Use of Fish in the Detection of Contaminants in Water Supplies

THE manufacture and use of synthetic organic chemicals, some of which are highly toxic, have greatly increased. The possibility exists that some of these toxic chemicals may enter surface or ground water supplies. Such contaminants may come from pesticide applications, fish management operations, industrial wastes inadvertently or accidentally released, or other activities. Also, through acts of sabotage or in actual warfare, water supplies may be intentionally contaminated with highly toxic chemicals or biologic agents. Many of the potentially hazardous agents might not be removed by conventional water treatment processes and are not readily detectable by taste, odor, color, or ordinary chemical techniques. Fish are very sensitive to many of these contaminants in concentrations below levels considered harmful to humans and other animals. Live fish can be used in an inexpensive continuous monitoring system for rapidly detecting many of these toxicants. Such a system is described in this report. After initial detection, the physiologic reactions of the fish and the relationship between the reaction time and the concentration may be helpful in identifying the type and concentration of the toxicant; however, other methods may be needed to do this.