In utero exposure to plastic chemicals tied to developmental problems in toddlers
Israeli researchers find that higher levels of ubiquitous phthalates in the urine of pregnant mothers correlate with emotional and social difficulties in boys — but not girls
Renee Ghert-Zand is the health reporter and a feature writer for The Times of Israel.
It’s hard to avoid phthalates, a group of chemicals that make plastic soft and flexible, in our daily lives. Phthalates are in so many things we use: food containers; shampoo and beauty and skin care products; building and gardening materials; faux leather fashion and furniture upholstery; medical devices; toys; backpacks and purses; and home accessories like polyvinyl chloride (PVC) shower curtains. The list goes on and on.
These endocrine-disrupting chemicals (EDCs) enter our bodies by way of ingestion, inhalation, and absorption through the skin.
A new Israeli study by researchers from the Braun School of Public Health and the Department of Psychology at the Hebrew University of Jerusalem adds to the literature pointing to the association between prenatal exposure to phthalates and later neurodevelopmental and behavioral problems.
While other studies have focused on school-age children, this new study, published in the peer-reviewed NeuroToxicology journal, sheds light on the potential consequences of prenatal exposure to phthalates on the development of toddlers aged 24 months.
It found that higher levels of metabolites of the phthalate known as DEHP (Di(2-ethylhexyl)phthalate) in pregnant women’s urine correlated with lower scores on social-emotional developmental assessments in their sons. Notably, there was no correlation with girls born to mothers with higher levels of DEHP in their urine.
“The truth is that it’s very difficult to avoid exposure [to phthatlates]. In our study, 98 percent of [the participating pregnant] women were exposed at some level,” said Prof. Ronit Calderon-Margalit, director of the Braun School of Public Health.
Over several years, the researchers recruited 600 Israeli women to provide spot urine samples between weeks 11 and 18 of their pregnancies. The urine was checked for phthalate metabolites, specifically DEHP, DiNP, and MBzBP.
The researchers succeeded in following up with 158 of the women for assessment of their offspring around their 2nd birthday. They used well-established maternal reporting methods for gathering information on the children’s emotional and behavioral development. These included the Child Behavior Checklist (CBCL), the Ages & Stages Questionnaire – Third Edition (ASQ-3), and the Home Observation for Measurement of the Environment (HOME) questionnaires.
The 2-year-old boys with higher prenatal DEHP exposure had more social skills difficulties, and were more emotionally reactive, anxious or depressed. They also had somatic complaints and were socially withdrawn.
Calderon-Margalit said that the result showing sex differences was interesting. Most studies have shown problems with boys, but one indicated that the problems were with girls exposed in utero to phthalates. All of this must be considered within a larger context in which the full picture of endocrine-disrupting chemicals’ effects on fetuses is not completely understood.
“First of all, we know that we have more developmental issues with boys in the first place. So maybe with such a small sample size, it was easier to [statistically] figure out the associations in boys but not in girls,” Calderon-Margalit said.
“We also saw differences between boys and girls in a study we did on birth outcomes. For example, we saw differences in head circumference. These sex differences could be partly a result of the effect of phthalates as endocrine-disrupting chemicals,” she added.
When asked what women can do to protect themselves and their unborn children from phthalate exposure, Calderon-Margalit said that they can try to be aware of what products contain the chemicals.
Israel, unlike Europe and the US, still lacks a regulatory framework for chemicals in consumer products, let alone an efficient system of enforcement. Currently, the matter falls under the Ministry for Economy and Industry, and there is no mechanism for cooperation with the Health Ministry and the Environmental Protection Ministry.
“Reading labels isn’t going to help because phthalates are usually never listed. So the safest thing to do is to buy products that are imported from countries that have good regulatory systems for these chemicals,” Calderon-Margalit said.
“The findings of our study are not really addressed to individuals. They are aimed at the regulators. It’s their responsibility to protect the population,” she added.