Chemicals in Pregnant Women and Their Babies

April 19, 2021

A recent analysis of blood samples from pregnant women and the cord blood of their babies revealed 109 chemicals, including 55 previously not found in humans and 42 “mystery” chemicals whose sources and uses are unknown. 

A group of scientists at UCSF (University of California San Francisco) have recently detected 109 chemicals in a study of pregnant women, including 55 chemicals never before reported in people and 42 “mystery chemicals,” whose sources and uses are unknown. The chemicals, which most likely come from consumer products or other industrial sources, were found both in the blood of pregnant women, as well as their newborn children, suggesting they are traveling through the mother’s placenta.

New study, which is entitled, “Suspect Screening, Prioritization, and Confirmation of Environmental Chemicals in Maternal-Newborn Pairs from San Francisco, was revised and published in “Environmental Science & Technology”.

The 109 chemicals researchers found in the blood samples from pregnant women and their newborns are found in many different types of products. For example, 40 are used as plasticizers, 28 in cosmetics, 25 in consumer products, 29 as pharmaceuticals, 23 as pesticides, three as flame retardants, and seven are PFAS toxic compounds, which are used in carpeting, upholstery and other applications. The researchers say that it’s possible there are also other uses for all of these chemicals. 

The researchers also report that 55 of the 109 chemicals they tentatively identified appear not to have been previously reported in people, and that 37 of these 55 have little to no information about their sources or uses.

Authors write: “Our proof-of-concept study develops a suspect screening workflow to identify and prioritize potentially ubiquitous chemical exposures in matched maternal/cord blood samples, a critical period of development for future health risks. … We tentatively identified 73 suspects through fragmentation spectra matching and confirmed 17 chemical features (15 unique compounds) using analytical standards. We tentatively identified 55 compounds not previously reported in the literature, the majority which have limited to no information about their sources or uses.”

The scientific team used high-resolution mass spectrometry (HRMS) to identify human-made chemicals in people.  But, while these chemicals can be tentatively identified using chemical libraries, they need to be confirmed by comparing them to the pure chemicals produced by manufacturers that are known as “analytical standards.” And manufacturers do not always make these available.

“These new technologies”, said co-lead author Dimitri Panagopoulos Abrahamsson, PhD, “are promising in enabling us to identify more chemicals in people, but our study findings also make clear that chemical manufacturers need to provide analytical standards so that we can confirm the presence of chemicals and evaluate their toxicity”.

Lead-author Tracey J. Woodruff, PhD, MPH, a professor of obstetrics, gynecology and reproductive sciences at UCSF, declared: “These chemicals have probably been in people for quite some time, but our technology is now helping us to identify more of them. It is alarming that we keep seeing certain chemicals travel from pregnant women to their children, which means these chemicals can be with us for generations. It’s very concerning that we are unable to identify the uses or sources of so many of these chemicals. EPA must do a better job of requiring the chemical industry to standardize its reporting of chemical compounds and uses. And they need to use their authority to ensure that we have adequate information to evaluate potential health harms and remove chemicals from the market that pose a risk.”

Full Study “Suspect Screening, Prioritization, and Confirmation of Environmental Chemicals in Maternal-Newborn Pairs from San Francisco”
UCSF Press Release