US-Based Filipino Scientist Proposes Biomonitoring of Endocrine Disrupting Chemicals (EDCs) in Pregnant Women

“There is a need for biomonitoring endocrine disrupting chemicals (EDCs) in pregnant women because there is a growing body of evidence that exposure to EDCs in the womb has long term health consequences.” – Dr. Roy Roberto Gerona, 13 May 2014, Quezon City.

A visiting Filipino scientist drew
public attention to environmental chemicals that are finding their way to human
bodies, especially among pregnant women who may pass these substances to their
budding fetuses through the placenta.

At a “Science Talk” held today to mark the Safe Motherhood Week, Dr. Roy Roberto
Gerona, who is a clinical toxicologist based at the Department of Laboratory
Medicine, University of California in San Francisco, USA, spoke about the
importance of determining such toxins in pregnant women and how environmental
biomonitoring can provide a window to the maternal-fetal unit.

Organized by the EcoWaste Coalition (a waste and pollution watchdog), Philippine
Pediatric Society (a professional association of pediatricians) and Arugaan (a
breastfeeding advocacy and support group), the “Science Talk” drew over 50
participants from the healthcare sector, the government and the civil society,
including community women.

Among these environmental toxins are endocrine disrupting chemicals, or EDCs,
that are structurally similar to endocrine hormones such as estrogen,
testosterone, insulin and thyroxine, and which can mimic and interfere with
their normal functions, Dr. Gerona explained.

These EDCs, Dr. Gerona said, comprise most consumer products as he cited bisphenol
A (BPA) in polycarbonate reusable drinking bottles, baby feeding bottles,
carbonless thermal papers, rust-protection resins in canned drinks and foods;
phthalates used as plasticizers in toys, medical devices, adhesives and glues,
enteric coatings of capsules; perfluorinated compounds (PFCs) in Teflon and
Scotchgard; polybrominated diphenyl ethers (PBDEs) used as flame retardants in
polyurethane foams, electronics, furniture, and textiles.  He added that
these EDCs are also found in some pesticides such as glyphosate (Roundup), DDT,
and atrazine.

“Endocrine hormones regulate the homeostatic (steady state) function of our
bodies, including reproductive health, cardiovascular health and digestive and
metabolic health, among others.  Thus, chronic exposure to
EDCs disrupts hormone action and is associated with various clinical endpoints
including higher predisposition to cancer, cardiovascular diseases, obesity and
metabolic syndrome,” he explained.

“Because the levels of hormones in our bodies are also quite low, low level
exposures to EDCs affect their function,” he pointed out.

“Because the correct balance of hormone levels is crucial at specific time points
in fetal development, the fetus is more vulnerable to the effects of EDCs,” he

“Pregnant women’s exposure to EDCs is transmitted to the developing fetuses in
their wombs through the placenta. Some EDCs and their metabolites (breakdown
products) cross the placenta,” he said.

Exposure of the fetus to EDCs during its development has been associated with
immediate pathological effects such as crytorchidism (undescended testicles)
and hypospadias (delayed penile shaft opening) or long-term
epigenetic effects manifested in higher predisposition to various clinical endpoints
such as diabetes, obesity, and cancer later in life, Dr. Gerona said.

Environmental biomonitoring, Dr. Gerona said, is the process of determining the
body burden of toxic substances and their metabolites in human samples such as
blood, urine, breast milk, etc.

This entails measuring the levels of environmental chemicals using modern analytical
instrumentation including gas chromatography- mass spectrometry (GC-MS) and
liquid chromatography- mass spectrometry (LC-MS), he explained.

At the “Science Talk,” Dr.  Gerona also spoke about “non-targeted analysis”
of EDCs and how newer LC-MS technologies can help in understanding
environmental toxins in pregnant women, including the identification of
previously unmeasured chemicals that can be of concern to the nascent fetus.


Additional Information on Non-Targeted
Analysis of EDCs:

Newer LC-MS
technologies such as quadrupole time-of-flight mass spectrometry (QTOF/MS)
allow chemical profiling of biological samples. Instead of just measuring a few
environmental chemicals in biological samples, QTOF/MS allows complete mass
spectrometric profiling of all potential chemicals in biological samples
simultaneously. Applying this technology to maternal serum and cord blood
facilitates profiling of all potential EDCs that are present in either
compartment. This also allows discovery of novel EDCs that needs to be
biomonitored in pregnant women which may be of considerable concern to the
developing fetus. The talk will provide pilot data on non-targeted analyses of
a group of EDCs in maternal serum and cord blood in a cohort of pregnant women
in Northern California.