Paper-Based Electroanalysis for Emerging Pollutant Detection.

Over the past two decades, the pollution lexicon has expanded beyond nutrients, hydrocarbons, and heavy metals to include emerging pollutants (EPs) and emerging contaminants (ECs), which now pose a critical challenge to environmental monitoring. Although, the conventional techniques are accurate and sensitive but often impractical for rapid, on-site monitoring. In response, a new wave of innovation has emerged to redefine environmental sensing through the development of paper-based electrochemical analytical devices (ePADs) which is a convergence of green chemistry, flexible electronics, and smart design. At the heart of their effectiveness lies in cellulose materials which depends on renewability, biodegradability, capillarity, and flexibility enable effective, low impact ePADs for passive fluid handling and microfluidics. Advances in 3D origami-based ePADs enable multi-analyte sensing, and, when paired with green manufacturing and smartphone-linked, low-power electronics, deliver real-time, cloud-ready data. Achieving widespread, sustainable deployment for decentralized pollution monitoring will require standardized validation, scalable manufacturing, and collaboration across scientific, technological, and policy domains. Looking forward, more than a replacement for conventional techniques, ePADs invite us to rethink our relationship with the environment. It signals a new contract between innovation and the planet-one in which analytical performance is inseparable from ecological responsibility. Each cellulose channel and fold demonstrates that high-precision sensing can be lightweight, biodegradable, and accessible. In this vision, smarter technology is also gentler, delivering cleaner water, healthier communities, and a more resilient Earth.