It is widely documented that fecal contamination of public beaches caused by sewage overflow is both dangerous for swimmers and costly for state and local economies.
Current methods to detect Escherichia coli, a bacterium highly indicative of the presence of fecal matter in water, typically require 24-48 hours to produce a result. A new, accurate, and economical sensor-based device capable of measuring E. coli levels in water samples in less than 1-8 hours could serve as a valuable early warning tool and is described in an article in Environmental Engineering Science, a peer-reviewed journal published by Mary Ann Liebert, Inc. (http://www.liebertpub.com). The article is available online at http://www.liebertpub.com/mcontent/files/EES-2011-0148-Nijak_5P.pdf
The article provides a detailed description of the autonomous, wireless, in-situ (AWISS), battery-powered device, which contains a prototype optical sensor that can measure changes in fluorescence intensity in a water sample. In the presence of E. coli bacteria an enzymatic reaction will cause an increase in fluorescence. The AWISS can detect high concentrations of bacteria in less than 1 hour and lower concentrations in less than 8 hours.
"Pathogens in the aquatic environment pose significant human and ecological health risks. The work of Professor Talley and his colleagues in developing a remote sensing instrument to detect and transmit pathogen water quality information is a major advance in helping safeguard human health," says Domenico Grasso, PhD, Editor-in-Chief and Vice President for Research, Dean of the Graduate College, University of Vermont (Burlington).