Using higher organisms in biological early warning systems for real-time toxicity detection

Many biological early warning systems (BEWS) have been developed in recent years that evaluate the physiological and behavioral responses of whole org anisms to water quality. Using a fish ventilatory monitoring system develop ed at the US Army Centre for Environmental Health Research as an example, w e illustrate the operation of a BEWS at a groundwater treatment facility. D uring a recent 12-month period, the fish ventilatory system was operational for 99%, of the time that the treatment facility was on-line. Effluent-exp osed fish responded as a group about 2.8% of the time. While some events we re due to equipment problems or non-toxic water quality variations, the fis h system did indicate effluent anomalies that were subsequently identified and corrected. The fish monitoring BEWS increased treatment facility engine ers' awareness of effluent quality and provided an extra measure of assuran ce to regulators and the public. Many operational and practical considerati ons for whole organism BEWS are similar to those for cell- or tissue-based biosensors. An effective biomonitoring system may need to integrate the res ponses of several biological and chemical sensors to achieve desired operat ional goals. Future development of an 'electronic canary', analogous to the original canary in the coal mine, could draw upon advances in signal proce ssing and communication to establish a network of sensors in a watershed an d to provide useful real-time information on water quality. (C) 2001 Elsevi er Science B.V. All rights reserved.