America's Drinking Water is Changing How Babies Are Being Born: Study

Newsweek

a day ago

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Even low levels of arsenic in U.S. public drinking water may increase the risk of below average birth weight and other adverse birth outcomes, says a new national study led by researchers at Columbia University.
The findings, drawn from nearly 14,000 pregnancies across 35 cohort sites participating in the National Institutes of Health's Environmental influences on Child Health Outcomes (ECHO) program, were published on the medical journal site JAMA Network earlier this week.
"It is concerning, but what really stands out as major concern from this study is that no exposure level seems truly safe during pregnancy," Vasilis Vasiliou, chair and professor of environmental health sciences at Yale School of Public Health, told Newsweek.
Newsweek has contacted the EPA via email for comment.
Why It Matters
The research addresses growing concerns about the adequacy of U.S. drinking water safety standards, particularly for vulnerable populations. The findings suggest that health risks may occur from exposure below levels currently considered safe by the Environmental Protection Agency's (EPA) arsenic limit that was determined in 2001.
The study also said that low birth weight and preterm birth are "important predictors of infant mortality and morbidity across the life span," highlighting that low-level exposure to arsenic in drinking water could have prolonged and even fatal impacts.
File photo: a young girl drinks some water from a bottle.
File photo: a young girl drinks some water from a bottle.
Nicolas Messyasz/Sipa via AP
What To Know
The study found that prenatal exposure to arsenic—even below the current federal standard of 10 micrograms per liter—was linked to a higher likelihood of babies being born preterm, with lower birth weights, or smaller than expected for their gestational age.
Preterm birth was noted when a baby had a gestational age of less than 37 weeks, and low birth weight was identified as a weight of less than 2500 grams, or 2.5 kilograms.
Both outcomes were observed across multiple racial and ethnic groups, including White, Black, Hispanic/Latino, American Indian, Alaska Native, Native Hawaiian, and Pacific Islander families.
The authors noted that the risk of low birth weight following prenatal exposure to arsenic was higher among White, Black and Hispanic/Latino birthing parents.
"Arsenic's toxicity during pregnancy is multifactorial, involving oxidative stress, epigenetic disruption, placental toxicity, immune dysregulation, and hormonal interference—all of which can independently or jointly lead to low birth weight, preterm birth, and developmental programming of chronic disease," Vasiliou told Newsweek.
In 2001, the EPA announced its 10 micrograms per liter standard for arsenic. At the time, the EPA Administrator, Christine Todd Whitman, stated that "the 10 ppb protects public health based on the best available science and ensures that the cost of the standard is achievable."
However, some states, such as New Jersey and New Hampshire, have since enacted stricter limits of 5 micrograms per liter.
"Arsenic is released from rocks and soil into groundwater, which then feeds into municipal supplies," Vasiliou said.
He added that regions like the Southwest, parts of New England, Minnesota, and Wisconsin "are known for elevated natural levels."
Human activities like mining, agriculture, and industrial processes "can raise arsenic levels in nearby water systems," he said.
What People Are Saying
Vasilis Vasiliou, chair and professor of environmental health sciences at Yale School of Public Health, told Newsweek: "I believe that based on this, the EPA should consider lowering the maximum contaminant level below 10 µg/L. The authors explicitly recommend this as a way to help reduce low‑birth weight rates. More frequent testing of public water systems, especially in high‑risk locales, along with investment in treatment technologies, for example coagulation, adsorption, ion exchange, will be essential. Communities with elevated but sub-limit arsenic should be informed about risks, and pregnant people encouraged to use alternative water sources or filtration. I believe that we should continue monitoring birth outcomes in relationship to low-dose arsenic exposure and refine risk estimates across different demographics."
He added: "Arsenic isn't the only chemical of concern in tap water; I can list PFAS, 2,4-dioxane and other emerging chemical contaminants. Therefore, pregnant people often face multiple low-level exposures. Even small reductions in one contaminant can yield meaningful health improvements when cumulative."
What Happens Next
The study's authors urged for further research to dissect the combined influence of arsenic and other social determinants of health. They also stressed the importance of reviewing legacy contaminants like arsenic and updating health-based water safety standards at both federal and state levels.