What’s in your poop can say a lot about your neck of the woods.
Researchers from Duke University and UNC-Chapel Hill published a study last month on dietary DNA extracted from municipal wastewater across North Carolina communities. From sewage samples, the scientists found they could infer characteristics like economic status, foreign-born population size, seasonal shifts, and coastal proximity by analyzing the genetic material left from what people ate, digested, and flushed.
Now, they want to narrow their scope to the neighborhood level—in Durham.
The team of researchers are part of Edible Atlas, a lab based at Duke and led by associate professor Lawrence David. The lab studies the human diet “not just as a health input, but as a window into culture, economics, and how communities live,” per its website.
“We’re not interested in just telling you how you should eat differently and how you should improve your health,” Edible Atlas senior research analyst Michelle Kirtley told the INDY. “But we’re also interested in giving communities access to their dietary signals in order to give them unique things about their communities to celebrate, whether that’s cultural, seasonal, religious, whatever it might be.”
Studying residents’ health through wastewater isn’t unheard of; during the COVID-19 pandemic, wastewater sampling was commonly used to detect disease spread trends and has also been used in public health research to measure drug use, antibiotic resistance, and hormonal shifts. And researchers and agencies routinely sample wastewater in Durham, Joe Lunne, public information officer for the Department of Water Management, wrote to the INDY. Maintenance staff can pull and refrigerate samples from wastewater plants or might open up a manhole cover to let researchers take their own directly from the sewer main.
But the Edible Atlas scientists developed FoodSeq-FLOW (Food Landscape Observation in Wastewater), a DNA sequencing platform that uniquely “transforms municipal wastewater into a real-time window on population nutrition,” per a recent study conducted by Edible Atlas. FoodSeq-FLOW can survey genetic material from the plants and animals that people eat by analyzing what survives digestion.
The study, titled “Dietary DNA in Municipal Wastewater Reveals Signatures of Wealth, Immigration, and Coastal Proximity,” surveyed 21 North Carolina communities, including Durham and Raleigh, representing about 2.1 billion people (roughly a fifth of the state’s population) through 183 municipal wastewater samples. The study was the focus of a story in The New York Times on the nutrition field’s growing preference for the accessibility and inexpensiveness of wastewater analysis—as opposed to flawed self-reported questionnaires or expensive simulations.
David and his team concluded they could infer socioeconomic characteristics, and potentially food access needs, of regional populations from the dietary DNA that remains in sewage—after it’s flushed, before it’s treated. They found that hops, a key beer ingredient, was more likely to appear in samples from wealthier areas, tropical fruits and beans showed up in regions with high foreign-born populations, and local seafood was prevalent in coastal areas.
From June to December 2020, the Edible Atlas team sampled four wastewater treatment plants in the Charlotte-Mecklenburg area, three in Beaufort-Carteret, and one in Greenville-Pitt. Then, they sampled them again in June 2021. This set was to determine whether their testing method could detect changes over time, including seasonal shifts, and it did; one simple indicator was an uptick in turkey DNA in November and December.
In June 2021, researchers collected one-time samples from 19 wastewater treatment plants in Durham, Raleigh, Charlotte, Winston-Salem, Asheville, Wilmington, Greensboro, Fayetteville, Roanoke Rapids, Wilson, Newport, Marion, Laurinburg, and New Hanover. Researchers also specifically gathered 14 individual, untouched stool samples from Durham residents (also in June 2021) to check if their assessment of food DNA in sewage actually tracks with what people are eating—and it did.
But what will the scientists ultimately do with the poo?
The Edible Atlas team’s first study on North Carolina gathered data from municipal wastewater treatment centers that could represent thousands of people’s waste. Now, the team wants to narrow its focus to different neighborhoods in Durham, hoping it can be used to inform policy and spur food accessibility initiatives. The lab is partnering with community members to learn about what this sort of data can do for them. The hope is that tracking regional nutrition trends will arm food deserts and other resource-deprived areas with the data they need to advocate for improved access to nutritious food.
“The differences that we saw at the wastewater treatment plant level made us wonder: Are there differences that we could also see at the neighborhood level that we might be able to relate to something like food access and health, and start unpacking a little bit about why populations have different access to food and what we could do to help solve that?” Kirtley said.
But Edible Atlas also understands the concerns that come with surveilling vulnerable populations. They’re hosting an event on August 15 at the Durham County Library, where they’ll explain their Durham-focused project, answer resident questions, and take feedback from community members about what should be done with the data. The team never samples areas with less than 500 people, to preserve anonymity, Kirtley said.
Erin and Kendall Dooley, founders of the Durham nonprofit BLK South, are confident the research can be used for advocacy, particularly to secure a grocery store for Grant Street, one of the areas that is being studied. When they first saw David present about Edible Atlas at a community event, Erin Dooley said a “light bulb” went off in her head, and the collaboration began.
“That partnership has just looked like a relationship, trust, communication, and working together to use the data that has been collected to help get in front of a larger audience—and maybe get this thing done,” she said.
BLK South is partnered with the Grant Street Community, part of Durham’s 100-year old historically Black Hayti neighborhood, which was decimated when 1960s urban renewal and the construction of the Durham Freeway displaced 4,000 families and 500 businesses. BLK South is advancing the neighborhood’s 15-year vision, which calls for a full-service grocery store.
There’s an estimated $6 million funding gap preventing the addition of a store on the west side of Phase 1 of the Villages of Hayti development along Grant Street, per BLK South. The Dooleys believe the dietary data from this next Edible Atlas study could prove the impact a grocery store has on a neighborhood’s health and hopefully secure funding.
“It takes research and hard data to sometimes convince folks with deep pockets to invest and put money in something that’s meaningful like this,” Erin said. Kendall Dooley also said it would be especially helpful to have that concrete evidence from Edible Atlas as they apply for grants.
Kirtley told the INDY that Edible Atlas began collecting neighborhood samples in October 2025 and started testing them later that year. The team will assess 20 to 24 Durham neighborhoods over the course of the study, with a mix of “low-, medium-, and high median-income” areas. They have not released the names of specific neighborhoods, pending ongoing engagement with residents about what information they would like to make public.
The funding for their Durham project ceases in December, which is around the time researchers aim to compile their findings and publish, Kirtley said. Edible Atlas is also working on producing an online summary dashboard, where the public will be able to access the information in an engaging way.
She also said the Duke lab believes it “ought to benefit the community that helps sustain our work in so many ways.” This is why they’re looking for funding to support future studies based on which trends the Durham community wants them to track—whether dietary, health conditions, or otherwise.
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