-nutritive suck bursts per minute.
- Propylparaben, a chemical used in some preservatives, was associated with more non-nutritive sucking per burst.
Previous studies linking changes in non-nutritive suck patterns to other exposures, such as maternal pregnancy stress and prenatal phthalate exposures, have also linked these exposures with decreased cognitive function in infants. The reasons these associations occur in the body are unknown but may be linked to hormone disruption during pregnancy.
“This study provides additional evidence that exposure to phenols may be related to developmental outcomes in children, demonstrating the need for continued research into how exposures during pregnancy impact infant health and development,” said Dr. Woodbury.
This collaborative research, titled “Examining the association between prenatal Phenol exposure and infant non-nutritive suck in two ECHO Cohorts,” was published in Environmental Epidemiology.