A recent study led by Noemi Gavino-Lopez, a UNC SRP trainee and MS candidate in the UNC Gillings School of Global Public Health, highlighted the environmental injustice of toxic metals in private well water in NC. Inspired by the publication of the NCWELL database, which documented high levels of arsenic (As), manganese (Mn), cadmium (Cd) and lead (Pb) in private wells in NC, Gavino-Lopez wondered whether the exposure levels differed by social and economic factors across the state.
“Taking classes such as Environmental Health Issues and Systems Biology in Environmental Health informed my understanding of how environmental injustice shapes which populations are on private well water and who is most vulnerable,” stated Gavino-Lopez.
She specifically mentioned learning about the practice of municipal underbounding, or the deliberate unwillingness of a nearby city or town to annex an area and thus be required to supply water lines and sewer services, often resulting in peri-urban Black, Indigenous and People of Color (BIPOC) communities disproportionately relying on well water, as impacting her understanding of this issue.
The cost of testing—which can range from $35-250 USD—and treatment of well water, which can cost hundreds to thousands of dollars, can be a barrier for many low-income families. Equipped with this new understanding, Gavino-Lopez enlisted the support of Lauren Eaves, PhD, former UNC SRP trainee and current research scientist with the UNC Institute of Environmental Health Solutions (IEHS), and Rebecca Fry, PhD, SRP and IEHS director, to develop new Toxic Metal Environmental Justice Indices (TM-EJI) for NC.
The team used the US EPA’s framework for developing a nationwide Environmental Justice Index, which combines a demographic index value and environmental exposure, to create TM-EJIs for each census tract in NC.
The environmental exposure for the TM-EJIs was the number of well water tests reports above the EPA MCL for As and Cd, SMCL for Mn, or action level for Pb. The demographic value for each tract was the proportion of BIPOC and low-income households compared to the state’s overall minority and low-income population.
Analysis of the TM-EJI values across the state allowed Gavino-Lopez to identify census tracts with high levels of metal contamination and higher proportions of low-income and minority communities than the state overall.
“Most of the positive TM-EJI tracts are located in the eastern region of the state, especially for Pb and Mn, a region where the average poverty rate is higher than the rest of the state,” said Eaves.
When looking at toxic metals alone, not in combination with EJ-factors, the eastern part of the state may not be highlighted for well water user resources and support. “The TM-EJIs give researchers and state/county public health agencies a new data-driven tool to identify regions at risk of chemical and nonchemical stressors,” asserted Gavino-Lopez.
Future proposed research includes analyzing the TM-EJIs to see how these data relate to specific health outcomes in North Carolina, such as preterm birth, and integrating them in the NC ENVIROSCAN online mapping tool.
“The most impactful aspect of this project was realizing that a basic necessity like drinking water can be compromised for millions of people in the US,” reflected Gavino-Lopez. She will graduate in May with her MS from the Department of Environmental Sciences and Engineering and plans to pursue a career that allows her to continue to make advancements in public health.