The particular behavior of trace metals in the environment is determined by their specific physico-chemical form rather than by their total concentration. The introduction of atomic absorption spectrometry has lead to a plethora of scientific papers and reports in which metal concentrations in the environment are only reported as total concentrations. Only recently has the need for improved knowledge on the various forms and bioavailability of metals been realised. Considerable research effort is now devoted to measuring the concentrations of trace metals in surface waters. Efforts are made...

Hazard assessment of a compound (xenobiotic) discharged to the aquatic environment requires data on both exposure and effects to various components of the ecosystem. The multitude of ecological gradients in the Baltic Sea is used as a background example for discussing the complexity of the issue and the need for new approaches. Therefore, this book attempts to go beyond the simplistic, standardized short-term laboratory tests traditionally used as a basis for hazard assessment of chemicals, and gives strong emphasis to the interpretation of ecotoxicological data in their real, ecological...