The risk and frequency of toxic chemical exposures in pregnant women is growing as scientific study and government policies are struggling to keep up.
For every American, roughly 30,000 pounds of chemicals are manufactured each year.
The number of new chemicals created each year also continues to grow — an estimated 2,000 are introduced every year.
In pregnant women, these chemicals may pose a threat not only to them, but to their unborn babies as well.
There are currently regulations and tests for many widely-used chemicals, but the potentially adverse effects of novel chemicals present a growing threat.
While many chemicals may be safe — after all, even water is a chemical — untested new chemicals may pose a risk or at least draw concern.
Fortunately, a group of researchers at the University of California San Francisco have developed a new method of screening for chemical exposures that could help shape policy and clinical practice.
In the new research, published in the journal Environmental Health Perspectives, the researchers demonstrated a proof-of-concept of their screening test on pregnant women.
The team looked for 700 chemicals including environmental organic acids (EOAs), which are widely used in pesticides and consumer products like bisphenol-A.
The team found that all of the women studied had detectable levels of some suspect chemicals in their blood.
Among a cohort of 75 pregnant women, they found that on average, a blood sample from each woman tested positive for 56 chemicals. Six of the chemicals discovered were novel, meaning that little is known about their effects on a mother and child in utero.
“The goal of the research is two-fold. One is to advance a technology that will better help us measure or scan for industrial or environmental chemical exposure in blood samples,” said Professor Tracey Woodruff, PhD, director of the Department of Obstetrics, Gynecology, and Reproductive Sciences at UCSF and co-author of the study.
“This was a proof-of-concept study that we are applying to pregnant women because pregnancy is a time when both the mom and the fetus are more vulnerable to effects from toxic chemical exposure.”
Testing positive for these chemicals doesn’t mean that either mother or infant will experience ill health effects, but it helps researchers better understand risks during this vulnerable time.
Dr. Ken Spaeth, chief of environmental medicine at Northwell Health in New York, said this new approach to testing is “really important.”
“There are so many sources of chemicals and so many ways that they can get into us, it’s a real challenge to try to understand the extent to which humans are being exposed to these environmental hazards,” said Spaeth.
“Approaches like this are much more comprehensive and allow for an ability to capture, to a much greater extent, the array of harmful substances, or potentially harmful substances, that we are carrying around in us.”
Spaeth pointed out that doctors are particularly concerned about pregnant women and how substances can affect fetal development.
“In a study like this where the focus is in pregnant women, it becomes all the more pressing and concerning because fetal development is the most vulnerable time in human development over the human life course,” said Spaeth.
How often are we exposed to toxic chemicals?
There’s a wide variety of toxic chemicals in the environment that are encountered on a daily basis — everything from paint and solvents to cleaning products and plastics.
Chemicals can be absorbed into the body and bloodstream through breathing in air pollution or ingesting toxins and pesticides in food. Even simply coming into contact with certain chemicals is enough to be absorbed by the skin.
Depending on the amount of time and amount of chemical that a person is in contact with, they may have their health affected or may have no discernable effects from this exposure.
Some of these chemicals are known to produce birth defects, IQ loss, and behavioral disorders in large enough quantities.
However, current screening methods tend to focus on a narrow range of chemical exposures.
“The current approach or what’s traditionally been done in the past is a good approach, but it needs to be augmented. First, we determine what chemicals do we think people are exposed to and then develop a method for that,” said Woodruff, “The problem is that there are a lot of things that we don’t have information about.”
She notes phthalates, for example, a chemical found in plastics that’s known to disrupt the endocrine system. It wasn’t originally screened for by the Centers for Disease Control and Prevention (CDC), but, “they discovered it kind of ‘accidentally’ and it turns out everyone is exposed to it.”
Part of the problem is that the production of new chemicals vastly outpaces the regulations intended to keep the public safe.
Bisphenol-A (BPA), for example, is a chemical widely used in canned and bottled foods and beverages. It’s known to harm the female reproductive system, but it isn’t federally regulated.
Some states, such as California, have enacted their own regulations for BPA.
Other chemicals like 1,4-dioxane, an industrial solvent that the EPA classifies as “likely to be carcinogenic in humans,” was recently discovered in water samples that affect 90 million Americans.
There’s still no federal standard for dioxane levels in water, although some states have enacted their own.
What about brand new chemicals?
As for novel chemicals, there’s little known about their health effects.
“We’re operating in the dark about exposures and health effects. We want to use the science to advance our ability to identify and prevent these harmful chemical exposures,” said Woodruff.
She hopes that the research and screening method developed by her team will help create more dialogue between patients and doctors about the risks of environmental chemical exposures, but stops short of recommending chemical screening as part of a standard pregnancy panel.
“We want to see this more integrated into the health-sciences community on the research side,” she said. “Eventually I think there will be work to look at ways to do screening, but again the screening piece is kinda at the end of the pipeline.”
“Really what we want to see are ways to prevent these exposures from happening before they reach someone who is pregnant because in some ways that’s too late,” she adds.
Instead she recommends that pregnant women, and all individuals, work toward limiting their exposures as much as possible.
The UCSF Program on Reproductive Health and the Environment recommends the following:
- Be a smart consumer and familiarize yourself with nontoxic products, including children’s toys.
- Sweep and mop regularly, as many toxic substances are present in dust.
- Clean with nontoxic products.
- Properly dispose of toxic substances.
- Avoid cigarette smoke and alcohol.
- Choose plastics responsibly and learn about BPA and phthalates.
A more comprehensive list can be found at the USCF website.