RAPID ENZYMATIC DETECTION OF FECAL POLLUTION

Field vials were carried out using a 1-hour fluorimetric assay of beta -D-galactosidase activity alongside conventional membrane filtration t o detect faecal coliforms in beachwater samples. The ultimate aim of t he study was to test the reliability of the assay with a view to its u se in the field to assess the compliance of coastal bathing waters wit h the guideline concentrations. The assay had a 99% success rate at de tecting pass/fail at 300 faecal coliforms per 100 ml, using a threshol d fluorescence of 60.3 nM, A good correlation (r = 0.90) between faeca l coliform concentration and fluorescence assay results was obtained. The assay provides a rapid, simple and inexpensive method for the dete ction of sewage pollution in marine waters, and with the aid of portab le instrumentation, it may be performed in the field, allowing real ti me monitoring of water quality. Copyright (C) 1996 IAWQ.