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Member Research & Reports

Member Research & Reports

UNC Study: Extending Municipal Water Service May Reduce GI Illness in Those Who Rely on Private Wells

A study co-authored by a researcher at the University of North Carolina Gillings School of Global Public Health provides new evidence that extending regulated community water service to populations currently relying on private wells may decrease the population burden of acute gastrointestinal illness.


[Photo: Dr. Jackie MacDonald Gibson]

Dr. Jacqueline MacDonald Gibson, associate professor of environmental sciences and engineering at UNC, is a co-author of “Reducing Emergency Department Visits for Acute Gastrointestinal Illnesses in North Carolina by Extending Community Water Service,” published online May 20 in the journal Environmental Health Perspectives.

Previous research has shown that unregulated drinking water wells are more likely than regulated community water systems to be contaminated with microbes. Dr. MacDonald Gibson and colleagues wanted to determine gastrointestinal health risks that may face the 35 percent of North Carolina’s population dependent upon private wells.

Using 2007-2013 data from all 122 North Carolina emergency departments, along with official data from community water systems and 16,138 water samples from private wells, the researchers found that 29,400 visits to emergency departments for treatment of acute gastrointestinal illness (AGI) – 7.3 percent of all emergency visits for AGI – are associated with microbial contamination of drinking water.

Ninety-nine percent of these cases were associated with contamination of private wells.

The physical and financial burden of contaminated drinking water is significant. The study found that the annual cost of emergency department visits related to microbial contamination is $40.2 million, $39.9 million of which is attributable to microbes in private wells. The authors suggest that extending community water service to 10 percent of the population currently using private wells could prevent some 2,920 annual emergency department visits for AGI.

“This study shows how combining routinely collected data from different state agencies can shed light on important public health questions,” said Dr. MacDonald Gibson. “Not only is the this the first study to provide evidence of long-held concern about the health impacts of microbial contamination in private wells, but it also is the first to unite hospital emergency department visit data collected by the N.C. Department of Health and Human Services with drinking water quality data collected by county health departments and the N.C. Department of Environmental Quality to answer an important public health question. The results underscore the need for interventions to help private well owners protect the quality of their water or obtain water from cleaner sources.”

Other co-authors of the study are Dr. Nicolas B. DeFelice, UNC alumnus and now postdoctoral research scientist in environmental health sciences at Columbia University Mailman School of Public Health, and Dr. Jill Johnston, a UNC alumna and former postdoctoral fellow, now assistant professor of preventive medicine at the University of Southern California MPH Program.

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