Development of a Portable, Biochar-Based Electrochemical PFAS Sensing Device to Protect Rural Water Resources

Per and polyfluorinated alkyl substances (PFAS) are chemically and biologically resistant organiccompounds that are persistent bioaccumulative and highly toxic. Owing to their widespreadcontamination of public drinking water supplies on June 21 2022 the US EnvironmentalProtection Agency announced new interim lifetime drinking water health advisories of 0.004nanograms per liter and 0.02 nanograms per liter for perfluorooctanoic acid (PFOA) andperfluorooctane sulfonate (PFOS) respectively. Beyond direct human consumption of PFAS- contaminated drinking water the use of PFAS-impacted water resources used to meet livestockdrinking water demands has led to numerous cases of agricultural product contamination (e.g.tainted dairy products) as well as growing public concern over fish meat and poultry quality.Similarly continued use of PFAS-impacted irrigation water has increased contamination of ruralpublic drinking water supplies and soil quality further exacerbating human exposure to these toxicpollutants. The objective of the STTR Phase I research proposal is to develop a biochar-basedelectrochemical device for the detection of PFAS. This portable device can utilize electrochemicalimpedance spectroscopic measurements to quantify PFOA/PFOS at picomolar concentrations ingroundwater surface water and reclaimed wastewater. The applied biochar is produced from ligninan abundant aromatic macromolecule component in biomass such as agricultural and forestryresidues. Ensuring the availability of high-quality water resources supports both public health andthe economic livelihood of rural communities.