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

ECHO Study Finds Exposure to Phenols During Pregnancy Associated with Changes in Non-Nutritive Suck Patterns in Infants

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ECHO Study Finds Exposure to Phenols During Pregnancy Associated with Changes in Non-Nutritive Suck Patterns in Infants

Authors: Megan Woodbury, Andréa Aguiar, Emily Zimmerman, 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?

During this study, researchers evaluated the relationship between exposure to phenols—chemicals used in a variety of consumer products and industrial processes that can disrupt hormones—during pregnancy and non-nutritive sucking patterns in infants. Non-nutritive sucking is a common behavior during infancy where a baby may suck on an object that cannot provide nutrients, such as a pacifier. Non-nutritive sucking is characterized by bursts of sucking separated by pauses to breathe. Researchers can measure the frequency, speed, and strength of non-nutritive sucking. Because sucking is a behavior present from birth that is controlled by neurons in the brainstem, it is an ideal indicator of early brain development. Previous studies have indicated that non-nutritive sucking patterns can be affected by environmental exposures during pregnancy. Understanding this relationship could provide insights into how prenatal chemical exposures impact early neurodevelopment.

What were the study results?

The study found that phenol exposure during pregnancy was linked to changes in non-nutritive suck patterns in infants. Specifically, exposure to Bisphenol F, a common alternative to Bisephenol A or BPA found in some food packaging, was related to a lower non-nutritive suck frequency. Alternatively, exposure to Triclosan, an antimicrobial chemical found in some soaps, was associated with a higher non-nutritive suck frequency. Exposure to other phenols used as preservatives and industrial processes (propylparaben, 2,4-dichlorophenol, and 2,5-dichlorophenol) was associated with weaker non-nutritive suck. Exposure to some phenols used in sunscreens and industrial processes (benzophenone-3, 2,4-dichlorophenol, and 2,5-dichlorophenol) were related to more non-nutritive suck bursts per minute. Propylparaben, a chemical used in some preservatives, was associated with more non-nutritive sucking per burst.

What was this study's impact?

This study provides additional evidence that exposure to phenols may affect early brain development. Continued research into the effects of pregnancy exposures on infant health and development can help inform strategies for reducing potentially harmful exposures.

Who was involved?

The study included 215 mother-infant pairs from two ECHO Cohort study sites: the Illinois Kids Development Study (IKIDS) and ECHO in Puerto Rico (ECHO-PROTECT).

What happened during the study?

During the study, researchers measured phenol exposure by analyzing phenol levels in maternal urine samples collected during pregnancy. Non-nutritive sucking was evaluated in 1- to 8-week-old infants using a custom pacifier for approximately 5 minutes. Statistical methods were used to investigate how exposure to 11 different phenols and triclocarban—another chemical used as an antibacterial agent in some soaps—affected non-nutritive suck, adjusting for factors like study site, child sex and assessment age, and maternal age and education.

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 clarify why non-nutritive suck patterns change in response to certain pregnancy exposures and how these changes might affect the baby's brain development as they grow.

Where can I learn more?

Access the full journal article, titled “Examining the association between prenatal Phenol exposure and infant non-nutritive suck in two ECHO Cohorts,” in Environmental Epidemiology.

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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ECHO Study Finds Exposure to Phenols During Pregnancy Associated with Changes in Non-Nutritive Suck Patterns in Infants

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 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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Adverse Birth Outcomes May be Associated with Arsenic Levels in Public Drinking Water

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Adverse Birth Outcomes May be Associated with Arsenic Levels in Public Drinking Water

Authors: Anne Nigra, 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?

Regulated U.S. public drinking water is a source of exposure to arsenic. Because arsenic occurs naturally, water that comes in contact with certain rocks and soils may contain it. Contamination from various industrial processes also contributes to increased levels of arsenic in some areas. Prenatal exposure to arsenic has been associated with adverse birth outcomes, including preterm birth and low birthweight. Researchers studied how arsenic in public drinking water—at levels below the federal limit—may affect birth outcomes in the ECHO Cohort. Previous evidence has been limited to private well exposures, studies using urinary biomarkers, and single-site studies with limited racial, ethnic, and geographic diversity.

What were the study results?

The study found that when pregnant women lived in areas with publicly reported high levels of arsenic in public drinking water, even at levels below the current federal safety standard of 10 micrograms per liter, their babies were more likely to be born with low birthweight (weighing less than 5 lbs 8 oz) or are small for their gestational age (smaller than babies born at the same number of weeks of pregnancy). These patterns were seen across several racial and ethnic groups, including White, Black, and Hispanic/Latino families. For example, babies born to Hispanic/Latino parents were about 40% more likely to have low birthweight with just a 5 microgram-per-liter increase in water arsenic. The study also found that babies born to Black parents had higher risks of being born early, with low birthweight, or smaller for their gestational age. Similar risks were observed among babies born to American Indian, Alaskan Native, Native Hawaiian, and Pacific Islander parents.

What was this study's impact?

The study shows that even low levels of arsenic in public drinking water may increase the risk of babies being born too early, too small, or underweight.

Who was involved?

Participants included 13,998 birthing mother-infant pairs from the ECHO Cohort.

What happened during the study?

Researchers estimated how much arsenic people were exposed to through public drinking water during pregnancy by combining water quality data with where each person lived each month. They then looked at whether that exposure was linked to outcomes like being born early (preterm birth), having a low birthweight, or being small for their gestational age.

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 research could help researchers understand how current efforts to reduce arsenic in drinking water are working—whether those efforts happen across the country, in local communities, in homes, or for individuals. Studies could also help identify where arsenic levels are highest, which may support ongoing work to make sure communities have safe drinking water.

Where can I learn more?

Access the full journal article, titled “Public water arsenic and birth outcomes in the Environmental influences on Child Health Outcomes Cohort,” in JAMA Network Open.

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

Published June 16, 2025

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Adverse Birth Outcomes May be Associated with Arsenic Levels in Public Drinking Water

Prenatal Exposure to Air Pollution Associated with Higher Risk for Autism-related Outcomes, ECHO Study Finds

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Prenatal Exposure to Air Pollution Associated with Higher Risk for Autism-related Outcomes, ECHO Study Finds

Author(s): Heather Volk, Akhgar Ghassabian, 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?

Air pollution is a significant environmental health concern and contributes to many illnesses and early deaths worldwide. Ambient air pollution can have detectable effects on the brain. Recent studies show that being exposed to air pollution during pregnancy and early life can affect how a child’s brain develops. This can happen through several pathways, such as causing inflammation in the brain, disrupting hormones, or changing how genes work. Previous research has suggested potential links between air pollution and neurodevelopmental disorders, but the relationship between exposure to air pollution, even at low levels, during pregnancy and ASD has been unclear. This study examined the associations between prenatal air pollution exposure and autism spectrum disorder (ASD) in children.

What were the study results?

The study team observed that higher prenatal exposure to ozone was associated with autism-related traits and increased risk of ASD diagnosis. Exposure to fine particulate matter (PM_2.5) and nitrogen dioxide was also associated with a higher risk of autism, but associations varied by geographical regions. There was little evidence for differences between boys and girls in the association between prenatal air pollution exposure and autism outcomes.

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 the study's impact?

The study's findings suggest that even low levels of air pollution exposure during pregnancy might be associated with autism-related outcomes. This highlights the importance of understanding the risks associated with air pollution exposure during pregnancy and its effects on child neurodevelopment.

Who was involved?

The study involved 8,035 mother-child pairs from 44 ECHO study sites across the United States. This sample included over 1,000 child participants who were potentially at higher risk for ASD due to being born preterm or having siblings with autism. The remaining participants were recruited from samples representative of the general population.

What happened during the study?

This study looked at scores from the Social Responsiveness Scale (SRS), a parent-report tool that measures autism-related traits in children, with higher scores indicating higher autism-related traits. During the study, researchers estimated daily exposure to particulate matter, nitrogen dioxide, and ozone at the residential addresses of pregnant women. They then analyzed the associations between these air pollutants and autism-related traits using the Social Responsiveness Scale (SRS) and physician-diagnosed ASD.

What happens next?

The study results suggest that even small changes in prenatal air pollution exposure could have a significant impact on child neurodevelopment. Future studies are needed to understand why these connections exist and to look at the impact of specific air pollution components.

Where can I learn more?

Access the full journal article, titled “Prenatal Air Pollution Exposure and Autism Spectrum Disorder in the ECHO Consortium,” in Environmental Health Perspectives.

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

Published June 11, 2025

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Prenatal Exposure to Air Pollution Associated with Higher Risk for Autism-related Outcomes, ECHO Study Finds

Prenatal Exposure to Organophosphate Esters Associated with Increased Autism-Related Outcomes, ECHO Study Finds

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Prenatal Exposure to Organophosphate Esters Associated with Increased Autism-Related Outcomes, ECHO Study Finds

Author(s): Jennifer Ames, 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 (OPE) replaced harmful polybrominated diphenyl ethers (PBDEs) as flame retardants and plastic softeners in the mid-2000s. They are now present in various household and industrial products, including polyurethane foam, furniture, electronics, construction materials, infant products, textiles, and fabrics. Health officials and researchers currently know little about how OPEs affect child development. Earlier studies have suggested a link between prenatal exposure to these chemicals and birth outcomes and cognitive and behavioral problems in children. This study investigated the potential effects of prenatal exposure to nine OPEs on child autism-related outcomes.

What were the study results?

The study found generally small associations between three OPEs and child autism-related outcomes. Specifically, high exposure to bis(butoxyethyl) phosphate (BBOEP) was associated with higher scores for autism-related traits and greater odds of autism diagnosis. Another OPE, bis(1-chloro-2-propyl) phosphate (BCPP) showed associations with higher autism-related trait scores. High exposure to bis(2-chloroethyl) phosphate (BCETP) was associated with lower odds of autism diagnosis. The study also found that the association between BBOEP and higher autism-related traits scores was stronger in boys than in girls.

What was the study's impact?

This study underscores the need to better understand and address the potential developmental toxicity of these widely used chemicals.

Who was involved?

The study included 4,159 mother-child pairs with children born from 2006 to 2020 from 15 study sites in the ECHO Cohort.

What happened during the study?

Researchers analyzed urine samples from pregnant mothers for nine OPE biomarkers. The researchers then assessed child autism-related traits via the Social Responsiveness Scale (SRS) and collected information on whether they received a clinical autism diagnosis to examine associations between prenatal OPE exposure and child neurodevelopment.

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 research could replicate these findings in different populations and use multiple measures of OPEs throughout pregnancy to better understand the critical exposure windows and long-term effects of OPEs on child neurodevelopment. Additionally, further studies could help researchers explore the potential sex-specific effects of prenatal OPE exposure.

Where can I learn more?

Access the full journal article, titled “Exposure to organophosphate ester flame retardants and plasticizers during pregnancy and autism-related outcomes in the ECHO Cohort,” in Environmental Health Perspectives.

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

Published June 11, 2025

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Prenatal Exposure to Organophosphate Esters Associated with Increased Autism-Related Outcomes, ECHO Study Finds

Prenatal Exposure to Phenols and Parabens Higher Among Minority Populations, ECHO Study Finds

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Prenatal Exposure to Phenols and Parabens Higher Among Minority Populations, ECHO Study Finds

Authors: Michael S. Bloom, Adaeze Wosu Nzegwu, et al.

Who sponsored this study?

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

Why was this study needed?

Exposure to endocrine-disrupting chemicals (EDCs), such as environmental phenols (EPs) and parabens, is common during pregnancy through everyday products like plastics, food packaging, and personal care items. These chemicals can cross the placenta and, despite their short breakdown time in the body, EPs are often detected in human tissue. Prenatal exposure has been linked to risks such as pregnancy complications, developmental issues, and long-term health problems, particularly in underserved populations. Low-income and minority communities may face higher exposure to chemicals like EPs due to closer proximity to factories and waste facilities, as well as limited access to a broader range of consumer products and fresh foods. This study investigated racial and ethnic differences in prenatal exposure to EPs and parabens across the U.S., addressing the limitations of earlier, smaller studies that did not fully explore these differences among pregnant women.

What were the study results?

Urinary levels of most EPs examined varied significantly by race and ethnicity, with non-Hispanic Black and Hispanic participants having higher levels of certain EPs than non-Hispanic White participants. Specifically, non-Hispanic Black and Hispanic participants had higher average levels of a chemical that comes from paradichlorobenzene in their urine compared to non-Hispanic White participants. Paradichlorobenzene is found in mothballs, fumigants, and air fresheners, and it is mainly inhaled. Non-Hispanic Black participants also had higher levels of specific parabens, which are preservatives used in processed foods and personal care products. These chemicals can be absorbed through eating or using such products.

What was this study's impact?

The study highlighted the disproportionately high levels of exposure to EPs among pregnant racial and ethnic minorities in the U.S.

Who was involved?

The study included 4,006 pregnant participants from 11 ECHO Cohort Study Sites across the U.S., representing various racial/ethnic identities, including Hispanic, non-Hispanic Black, non-Hispanic Other, and non-Hispanic White individuals.

What happened during the study?

The study analyzed 7,854 urine specimens collected during pregnancy. Researchers measured the levels of 10 different urinary EPs.

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?

Further studies could examine the sources of these exposure differences.

Where can I learn more?

Access the full journal article, titled “Racial and ethnic differences in prenatal exposure to environmental phenols and parabens in the ECHO Cohort,” in the Journal of Exposure Science and Environmental Epidemiology.

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

Published February 15, 2025

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Prenatal Exposure to Phenols and Parabens Higher Among Minority Populations, ECHO Study Finds

COVID-19 Pandemic May Have Altered Exposures to Environmental Chemicals, ECHO Study Finds

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COVID-19 Pandemic May Have Altered Exposures to Environmental Chemicals, ECHO Study Finds

Authors: Megan Romano, et al.

Who sponsored this study?

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

Why was this study needed?

The COVID-19 pandemic caused unprecedented disruptions in the daily lives of children and families worldwide. In the United States, recommendations to stay home and wear masks may have altered people's exposure to various potential endocrine-disrupting chemicals (EDCs). For example, changes in the use of certain consumer products, such as N-95 masks, and decreased exposure to air pollutants due to lockdown may have influenced these exposures. ECHO researchers wanted to learn whether exposures during pregnancy changed during the COVID-19 pandemic.

What were the study results?

During the COVID-19 pandemic, urinary levels of certain chemicals changed, reflecting shifts in exposure. Levels of specific polycyclic aromatic hydrocarbons (PAHs), which are air pollutants from car exhaust, fire smoke, and some grilled foods, decreased. Some synthetic phenols, used in plastics and disinfectants found in household cleaners and consumer products like mouthwashes, also showed a decline. However, levels increased of certain organophosphate esters (OPEs)—chemicals used in plastics, flame retardants, and cleaning agents, and more recently in surgical, KN95, and N95 masks. - The increase in these chemicals may be linked to the use of face masks during the pandemic. When people wore masks regularly, they may have unknowingly inhaled small amounts of these chemicals, leading to higher levels in their bodies. In contrast, urinary concentrations of chemicals commonly found in plastics, personal care products, and pesticides remained largely unchanged.

What was this study's impact?

The study highlighted how significant behavioral changes during the pandemic may have contributed to changes in exposures to harmful environmental chemicals.

Who was involved?

The study included 47 participants from three ECHO Cohort Study Sites who contributed urine samples before and during the COVID-19 pandemic.

What happened during the study?

Researchers collected urine samples from participants before (between October 2018 and February 2020) and during (between March 2020 and April 2021) the COVID-19 pandemic. They tested the samples for various chemicals.

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?

Researchers could continue tracking changes in chemical exposures and their potential health effects to better understand how these environmental exposures change over time, particularly during significant societal changes like the COVID-19 pandemic.

Where can I learn more?

Access the full journal article, titled “Changes in urinary concentrations of contemporary and emerging chemicals in commerce during the COVID-19 pandemic: Insights from the Environmental influences on Child Health Outcomes (ECHO) program,” in PLoS One.

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

Published January 24, 2025

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COVID-19 Pandemic May Have Altered Exposures to Environmental Chemicals, ECHO Study Finds

ECHO Study Investigates Exposure to Flame-Retardants During Pregnancy and Childhood Obesity Risk

Authors: Alicia K. Peterson, Assiamira Ferrara, 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 (OPE) replaced polybrominated diphenyl ethers (PBDEs) as flame retardants and plastic softeners in the mid-2000s. They are now present in various household and industrial products, including polyurethane foam, furniture, electronics, construction materials, infant products, textiles, and fabrics. Health officials have raised concerns about their impact on hormone systems and potential links to obesity. This study looked at whether the levels of OPEs found in a mother's urine during pregnancy were associated with a higher risk of obesity in her child.

What were the study results?

The study found varying associations between gestational OPE exposure and childhood obesity. The study found that children aged 5 to 10 years who were exposed to higher levels of dibutyl phosphate and di-isobutyl phosphate (DBUP/DIBP) during their mother’s pregnancy had a 14% greater risk of developing obesity compared to those with the lowest exposure levels. In contrast, children whose mothers had higher exposure levels of bis (1,3-dichloro-2-propyl) phosphate (BDCPP) during their mother’s pregnancy had a 15% lower risk of developing obesity than those with the lowest levels of exposure. Researchers measured for evidence of nine different OPEs in pregnant participants’ urine. Evidence of exposure to DBUP/DIBP and BDCPP was present in more than 80% of the samples. No association with obesity risk was observed for the rest of the OPEs measured.

What was this study's impact?

The study highlights the potential public health issue of gestational OPE exposure and its association with childhood obesity. It suggests the need for further investigation across a broad range of OPE exposures and could inform potential regulations on the manufacture and use of OPEs.

Who was involved?

The study involved 5,087 individuals from 14 ECHO Cohort Study Sites. The study population was geographically, racially, and ethnically diverse.

What happened during the study?

Researchers measured OPE exposure in the urine samples of pregnant participants between 2006 and 2020 and collected BMI measurements for the children from infancy to age 10 years.

Note: 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?

Further studies could help researchers better understand the associations between gestational exposure across a broad range of OPE exposures and childhood obesity.

Where can I learn more?

Access the full journal article, “Gestational Exposure to Organophosphate Ester Flame Retardants and Risk of Childhood Obesity in the Environmental influences on Child Health Outcomes Consortium,” 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 October 17, 2024

Read the associated press release.

Download this summary

ECHO Study Investigates Exposure to Flame-Retardants During Pregnancy and Childhood Obesity Risk