Community-Wide Monitoring of Lead in Drinking Water Distribution Systems Using Hand-Held Voltammetric Sensors and Geographic Information Systems

Lead (Pb²⁺) contamination in drinking water remains a critical public health concern, particularly for children, due to lead pipes and plumbing in many water systems. Conventional Pb²⁺ detection methods, such as ICP-MS and AAS, are costly, time-intensive, and require specialized personnel. In this study, we developed and utilized a portable voltammetric Pb²⁺ detection system, the E-Tongue, which features a mercury-free, gold nanostar-modified screen-printed carbon electrode, and nontoxic buffer reagents (0.1 M sodium acetate, 0.1 mM potassium ferrocyanide, pH 4.5). The E-Tongue provides Pb²⁺ detection within 5 min with a method detection limit of 1.6 ppb and a wide linear range of 5-200 ppb. Results demonstrated the E-Tongue's ability to detect Pb²⁺ above the EPA action level (10 ppb), even in high Cu²⁺ conditions (up to 1.3 ppm), with Pb²⁺ recovery of 84-105% and RSD < 10%. The E-Tongue's color-coded and quantitative feedback enables nonexperts to test tap water and share data, facilitating community-driven monitoring and intervention strategies. Additionally, spatial analysis revealed that Andover had the most alkaline and conductive tap water, while Lawrence exhibited neutral water on average. The E-Tongue empowers communities, demonstrating the potential of participatory approaches for lead detection and mitigation in water networks.