Non-elastic scattering of laser light by molecules manifests itself in characteristic fluorescence spectra and unique Raman scattered lines. Therefore, pollutants in water can be identified, and their concentration deduced, by remotely detecting and analysing such spectral signals. Spectral signatures of some samples, commonly encountered as water pollutants, are recorded and analysed. The methodologies, the present status and the future prospect of remote monitoring of pollution in surface waters and real-time non-invasive detection of pollution for the water and waste-water process control are reviewed in this article.
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