Pregnant women have been advised to use water filters by experts who spoke to Newsweek after a study found levels of arsenic in water systems considered safe are impacting birth outcomes,A national study led by researchers at Columbia University evaluated risks from 13,998 pregnancies across 35 cohort sites participating in the National Institutes of Health’s Environmental influences on Child Health Outcomes (ECHO) program, and published its findings on the medical journal site JAMA Network last week.The researchers discovered that prenatal exposure to arsenic was associated with a higher likelihood of babies being born preterm with lower birth weights, factors that they said are important “predictors of infant mortality and morbidity across the life span.”This was the case even at the level of exposure the Environmental Protection Agency (EPA) currently deems safe, 10 micrograms per liter, a regulation that was established in 2001 and has not been changed since.Impacts of Arsenic Exposure on Public HealthArsenic is a natural element found in soils, sediments, and groundwater, meaning it can feed into public drinking water systems.While this study highlights concerns of arsenic exposure in relation to pregnancy and birth outcomes in particular, the contaminant poses health risks to any individual.In the Centers for Disease Control and Prevention (CDC) toxicology report on arsenic, the agency notes, “it is widely accepted that arsenic is carcinogenic,” and that “numerous epidemiological studies have examined associations between
exposure to arsenic in drinking water and various health outcomes.””Arsenic can cause a variety of cancers, including cancer of the bladder and urothelium, gastrointestinal tract, kidney, liver, lung, pancreas, and skin; as well as cardiovascular effects, and neurologic effects,” Brett A. Poulin, a professor in the Department of Environmental Toxicology at the University of California, Davis, told Newsweek via email in response to the study.States also have different exposure levels, the study said, with Michigan, South Dakota, Nevada, and California all having areas with levels of higher than 5 micrograms per liter of arsenic in drinking water systems.”Arsenic levels tend to be higher in drinking water that comes from groundwater sources, such as community wells or private household wells,” Poulin said. “In many cases, the arsenic comes from natural minerals in the aquifer—especially in regions with sedimentary rocks or glacial deposits that contain arsenic-bearing materials.”He added that people living in areas that depend heavily on groundwater, and have geology rich in arsenic-containing sediments, are more likely to have elevated arsenic in their drinking water.Establishing a ‘Safe’ Contaminant Exposure LevelAsked whether the agency believes the level of arsenic exposure considered safe needed to be updated following the release of the study, an EPA spokesperson told Newsweek that determining a safe level of exposure requires a consideration of implementation and cost, as well as public health.”The Maximum Contaminant Level Goal (MCLG) established under the Safe Drinking Water Act (SDWA) is set at zero for arsenic,” the spokesperson said.The MCLG is identified in the act as the maximum level of a contaminant in drinking water at which “no known or anticipated adverse effect on the health of persons would occur, allowing an adequate margin of safety,” they added.However, MCLGs are “non-enforceable public health goals,” the spokesperson said. “MCLGs consider only public health, therefore, they sometimes are set at levels which water systems cannot meet due to technical limitations.”The spokesperson said the act requires the EPA to set the enforceable Maximum Contaminant Level (MCL) “as close as feasible to the MCLG taking cost into consideration.”Therefore, in its determination of a MCL of 10 micrograms per liter of arsenic exposure, the EPA had to evaluate the impact on costs and on public health, in a “health risk reduction and cost analysis.”The spokesperson added that the EPA regularly reviews National Primary Drinking Water Regulations and “evaluates whether there are new peer reviewed health assessments for a contaminant.”According to the spokesperson, in July 2024 under the Biden administration, the agency “completed the fourth cyclical review of drinking water regulations and determined that arsenic was not a candidate for revision at the time.””The Biden Administration noted that a regulatory revision for arsenic was not appropriate because the reassessment of the health risks resulting from exposure to arsenic was ongoing,” the EPA spokesperson said.Although, in light of the study, Poulin said: “One thing the EPA must consider when revising MCLs is feasibility of achieving a more stringent MCL.””There is no such thing as completely safe water, whether it is bottled or tap water,” Marc Edwards, a professor in civil and environmental engineering at Virginia Tech, told Newsweek.Although, he added this new research should be “considered in future revisions of the regulated arsenic level.”Pregnant Women Advised To Use Water FiltersGiven the impact of even accepted levels of arsenic exposure on pregnancy and birth, experts have advised expecting mothers at risk of higher exposure to use water filters.”In situations with high risk of lead or arsenic, filters are recommended,” Edwards said.”Waters with elevated arsenic are relatively rare compared to the problem of lead, and can be identified by reading your water companies consumer confidence report,” he added.”This research underscores our responsibility as a society to protect the health of pregnant women,” Marci Lobel, a professor in the Department of Obstetrics, Gynecology and Reproductive Medicine at Stony Brook University, New York, told Newsweek.”Clearly, we must reduce arsenic levels in public water supplies,” she said and advised pregnant women to filter their water if possible.Although, Lobel added that “pregnant women should not be unduly alarmed,” as despite the study’s findings, which are a “serious concern,” the impacts are “not large.””We should consider the results of this important study in the context of what we already know about reducing health risks for pregnant women,” she added.”It is well known that pregnancy is a highly vulnerable time for environmental exposures to have an impact on pregnant women and their babies,” Natalie Exum, a professor in the Department of Environmental Health and Engineering at Johns Hopkins Bloomberg School of Public Health, told Newsweek.She added that she was “concerned” about the findings of the study, and that they indicate that the “current regulation set in the Safe Drinking Water Act may not be protecting maternal and child health.””If you are pregnant and living in an area where there are detectable levels of arsenic in the drinking water, it would be best to use a filter that removes the arsenic to non-detectable levels,” she said.