- Phthalates, which manufacturers commonly add to plastics, have been the subject of much research over the last 2 decades.
- Experts consider several phthalates to be endocrine disruptors and reproductive toxicants.
- According to a recent study, phthalates may negatively affect hormones that the placenta produces during pregnancy.
Phthalates are commonly used synthetic chemicals in plastics and personal care items.
The Consumer Product Safety Improvement Act of 2008 limited the use of a handful of phthalates in many household products, especially those that children use. However, these chemicals and many others like them are still present in everyday goods.
The placenta produces corticotropin-releasing hormone (CRH), the level of which increases throughout the course of pregnancy. The brain also produces CRH as part of the body’s stress response.
During pregnancy, the level of placental CRH is
However, when CRH levels are excessively high or rise rapidly earlier in pregnancy, issues such as preterm birth, fetal growth problems, high blood pressure, gestational diabetes, or postpartum depression may result.
The recent study was one of the first to examine the effect that phthalates have on placental CRH. Study co-author Emily Barrett, Ph.D., associate professor of biostatistics and epidemiology at the Rutgers School of Public Health in Piscataway, NJ, spoke with Medical News Today.
Barrett explained that scientists “have spent many years learning about how exposure to phthalates in humans impacts fetal development and, by extension, children’s health.”
“In fact,” she continued, “we’ve shown that prenatal phthalate exposure appears to increase the odds of preterm birth and, after birth, [phthalates] may alter growth, neurodevelopment, and more. These effects may be through changes in key hormones like testosterone, estrogens, and thyroid hormones.”
“What stimulated our interest in this topic was that we recognized a gap in the literature. No one had looked at whether phthalates interfere with corticotropin-releasing hormone.”
The Conditions Affecting Neurocognitive Development and Learning in Early Childhood study, or CANDLE, recruited 1,018 pregnant women receiving prenatal care at selected clinics in Shelby County, TN, from 2001 to 2011.
The researchers collected urine samples from each participant during two prenatal visits. One visit occurred at 16–29 weeks gestation and the other at 22–39 weeks. They measured urinary phthalate metabolites to assess phthalate exposure.
The team found that the presence of various phthalates was associated with higher placental CRH levels in mid-pregnancy and a drop in CRH levels later in the pregnancy.
The hormone levels were highest in the women who developed pregnancy complications, such as gestational diabetes and high blood pressure.
“Women with pregnancy complications, like preeclampsia and gestational diabetes, seemed to be most impacted by these chemicals,” Barrett told MNT.
“These are women who are already at heightened risk for poor outcomes for themselves and their children, and our results suggest they may be particularly vulnerable to these chemical exposures.”
– Emily Barrett, Ph.D.
The authors list several strengths and limitations of the study. The most notable strength was the large number of participants, of whom more than half were Black women. People of Color are
Limitations include the fact that the researchers only tested each woman twice during their pregnancy. Also, some phthalates are
MNT asked Katrina Korfmacher, Ph.D., a professor of environmental medicine at the University of Rochester Medical Center, NY, for practical tips to limit exposure to phthalates and other potentially harmful chemicals.
Korfmacher notes that people are often concerned about the difficulty of finding products that do not contain questionable chemicals or the potentially high costs of these products.
She recommends a free phone app called Detox Me. This app allows users to scan the barcodes of products to determine whether phthalates or other potentially harmful chemicals are present. Silent Spring Institute, which offers a wealth of information and tools for concerned consumers, developed the app.
“I recommend this tool because it is research-based and communicates the results of that research in a way women can use easily in selecting products for themselves or their families,” said Korfmacher.
Korfmacher further stressed: “Trying to protect themselves and their babies shouldn’t be left entirely to people who are pregnant and have limited financial means. We should all be looking at policy choices to help remove harmful chemicals from the product stream so that everyone is protected.”