ABSTRACT
In the brief history of marine environmental toxicology, most research has been media oriented. A great deal of scientific and regulatory effort in aquatic toxicology has concentrated on characterizing the toxic effects in the water column environment resulting from contaminants of terrestrial origin. This chapter discusses chemical, physical, and biological processes that result in the release and transport of contaminants from sediments into the water column. It reviews the toxicological effects that have been observed during field surveys, laboratory, in situ organism testing, and microcosm/mesocosm studies. The chemical form of a pollutant determines its potential bioavailability to marine organisms. Currently, the environmental partitioning behavior of nonionic organic contaminant is the best understood of any class of organic chemical. The fate of transition metals in aquatic systems also is a function of several geochemical processes. The significance of microorganisms in aquatic ecosystems is well documented and includes mediation of the cycling of many elements and compounds.
