Optical sensing technologies for water contaminant detection: A comprehensive review

Water pollution is a major global issue that affects living organisms and poses a serious threat to future generations. As the demand for rapid and efficient detection of water contaminants increases, various analytical methods are being explored. Among these methods, optical methods, including colorimetric and spectroscopic techniques, have emerged as transformative approaches for the rapid detection of pollutants at extraordinarily low concentrations. Moreover, their compatibility with portable devices make them particularly suitable for monitoring water quality in remote or resource-limited areas. This review examines the role of optical devices in pollutant detection; discusses their operational principles, pros, and cons; and is supported by relevant examples. It also highlights recent advancements, future challenges, and recommendations for further development in this field.