ECHO Participants and Investigators Featured in The Washington Post

Posted on September 8, 2025 by Jodi Snare

The Washington Post recently featured the Environmental influences on Child Health Outcomes (ECHO) Program in a story on phthalates—chemicals commonly found in plastics and personal care products—and how they may affect babies’ development during pregnancy.

The article highlighted ECHO participants who are helping researchers understand how chemical exposures during pregnancy and throughout the life course may influence pregnancy outcomes and child health. ECHO participants Arica Nyamsi and Cassondra Perez shared a range of experiences with chemical exposures, from making significant lifestyle changes to expressing uncertainty and a need for clearer guidance.

Sheela Sathyanarayana, a professor of pediatrics at the University of Washington, explained that determining safe levels of phthalate exposure is challenging because individual health risks vary based on genetics and susceptibility.

The story also featured ECHO investigator Dr. Leonardo Trasande of NYU Grossman School of Medicine, who noted in the article:

“Endocrine-disrupting chemicals are one of the biggest global health threats of our time. And 2 percent of us know about it — but 99 percent of us are affected by it.”

Chemical exposures will be a focus at the ECHO Symposium: Translating Science to Action on September 15, 2025. During the first session, Dr. Trasande will discuss phthalate exposure in pregnancy and early childhood, focusing on the evidence, knowledge gaps, and opportunities to inform policies, practices, and programs. Mrs. Perez will also speak during the third session on her experience as an ECHO participant.

Learn more about ECHO’s ongoing research on chemical exposures. Also, review the full symposium agenda for details and register to attend this free event either in-person or virtually.

Exposure to Certain Flame-retardant Chemicals During Pregnancy May Be Associated with Behavioral Issues in Young Children

Posted on August 26, 2025August 26, 2025 by Jodi Snare

Exposure to certain organophosphate esters (OPEs)—chemicals commonly used as flame retardants and plastic softeners in a variety of household and industrial products—during pregnancy was associated with more behavioral issues in young children, according to a new ECHO Cohort study led by Jiwon Oh, PhD and Deborah Bennett, PhD of the University of California, Davis.

Previous research has linked exposure to OPEs during pregnancy with potential adverse effects on child brain development, but more evidence is needed. In this study, researchers investigated the association between prenatal exposure to OPEs and child behaviors. The study included 2,948 mother-child pairs from 12 ECHO Cohort study sites across the U.S., and the investigators used the Child Behavior Checklist for ages 1½–5 to assess each child’s behavior during early childhood.

Among the nine OPEs measured, diphenyl phosphate (DPHP) was detected in almost all pregnant women (99.5%) and had the highest median concentration. Other frequently detected OPEs included dibutyl phosphate/di-isobutyl phosphate (DBUP/DIBP), bis (1,3-dichloro-2-propyl) phosphate (BDCPP), bis(2-chloroethyl) phosphate (BCETP), bis(2-butoxyethyl) phosphate (BBOEP), and bis(1-chloro-2-propyl) phosphate (BCPP).

“This research builds on a growing body of evidence of potential harm caused by exposures to OPEs,” said Dr. Bennett.

Key Takeaways include:

Prenatal exposure to BBOEP (at moderate concentrations rather than high concentrations) was associated with more internalizing behaviors (e.g., anxiety, depression), externalizing behaviors (e.g., aggression, hyperactivity), and total behavior issues in young children.
Exposure to BCPP was associated with more externalizing behaviors and total behavior issues.
Detectable dipropyl phosphate (DPRP) was associated with fewer externalizing behaviors.
Boys showed more behavior issues associated with prenatal BDCPP and BCPP exposure.
Children from highly vulnerable neighborhoods—defined by community-level demographics, socioeconomic status, housing, access to transportation, and other factors—exhibited more behavior issues associated with prenatal BCPP exposure.

“While further research is needed, our findings suggest that reducing exposure to this chemical class during pregnancy may help mitigate emotional and behavioral problems in young children,” said Dr. Oh.

This collaborative research, titled “Prenatal Exposure to Organophosphate Ester Flame Retardants and Behavioral Outcomes in Early Childhood in the Environmental influences on Child Health Outcomes (ECHO) Cohort,” is published in Environment International.

Read the research summary.

Prenatal Exposure to Phthalates, But Not Alternatives, May Influence Children’s Behavior, ECHO Study Finds

Posted on August 26, 2025August 26, 2025 by Jodi Snare

Exposure to certain phthalates during pregnancy is associated with small to modest increases in behavioral issues, such as aggression and attention problems, in children aged 1.5 to 5 years, according to ECHO Cohort research led by Jiwon Oh, PhD and Deborah Bennett, PhD of the University of California Davis.

Researchers analyzed 27 phthalate and 6 alternative plasticizer metabolites in a large and diverse group of participants, exploring how these chemicals relate to both internalizing behaviors (like anxiety and depression) and externalizing behaviors (such as emotional reactivity, aggression, and attention difficulties).

The study found that higher levels of two specific phthalate metabolites—mono-benzyl phthalate (MBzP) and mono-hexyl phthalate (MHxP)—were connected to more externalizing behaviors, such as aggression or attention problems. However, these chemicals weren’t strongly linked to internalizing behaviors like anxiety or depression. The study also looked at a newer plasticizer called DINCH but didn’t find any effects on children’s behavior.

“While this study did not observe neurobehavioral impacts of the alternative plasticizer DINCH, a broader range of alternative plasticizers deserves attention due to their increasing use and potential neurotoxicity observed in laboratory studies,” said Jiwon Oh, PhD, of the University of California, Davis, who led the research.

The impact of these chemicals varied between boys and girls and depended on the neighborhood where the children lived. Some chemicals had stronger associations in kids from neighborhoods with more resources, while others were more impactful in areas with fewer resources.

These findings highlight the importance of understanding how prenatal exposure to widely used chemicals may affect early childhood behavior and underscore the need for further research on plasticizers that are used as replacements for phthalates.

This collaborative research titled “Prenatal exposure to phthalates and alternative plasticizers and emotional and behavioral outcomes in early childhood in the Environmental influences on Child Health Outcomes (ECHO) Cohort” is published in Environment International.

Read the research summary.

Exposure to Common Flame-retardant Chemicals During Pregnancy May Be Associated with Behavioral Issues in Young Children, ECHO Study Finds

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Exposure to Common Flame-retardant Chemicals During Pregnancy May Be Associated with Behavioral Issues in Young Children, ECHO Study Finds

Author(s): Jiwon Oh, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health supported this research.

Why was this study needed?

Organophosphate esters (OPEs) are chemicals commonly used as flame retardants and plastic softeners in a variety of household and industrial products, including furniture, electronics, infant products, and fabrics. Previous research has linked exposure to OPEs during pregnancy with potential adverse effects on child brain development, but more evidence is needed. In this study, researchers investigated the association between prenatal exposure to OPEs and child behaviors.

What were the study results?

Among the nine OPEs measured, diphenyl phosphate (DPHP) was detected in almost all pregnant women (99.5%) and had the highest median concentration. Other frequently detected OPEs included dibutyl phosphate/di-isobutyl phosphate (DBUP/DIBP), bis (1,3-dichloro-2-propyl) phosphate (BDCPP), bis(2-chloroethyl) phosphate (BCETP), bis(2-butoxyethyl) phosphate (BBOEP), and bis(1-chloro-2-propyl) phosphate (BCPP).

Prenatal exposure to BBOEP (at moderate concentrations rather than high concentrations) was associated with more internalizing behaviors (e.g., anxiety, depression, emotional reactivity), externalizing behaviors (e.g., aggression, inattention), and total behavior issues in young children. Exposure to BCPP was associated with more externalizing behaviors and total behavior issues. In contrast, detectable dipropyl phosphate (DPRP) was associated with slightly fewer externalizing behaviors. Boys showed more behavior issues associated with prenatal BDCPP and BCPP exposure. Children from highly vulnerable neighborhoods—defined by community-level demographics, socioeconomic status, housing, access to transportation, and other factors—exhibited more behavior issues associated with prenatal BCPP exposure.

What was the study's impact?

Use of OPEs is increasing, with widespread exposure observed in pregnant women. While further research is needed, this study suggests that reducing exposure to certain chemicals during pregnancy may help mitigate emotional and behavioral problems in young children.

Who was involved?

The study included 2,948 mother–child pairs from 12 ECHO Cohort study sites across the United States. Non-Hispanic White (40.2%), non-Hispanic Black (28.6%), and Hispanic (21.3%) mothers were included in the study. Most participating mothers (85.2%) did not experience major pregnancy complications and most of their children (93.2%) were born after at least 37 weeks of pregnancy.

What happened during the study?

During the study, researchers collected urine samples from pregnant participants and analyzed them for nine chemical markers of OPE exposure. Later, researchers assessed the child’s behaviors using the Child Behavior Checklist for Ages 1½–5. The researchers then used statistical methods to examine associations between each OPE exposure during pregnancy and behavioral issues in children. The study also evaluated how other factors, like the child’s sex and their social vulnerability, may have influenced the effect of prenatal OPE exposure on their behavior.

Footnote: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

What happens next?

Future studies could help researchers better understand the effects of prenatal OPE exposure on child brain development and determine whether reducing these exposures could be beneficial to children’s health and development.

Where can I learn more?

Access the full journal article, titled “Prenatal Exposure to Organophosphate Ester Flame Retardants and Behavioral Outcomes in Early Childhood in the Environmental influences on Child Health Outcomes (ECHO) Cohort,” in Environment International.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published August, 2025

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Exposure to Common Flame-retardant Chemicals During Pregnancy May Be Associated with Behavioral Issues in Young Children, ECHO Study Finds

Prenatal Exposure to Phthalates, But Not Phthalate Replacements, Linked to Children’s Behavior, ECHO Study Finds

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Prenatal Exposure to Phthalates, But Not Phthalate Replacements, Linked to Children’s Behavior, ECHO Study Finds

Author(s): Jiwon Oh, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health supported this research.

Why was this study needed?

Phthalates are widely used chemicals that make plastics more flexible. During pregnancy, these chemicals can cross the placenta and may affect brain development. Although exposure to some phthalates has decreased over the past two decades, these chemicals and their replacements—such as DINCH and DEHTP—are still common, and little is known about their effects on children’s brain development. In this study, researchers examined many chemicals that form when the body breaks down phthalates and other plasticizers to see if exposure to these chemicals during pregnancy might be associated with behavioral problems in young children, including emotional reactivity, anxiety, depression, aggression, and attention problems.

What were the study results?

Researchers found that higher levels of two phthalate metabolites, mono-benzyl phthalate (MBzP) and mono-hexyl phthalate (MHxP), during pregnancy were associated with small to modest increases in externalizing behaviors (aggression and attention problems) in children aged 1.5–5 years. They did not find strong links between phthalate exposure and internalizing behaviors (emotional reactivity, anxiety, and depression), or between prenatal exposure to the phthalate replacement DINCH and any behavioral outcomes. The impact of these chemicals varied between boys and girls and depended on the neighborhood where the children lived. Some chemicals had stronger associations in kids from neighborhoods with more resources, while others were more impactful in areas with fewer resources.

What was the study's impact?

The study suggests that prenatal exposure to certain phthalates, but not to the alternative chemical DINCH, may be associated with increased externalizing behaviors in young children.

Who was involved?

Participants included 2,617 mother–child pairs from 13 ECHO Cohort study sites. Children’s behaviors were assessed at ages 1.5–5 years, and maternal urine samples were collected mostly during mid- to late-pregnancy.

What happened during the study?

During the study, prenatal maternal urine samples were analyzed for 27 chemical markers of phthalate exposure and six markers of exposure to non-phthalate replacements. Later, the children's behaviors were assessed using the Child Behavior Checklist for Ages 1½–5 (CBCL/1½–5). The researchers then used statistical methods to explore how levels of specific chemicals in the pregnant women’s body were linked to behaviors like emotional reactivity, anxiety, depression, aggression, and attention problems, and whether these links differed by child sex and neighborhood opportunity.

Footnote: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

What happens next?

Future studies could show how much pregnant women are exposed to di-n-hexyl phthalate (the parent compound of MHxP) and its effects on children’s brain development across different populations. Researchers may also study how different newer plasticizers affect brain development by looking at more recent participants and testing samples taken from mothers at several stages during pregnancy.

Where can I learn more?

Access the full journal article, titled “Prenatal exposure to phthalates and alternative plasticizers and emotional and behavioral outcomes in early childhood in the Environmental influences on Child Health Outcomes (ECHO) Cohort,” in Environment International.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published August, 2025

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Prenatal Exposure to Phthalates, But Not Phthalate Replacements, Linked to Children’s Behavior, ECHO Study Finds

Young Children Show Widespread Exposure to Environmental Chemicals, ECHO Study Finds

Posted on July 24, 2025July 24, 2025 by Jodi Snare

Children had higher levels of certain replacement chemicals compared to their mothers during pregnancy.

Young children are exposed to a wide range of environmental chemicals, including some emerging and replacement chemicals, according to ECHO Cohort research measuring early childhood exposures. This study found that children aged 2 to 4 years often had higher levels of certain chemicals compared to their mothers during pregnancy, highlighting potential risks for future health.

Researchers measured 111 different chemicals in urine samples from 201 children and their mothers from six ECHO Cohort study sites across the United States. More than half of the children’s samples contained multiple chemicals, such as environmental phenols, pesticides, phthalates, and markers of exposure to polycyclic aromatic hydrocarbons (PAHs). Approximately 34 chemicals were found in over 90% of the samples, including nine of which have not been included in U.S. national biomonitoring.

Compared to their mothers, children showed higher levels of chemicals like bisphenol S (BPS), used in hard plastics and synthetic fibers, and compounds related to pesticides. By contrast, mothers had higher levels of chemicals such as triclosan and monoethyl phthalate (MEP), which are found in some soaps and cosmetics.

“Finding so many chemicals detected in over 90% of young children reinforces the concern that our children are being exposed to a sea of potentially harmful compounds from their earliest years, with little parents can do to protect them”, said Deborah Bennett, PhD of the University of California, Davis.

Over time, exposures to chemicals like triclosan, parabens, phthalates, and PAHs have become less common, likely due to regulations and bans. However, replacement chemicals such as DINCH—a phthalate substitute in some plastics—and certain pesticides have been increasingly detected.

This collaborative research, titled “Early Childhood Exposures to Environmental Chemicals in the Environmental influences on Child Health Outcomes Consortium,” is published in Environmental Science & Technology.

Young Children May Be Exposed to a Variety of Emerging Chemicals Found in Some Consumer Products

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Young Children May Be Exposed to a Variety of Emerging Chemicals Found in Some Consumer Products

Author(s): Jiwon Oh, Deborah H. Bennett, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health supported this research.

Why was this study needed?

Over time, exposure to chemicals like triclosan, parabens, phthalates, and PAHs became less common, likely because of new rules and bans on their use. However, replacement chemicals—like DINCH, a chemical that has replaced phthalates in some plastic products—and some pesticides have been showing up more often in later years. Exposure to multiple chemicals during pregnancy and early childhood is a concern because these are critical stages of development when children are more vulnerable to harm. Such exposures can increase their risk of health problems later in life. There is limited data tracking young children’s – 2 to 4 years - exposure to environmental chemicals compared to older children. Prenatal and early-life exposure to these chemicals can increase the risk of multiple adverse child health outcomes. This study aimed to investigate early childhood exposures to a variety of environmental chemicals.

What were the study results?

Scientists measured 111 different chemicals in urine samples from young children and their mothers during pregnancy. More than half of the samples contained chemicals such as environmental phenols, pesticides, phthalates, and chemical markers of exposure to polycyclic aromatic hydrocarbons (PAH). About 34 chemicals were found in over 90% of the total samples. Compared to their mothers during pregnancy, children had higher amounts of certain chemicals, like bisphenol S (BPS)—a chemical used in some hard plastics and synthetic fibers as a replacement for BPA—and pesticide-related compounds. On the other hand, mothers had higher levels of chemicals like triclosan and monoethyl phthalate (MEP), markers of exposure to chemicals found in some consumer products like soaps and cosmetics.

Certain groups of children, such as younger kids, later-born siblings, and those from families with fewer resources, were exposed to higher levels of chemicals.

What was the study's impact?

This study suggests that young children may be exposed to a variety of emerging and replacement chemicals that may affect their health later in life. Continued monitoring in larger populations of young children can help researchers better understand how these exposures affect children’s long-term health.

Who was involved?

The study included 201 children aged 2-4 years and their mothers recruited from six ECHO Cohort study sites across the United States.

What happened during the study?

Researchers collected urine samples from each child and their mother during pregnancy. These samples were analyzed for the levels of 111 different chemicals related to environmental exposures. The concentrations of these chemicals were compared between child and prenatal maternal samples. The researchers also examined social and environmental factors that may have influenced the concentration of each chemical in children's urine samples, such as race, ethnicity, maternal education, maternal age, and neighborhood opportunity.

Footnote: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

What happens next?

Additional studies tracking early childhood exposures to a variety of contemporary and emerging chemicals could help researchers better understand the potential effects these exposures may have on children’s short and long-term health.

Where can I learn more?

Access the full journal article, titled “Exposures to Contemporary and Emerging Chemicals Among Children Aged 2-4 Years in the United States Environmental Influences on Child Health Outcomes (ECHO) Cohort,” in Environmental Science & Technology.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published June 30, 2025

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Young Children May Be Exposed to a Variety of Emerging Chemicals Found in Some Consumer Products

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ECHO Researchers Investigate Association of Early Childhood Phthalate Exposures with ADHD Behaviors in Childhood and Adolescence

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ECHO Researchers Investigate Association of Early Childhood Phthalate Exposures with ADHD Behaviors in Childhood and Adolescence

Authors: Jiwon Oh, Julie B. Schweitzer, Deborah H. Bennett, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health, supported this research.

Why was this study needed?

Phthalates are widely used chemicals found in many everyday items such as food packaging, flooring, building materials, medicine coatings, medical supplies, cosmetics, and personal care products. When phthalates enter the body, they are metabolized and converted into various smaller molecules, known as metabolites.

Animal studies suggest that exposure to phthalates during early life may negatively affect the nervous system, but there has been limited investigation into potential associations between early childhood phthalate exposure and attention-deficit/hyperactivity disorder (ADHD) behaviors in later childhood and adolescence.

For this study, ECHO researchers wanted to investigate whether exposure to phthalates in children at ages 2-5 years was associated with ADHD symptoms when these children were ages 8-18 years.

Learn how to say phthalate.

What were the study results?

ECHO Cohort researchers evaluated the levels of several metabolites that result from phthalate exposure. They saw that in children ages 2-5 years, most of these molecules were not associated with ADHD behaviors in these children at ages 8-18 years.

However, among children who had been diagnosed with autism spectrum disorder (ASD), one of these metabolites—mono-2-heptyl phthalate (MHPP)—was associated with more ADHD behaviors. Among typically developing children, a different small molecule—mono-carboxy isooctyl phthalate (MCiOP)—was associated with more hyperactive/impulsive behaviors.

What was this study's impact?

This study suggests that early childhood exposure to certain phthalates may be associated with having both ASD and ADHD traits. Since ADHD behaviors are more commonly found in children with ASD, deepening the understanding of how exposure to environmental chemicals, such as phthalates, could contribute to this comorbidity may be important for managing and treating these conditions effectively.

Note: The results reported here are from a single study. Other or future studies may provide new information or different results. You should consult with a qualified healthcare provider for diagnosis and for answers to your personal questions.

Who was involved?

This study included 243 children living in Northern California and taking part in the ReCHARGE (Revisiting Childhood Autism Risks from Genetics and Environment) study. This study included both neurotypical and neurodiverse children, with about 60% of them having ever had neurodevelopmental concerns. Therefore, the children included in the study tended to have more ADHD behaviors compared with children in the general population.

What happened during the study?

Phthalate metabolites can be measured in biological samples, such as urine, to assess exposure to phthalates. In this study, the researchers measured 15 phthalate metabolites in urine samples of young children ages 2-5 years. Parents answered questions about each child’s ADHD symptoms at ages 8-18 years.

What happens next?

While the metabolite MHPP and the phthalate it’s derived from, di-n-heptyl phthalate (DHPP), are commonly found in children’s urine, their influence on neurodevelopment has not been studied as much as other phthalates. Since exposure to DHPP has been linked to problems with development and behavior in animals, further studies need to look more closely at this compound to understand its effects on how the brain develops in children.

Where can I learn more?

Read the full research article, titled “Early childhood exposures to phthalates in association with attention-deficit/hyperactivity disorder behaviors in middle childhood and adolescence in the ReCHARGE study,” in the journal International Journal of Hygiene and Environmental Health.

Learn more about ECHO’s other chemical exposure research.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published June 2024

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ECHO Researchers Investigate Association of Early Childhood Phthalate Exposures with ADHD Behaviors in Childhood and Adolescence

ECHO Cohort Study Finds Association Between PFAS and Bioactive Lipids

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ECHO Cohort Study Finds Association Between PFAS and Bioactive Lipids

Authors: Himal Suthar, Max Aung, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of the Director, National Institutes of Health supported this research.

Why was this study needed?

Per- and polyfluoroalkyl substances (PFAS) are a large, complex group of synthetic chemicals that have been used in consumer products around the world since about the 1950s. They are ingredients in various everyday products. For example, PFAS are used to keep food from sticking to packaging or cookware, make clothes and carpets resistant to stains, and create firefighting foam that is more effective. People are most likely exposed to these chemicals by consuming PFAS-contaminated water or food, using products made with PFAS, or breathing air containing PFAS.

Because PFAS break down slowly, if at all, people and animals are repeatedly exposed to them, and blood levels of some PFAS can build up over time. Scientific studies have identified multiple health effects associated with PFAS exposure.[1] Women exposed to PFAS during pregnancy are at increased risk for adverse birth outcomes and pregnancy complications.

Lipids are fatty molecules that perform a variety of functions in the body—from forming the membranes of cells to serving as a building block for certain hormones. Changes in bioactive lipids—broadly defined as a category of lipids with signaling properties that cause biological effects and changes in the body—have been linked to PFAS exposure and adverse pregnancy outcomes. This study aimed to compare the concentration of PFAS in the blood of pregnant participants with levels of bioactive lipids in three important metabolic pathways.

[1] National Institute of Environmental Health Sciences: Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS) (nih.gov)

What were the study results?

The research team analyzed the associations between 12 types of PFAS, in pairs and as mixtures, and 50 bioactive lipids in blood plasma in pregnant participants across three ECHO Cohort Study Sites. When researchers looked at data from different study sites, they found that higher levels of PFAS in blood were often linked with higher levels of certain bioactive lipids. The research team also noticed differences in the distribution of bioactive lipid compounds between individual study sites, possibly driven by variations in the genetic makeup and sociodemographic characteristics of the populations or differences in environmental exposures due to diet.

Footnote: Results reported here are for a single study and reflect an observed correlation. Other or future studies may provide new information or different results. You should always consult with a qualified healthcare provider for diagnosis and for answers to your personal questions.

What was this study's impact?

The similarity of results researchers found from the analysis of mixtures of PFAS chemicals and individual PFAS chemicals indicate that specific bioactive lipids could be useful biomarkers of PFAS exposure. Biomarkers are biological indicators of a particular health effect or status – in this case, PFAS exposure. They can be found in blood, urine, or other body fluids and can be substances, characteristics, genes, or proteins. This insight could help in understanding and addressing the health effects of PFAS by expanding screening methods.

The bioactive lipids measured in this study have not yet been tested as routine biomarkers in clinical settings. However, these findings aid in advancing the future of healthcare as additional and more complex lipid biomarkers become measurable and are tested for clinical use.

These findings encourage researchers to prioritize the study of PFAS and bioactive lipids pairs in future testing in addition to individually studying the effect of different types of PFAS. Additionally, this study highlights the importance of regulating the 12 types of PFAS observed.

Who was involved?

This study included 414 pregnant participants from three ECHO Cohort study sites: Chemicals in Our Bodies based in San Francisco, ECHO-PROTECT based in Puerto Rico, and Illinois Kids Development Study based in Chicago.

What happened during the study?

The research team estimated associations between prenatal PFAS exposure and bioactive lipids, measuring the levels of 12 types of PFAS and 50 bioactive lipids in 414 pregnant participants. Researchers quantified associations by using various statistical analyses while controlling for several factors (e.g., maternal age, gestational age at sample collection, maternal education, pre-pregnancy BMI).

What happens next?

The researchers plan to measure associations between bioactive lipids and peri- and prenatal mental health outcomes including perinatal and postpartum depression. Future studies could also look at the influence of other variables on this relationship. For example, researchers could investigate the influence of diet, which has been linked to changes in both PFAS and bioactive lipid concentrations.

Where can I learn more?

Access the full journal article, titled “Cross-Sectional Associations between Prenatal Per- and Poly-Fluoroalkyl Substances and Bioactive Lipids in Three Environmental Influences on Child Health Outcomes (ECHO) Cohorts,” in Environmental Science and Technology.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published May 14, 2024

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ECHO Cohort Study Finds Association Between PFAS and Bioactive Lipids

ECHO Study Finds Link Between Phthalate Exposure and Preterm Birth, Estimates Potential Costs

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ECHO Study Finds Link Between Phthalate Exposure and Preterm Birth, Estimates Potential Costs

Authors: Leonardo Trasande, et al.

Who sponsored this study?

The Environmental influences on Child Health Outcomes (ECHO) Program, Office of The Director, National Institutes of Health supported this research.

Why was this study needed?

Phthalates are widely used chemicals found in some consumer products, and previous research has linked phthalate exposure to preterm birth. In response, the use of di-2-ethylhexyl phthalate (DEHP), a common type of phthalate, has decreased in recent years. However, there is limited research on the effects of the replacement phthalates, and the costs associated with phthalate exposure remain unquantified. ECHO Cohort researchers wanted to learn about the potential connections between phthalates, their metabolites in the urine of pregnant individuals, and birth outcomes—including birth weight and length of pregnancy. The study also sought to estimate the potential costs associated with adverse birth outcomes.

What were the study results?

When the researchers grouped mothers based on the amount of DEHP metabolites (substances produced when the body breaks down DEHP) found in their urine, they found that the 10 percent with the highest levels had a 50 percent higher chance of giving birth before the 37th week of pregnancy compared to the 10 percent with the lowest levels.

Some common alternatives to DEHP were associated with even higher risk of preterm birth. Women exposed to the highest amounts of these alternative chemicals—phthalic acid, di-isodecyl phthalate (DIDP), di-n-octyl phthalate (DnOP), and diisononyl phthalate (DiNP)—had twice the risk of preterm birth compared to those with little to no exposure to these alternatives.

Researchers estimated that the number of premature births in the U.S. that could be linked to phthalate exposure in 2018 was between 24,000 and 120,000, potentially costing between $1.6 billion and $8.1 billion in medical expenses over the lifetime of the children.

Footnote: Results reported here are for a single study. Other or future studies may provide new information or different results. You should not make changes to your health without first consulting your healthcare professional.

What was this study's impact?

This ECHO Cohort research examines the effect of phthalates on birth outcomes such as preterm birth and birth weight. These findings associated adverse birth outcomes with exposure to DEHP and its chemically similar substitutes, which can inform the development of policies, programs, and practices that can help prevent or lessen potentially harmful exposures during pregnancy.

Who was involved?

The study included 5,006 mother-child pairs from 13 ECHO Cohort Study Sites across the U.S. Researchers included individuals with information on up to 20 urinary phthalate metabolites. The pregnant participants were aged 25 to 34 at the time they gave birth.

What happened during the study?

The researchers analyzed levels of 20 phthalate metabolites in urine samples collected at three points during each participant’s pregnancy. They also investigated the differences between specific types of phthalates, comparing DEHP with several newer alternatives developed to replace it. Then, the team looked for associations between these metabolite levels and preterm births. They also calculated the number of premature births that could be linked to phthalate exposure and the possible associated costs over the lifetime of the child.

What happens next?

Future research could look at how exposure to replacement phthalates affects child development after birth. The European Union has prohibited the use of certain phthalates in some consumer products—as have California and a few other U.S. states.

Where can I learn more?

Access the full journal article, titled “Prenatal phthalate exposure and adverse birth outcomes in the USA: a prospective analysis of births and estimates of attributable burden and costs,” in The Lancet Planetary Health.

The content is the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Published February, 2024

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ECHO Study Finds Link Between Phthalate Exposure and Preterm Birth, Estimates Potential Costs

Exposure to Common Flame-retardant Chemicals During Pregnancy May Be Associated with Behavioral Issues in Young Children, ECHO Study Finds

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Prenatal Exposure to Phthalates, But Not Phthalate Replacements, Linked to Children’s Behavior, ECHO Study Finds

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Young Children May Be Exposed to a Variety of Emerging Chemicals Found in Some Consumer Products

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ECHO Researchers Investigate Association of Early Childhood Phthalate Exposures with ADHD Behaviors in Childhood and Adolescence

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What was this study's impact?

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ECHO Cohort Study Finds Association Between PFAS and Bioactive Lipids

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ECHO Study Finds Link Between Phthalate Exposure and Preterm Birth, Estimates Potential Costs

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