Moderne voltammetrische Verfahren in der Spurechemie toxischer Metalle in Trinkwasser, Regen‐ und Meerwasser

Abstract

AbstractModern voltammetric methods in trace chemistry of toxic metals in drinking water, rainwater and seawater. In environmental research and protection, toxic metals (particularly Cd, Pb and Hg) are becoming increasingly significant owing their biological nondegradability and the chronic toxicity resulting from their accumulation in vital organs of man. Aquatic systems, such as the sea, inland waters, drinking water, rainwater etc., are important stages in the biogeochemical cycle. Although the dissolved levels are usually in the trace range of μg/1 to ng/1 they still remain significant, because their entry into the food chain and interactions with suspended particulates and sedimnts largely occur via the dissolved state. General comparative considerations suggest modern voltammetric methods, particularly differential pulse stripping voltammetry (DPSV), to be the most promising choice for the determination and characterization of dissolved toxic heavy metal traces. Voltammetry combines extreme sensitivity with high inherent reliability, good precision, scope for simultaneous determination of several metals and modest costs. Moreover, due to its substance specificity, voltammetry permits identification and physicochemical characterization of dissolved complexes and chelates. The striking and comprehensive scope of voltammetry in trace metal chemistry of aquatic ecosystems is illustrated by examples from drinking water control, investigations on rainwater, extended studies in European coastal waters and the oceans, and by fundamental work on the occurrence and behaviour of toxic trace metal species in the sea.