A Raymond woman was in the midst of her pregnancy when her private well tested positive for arsenic at 43 parts per billion. New Hampshire’s maximum contaminant level for arsenic in drinking water is 5 parts per billion.

The woman received the alarming, but essential, information through the NH Water Well-Ness Initiative, a program that provides free private well testing for low-income pregnant participants of the Special Supplemental Nutrition Program for Women, Infants, and Children, commonly known as WIC. Because of her well’s test results, she was given free water filters and a pitcher.

When it comes to things that pose threats to an unborn child, most don’t suspect their drinking water at home. But for private well users across the state, that can be a reality. 

Nearly half of New Hampshire residents get their water from private wells, which aren’t regulated like public water systems. As a result, there are elevated risks of contaminants, and the responsibility falls on the homeowner. The Department of Environmental Services has estimated that 25 percent of private wells exceed the state’s 5 ppb maximum contaminant level for arsenic in drinking water.

For pregnant people, exposure to arsenic, a naturally occurring element, has been linked to a slew of adverse maternal-child health outcomes. While testing kits, filtration systems, or well treatment may be achievable for some, not everyone has the financial means or capability to probe the safety of their drinking water. 

A collaboration between the state’s departments of Health and Human Services and Environmental Services, the NH Water Well-Ness Initiative started in 2020, seeking to close a regulatory gap for arsenic in private wells, specifically for low-income pregnant people. That effort has since expanded to four other heavy metals considered toxic during pregnancy.

WIC is a federal program that provides nutritious foods, healthy eating education, and health care referrals to a population facing “nutritional risk.” Through the NH Water Well-Ness Initiative, eligible WIC participants collect a water sample to be sent to a state laboratory. If their water tests high for arsenic, manganese, lead, copper, or uranium, they’re mailed free ZeroWater filters and a pitcher. 

“The goal is to essentially reduce heavy metal exposure among a more vulnerable population, specifically pregnant women,” said Hannah Scott, nutrition coordinator for WIC within DHHS. “All of these heavy metals have been shown to have potential negative effects during pregnancy and for infants.”

The program has received attention from researchers. The Harvard T.H. Chan School of Public Health conducted a case study on results from the program’s pilot year in 2020 and 2021, which focused on Rockingham and Hillsborough counties. The study called it “a notable example of interagency collaboration between state agencies responsible for water quality and human health and nutrition assistance.”

The program, funded by the DES Drinking Water and Groundwater Bureau, expanded statewide in March 2022. According to Scott, between April 2022 and July 2023, 89 participants opted into the program, 39 returned their samples, and 13 had heavy metal exceedances for arsenic, uranium, and manganese.

“It’s been a great educational opportunity,” said Scott. “It’s not necessarily something that everyone is thinking about. It’s kind of an assumption that we have safe drinking water, which is not necessarily the case.”

When Scott was working at a local community action agency prior to joining DHHS, she said every time she spoke to a pregnant person about the program, “they were all enthusiastic and wanted to participate.”

“Everyone wants to have a healthy pregnancy and a healthy baby,” she said. 

Many WIC participants are also renters, meaning they likely can’t afford to implement more expensive water safety options or they might be moving more regularly. The NH Water Well-Ness Initiative enables them to test their water wherever they are and use water filters if results indicate a need. 

Caitlin Howe, an assistant professor of epidemiology at Dartmouth College, said pregnant people and children are “such vulnerable populations” in regard to toxic exposure. A Dartmouth study in 2016, for example, found that higher levels of arsenic in a mother’s urine during the second trimester was related to decreased head circumference at birth.

“Arsenic is a major concern,” said Howe, whose expertise is arsenic. “It’s a known carcinogen. There have been studies linking it to higher blood pressure, gestational diabetes, adverse birth outcomes, reduced lung functions.” 

A pregnant person, Howe said, is experiencing “dramatic physiological changes” that make them more susceptible to things like glucose intolerance, changes in blood pressure, and higher risk of depression and anxiety.

Meanwhile, a fetus or young child is rapidly growing and developing, oftentimes with immature defenses. A developing baby is going through “programming events,” Howe said, that if disrupted “can lead to long-lasting effects on health.”

She noted about 10 percent of Dartmouth’s New Hampshire Birth Cohort Study – which includes over 1,500 women and 1,500 children from both New Hampshire and Vermont who use private wells – have levels of arsenic exceeding 10 micrograms per liter, the federal standard that’s higher than New Hampshire’s state standard. 

Twenty-eight mother-child pairs from the New Hampshire Birth Cohort Study were recently analyzed as part of a National Institutes of Health study linking PFAS exposure to obesity risk. Despite increasing evidence that PFAS in drinking water can be attributed to adverse health outcomes, Scott noted the WIC water testing program does not currently include PFAS.