FIBEROPTIC LASER-INDUCED FLUORESCENCE PROBE FOR THE DETECTION OF ENVIRONMENTAL-POLLUTANTS

Laser-induced fluorescence (LIF) spectroscopy in combination with fibe r optics is shown to be a powerful tool for qualitative and quantitati ve diagnostics of environmental pollutants in water and soil. Time-int egrated data accumulation of the LIF signals in early and late time wi ndows with respect to the excitation pulse simplifies the method so th at it becomes attractive for practical applications. Results from fiel d measurements are reported, as oil contaminations under a gas station and in an industrial sewer system are investigated. A KrF-excimer las er and a hydrogen Raman shifter can be applied for multiwavelength exc itation. This allows a discrimination between benzene, toluene, xylene , and ethylbenzene aromatics and polycyclic aromatic hydrocarbon molec ules in the samples under investigation. For a rough theoretical appro ach, a computer simulation is developed to describe the experimental r esults.