New ECHO Research Finds No Association Between Arsenic Exposure and Birth Outcomes

Posted on December 15, 2023June 5, 2024 by Jodi Snare

Collaborative ECHO research led by Jonathan Lewis, MHS, Emily Knapp, PhD, MHS, and Amii Kress, PhD, MPH of Johns Hopkins Bloomberg School of Public Health investigates the relationship between arsenic exposure and certain birth outcomes. This research, titled “Associations Between Area-Level Arsenic Exposure and Adverse Birth Outcomes: An ECHO-Wide Cohort Analysis,” is published in Environmental Research.

Researchers captured proxy exposure to arsenic using a residential history of arsenic violations from the preconception period throughout pregnancy, a time when environmental influences could disrupt fetal growth. Violations were used as a proxy for arsenic exposure. The study used data from 15,000 mother-child pairs at 51 research sites across the U.S., focusing on children born in 2006 or later. In 2006, the Environmental Protection Agency (EPA) revised the enforceable standard for arsenic concentrations in drinking water to 10 parts per billion.

Low birth weight, gestational age at birth, preterm birth, and birth size were not found to be associated with potential arsenic exposure in areas with violations. However, infants whose mothers experienced continuous exposure to arsenic from three months before conception through birth exhibited a statistically significant increase in birth weight compared to those born in areas without violations.

In future studies, researchers aim to improve the identification of the community water systems that serve ECHO participants. Future research could also consider ECHO participants’ exposure to arsenic in foods and from other sources of drinking water.

Read the research summary.

ECHO Study Finds No Association Between Arsenic Exposure and Birth Outcomes

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ECHO Study Finds No Association Between Arsenic Exposure and Birth Outcomes

Authors: Jonathan Lewis, Emily A. Knapp, Amii M. Kress, 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?

Arsenic is a naturally occurring, toxic chemical that can be present in groundwater and surface water. Drinking water, as a result, is one of the most common ways people are exposed to arsenic in the U.S. and globally. There have been a limited number of small studies of the association between arsenic and birth outcomes, mostly outside of the U.S. In this study, ECHO researchers examined a diverse group of pregnant participants from across the country to determine if birth outcomes—birth weight, gestational age at birth, preterm birth, and size at birth—are influenced by arsenic concentrations that are above regulatory action levels.

What were the study results?

Researchers found that low birth weight, gestational age at birth, preterm birth, and birth size were not associated with potential exposure to arsenic among pregnant women living in a county with active arsenic level violations. There was a statistically significant increase in birth weight among infants whose mother’s experienced continuous exposure (from three months before conception through birth) compared with infants from areas without violations.

Footnote: Results reported here are for a single study. 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?

Overall, drinking water violations for arsenic that could indicate the presence of the chemical above regulatory action levels are relatively uncommon. Researchers captured proxy exposure using residential history arsenic violations from the preconception period throughout pregnancy, a time when environmental influences could disrupt fetal growth.

Who was involved?

The study included over 15,000 mother-child pairs at 51 ECHO Cohort Study Sites across the United States. The children were born in 2006 or later, as the U.S. Environmental Protection Agency (EPA) changed the enforceable standard for arsenic concentrations in drinking water to 10 parts per billion during that year. Only 794 participants experienced arsenic violations.

What happened during the study?

Researchers grouped pregnant participants based on where they lived three months before conception and during pregnancy. Within those areas, investigators determined which public water systems had violations for arsenic. Then they looked at how living in a county with an arsenic violation might affect birth outcomes.

What happens next?

Future research could better identify ECHO participants’ exposure to arsenic by considering other sources of drinking water (e.g., bottled or filtered water) and exposure to arsenic in foods.

Where can I learn more?

Access the full journal article, titled “Associations Between Area-Level Arsenic Exposure and Adverse Birth Outcomes: An ECHO-Wide Cohort Analysis,” in Environmental Research.

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

Published November 1, 2023

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ECHO Study Finds No Association Between Arsenic Exposure and Birth Outcomes

NIH Study Finds Association Between Elevated Phthalate Levels and Increased Risk of Postpartum Depression

Posted on September 21, 2023August 27, 2025 by Jodi Snare

FOR IMMEDIATE RELEASE

In a new study from the NIH’s Environmental influences on Child Health Outcomes (ECHO) Program, higher prenatal phthalate levels were associated with a slightly increased risk of postpartum depression.

Postpartum depression affects up to 20% of new mothers, making it the most common pregnancy complication to occur after delivery. ECHO Cohort researchers wanted to examine how chemicals such as phenols, phthalates, and parabens—commonly found in plastics and personal care products—might play a role in postpartum depression symptoms, alongside other factors like genetics and stress. Exposure to these chemicals can affect hormone levels, potentially influencing the development of postpartum depression.

The presence of these man-made chemicals in people is common due to frequent exposure through diet, absorption through the skin, and inhalation. Researchers noted that among study participants all had parabens and nearly all had phthalates in their urine samples.

“Finding new ways to prevent postpartum depression is crucial because most of the known risk factors, like genetics and stressful life events, can’t be altered,” said Melanie Jacobson, PhD, MPH of New York University’s Grossman School of Medicine. “Therefore, focusing on prenatal exposure to these types of chemicals represents a novel interventional target.”

Researchers measured the concentrations of these chemicals in urine samples of 2,174 pregnant individuals at five ECHO Cohort Study Sites. Those same individuals also completed depression assessments between two weeks and 12 months after delivery to check for postpartum depression symptoms. Screening instruments indicated the presence or absence of postnatal depressive symptoms. Researchers then harmonized data to the Patient-Reported Measurement Information System (PROMIS) Depression scale.

The study found that higher levels of phthalates, in particular those found in products such as personal care items and plastic consumer products, were associated with an increased risk of postpartum depression. Those who met the criteria for postpartum depression were more likely to be Hispanic and from the ECHO study site in Puerto Rico, have attained less education, and substantially higher prenatal depression scores.

This collaborative research, which is believed to be the largest study to date examining the effects of environmental chemicals on depression, is published in JAMA Psychiatry.

Jacobson, M. et al. Prenatal exposure to nonpersistent environmental chemicals and postpartum depression. JAMA Psychiatry. DOI: 10.1001/jamapsychiatry.2023.3542.

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New ECHO Research Finds Association Between Some Prenatal Chemical Exposures and Postpartum Depression

Posted on September 21, 2023September 21, 2023 by Jodi Snare

Collaborative ECHO research led by Melanie Jacobson, PhD, MPH of the NYU Grossman School of Medicine, investigates the role of prenatal synthetic chemicals in postpartum depression. This research, titled “Prenatal Exposure to Nonpersistent Environmental Chemicals and Postpartum Depression,” is published in JAMA Psychiatry.

Postpartum depression affects up to 20% of new mothers, making it the most common pregnancy complication to occur after delivery. Postpartum depression can impact a mother’s daily functioning, quality of life, and long-term health. Furthermore, it is associated with poor mother-child attachment, which can impact child health and development.

Factors like genetics and stress can make some people more likely to experience postpartum depression, but researchers are still trying to understand how synthetic chemicals might also play a role. Chemicals such as phenols, phthalates, and parabens can be found in plastics and personal care products. While these chemicals are nonpersistent, meaning that they don’t linger in the environment, their presence is widespread due to frequent exposure through diet, absorption through skin, and inhalation.

Researchers used data from 2,174 pregnant individuals across five study sites to examine the extent to which exposure to these chemicals might be associated with postpartum depression symptoms. They measured the concentrations of nonpersistent chemicals in urine samples during pregnancy and collected data using self-reported postnatal depression assessments after delivery completed by the same individuals.

The study found that prenatal phthalate concentrations were associated with increased odds of slightly higher postpartum depression scores. Of the many synthetic chemicals investigated, only phthalate concentrations were associated with increased odds of postpartum depression. This suggests that finding ways to reduce prenatal exposure to phthalates might reduce the frequency of postpartum depression. Researchers also observed that postpartum depression was more likely in people who were Hispanic, had lower educational attainment, and had prenatal depression.

“From a public health perspective, any way to help prevent postpartum depression would be important, since most known risk factors such as genetics, psychiatric history, and stressful life events, cannot be easily changed,” Dr. Jacobson said. “Therefore, focusing on prenatal exposure to these types of chemicals represents a novel interventional target.”

While this is believed to be the largest study to date examining the effects of environmental chemicals on postpartum depression, future studies are needed to replicate this research with larger sample sizes in diverse populations.

Read the research summary.

ECHO Cohort Researchers Find Association Between Some Prenatal Chemical Exposures and Postpartum Depression

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