| Environmental surveillance is one of the major applications of analytical chemistry. Development of environmental surveillance systems is becoming increasingly important especially to achieve better understanding of the current environmental problems. Since most applications of analytical chemistry for environmental monitoring and protection involve trace determinations, reliable, highly sensitive and selective, as well as precise and accurate methods are required. The objective of this work was to develop field analysis methods (FAMs) based on electrochemical techniques for on-site environmental surveillance.;Efforts have been focused on the use of stripping analysis for the determination of trace metals and trace organic pollutants. Adsorptive Stripping Voltammetry and Constant Current Stripping Potentiometry are potentially useful for measuring such pollutants. The following metal-complexes, inorganic, and organic compounds have been determined successfully using both methods: uranyl-cupferron, thorium-cupferron, aluminum-cupferron, bismuth-cupferron, chromium-DTPA, nitrite, formaldehyde, polychlorinated biphenyls, explosives and nitro aromatics, and azodyes. Sample applications include surface water, ground water, and soil.;New methods and instrumentation have been investigated. For example, the use of mercury film and chemically modified electrodes as a remote sensing element for a target contaminant has been examined. A single use, disposable sensor has been developed for stripping voltammetry and potentiometry. Finally, readily automated systems based on both non-flow and flow-through stripping voltammetry have been investigated. The systems have been tested successfully for on-line monitoring of uranium, chromium, lead and cadmium, and nitrite.;Overall, the present work describes the attractive characteristics of electrochemical techniques for the development of reliable field analysis methods. The significant contributions of such techniques, namely stripping analysis, in environmental monitoring and management programs have been field-tested successfully. Not only can the techniques field screen a great deal of environmental samples, but they may also provide somewhat extensive information on the samples with relatively short analytical time. Though they may appear to be highly practical surveillance tools, electrochemical-based field analysis methods still allow sufficient room for improvements. |
