Smartphone-enabled field monitoring tool for rapid hexavalent chromium detection in water.

Chromium contamination of soil and water is a serious environmental and public health concern as the hexavalent form of chromium [Cr(VI)] is readily soluble in water and is a confirmed carcinogen. There is an imminent need for a robust, low-cost, and simple analytical technique to facilitate in situ monitoring of Cr(VI) in water. Current quantitative methods of Cr(VI) detection are largely laboratory-based, time-consuming, expensive, and require training for implementation.