Biomonitoring of heavy metals and their species in the marine environment: the contribution of atomic absorption spectroscopy and inductively coupled plasma spectroscopy

This review focuses on theoretical and practical aspects of the biological monitoring of heavy metals in the marine environment, covering the analyses of seawater, sediment and marine biota as the materials of study for a full characterization of the pollution degree of the geographical area investigated. The biomonitoring is a typical analytical process. All the steps involved are described in detail: from the selection of the biological indicator and the design of the sampling strategy to accomplish the objectives of the biomonitoring study to the statistical evaluation of the results are thoroughly discussed. Emphasis on the role of atomic spectrometries in pollution diagnosis is given to demonstrate the potentiality of these technical tools at the present time to achieve the lowest detection limits required for the analysis of trace metals in the environment. Even when analysis of total amount of heavy metals is still of concern in marine environmental assessment speciation analysis is developing as a new field for research in ecotoxicological studies and for prevention of pollution risks to all the members of the aquatic ecosystem. Heavy metals speciation is highlighted in a separate section of this review. Description of the chromatographic and non chromatographic techniques coupled to AAS and ICP detectors employed for the analyses of organometallic compounds, inorganic forms and redox species of heavy metals in environmental and biological samples is also addressed. The relevance of the biomonitoring of heavy metals and their species in the marine environment directed to record and evaluate analytical data is to provide a powerful body of information to help national and international organizations interested in the protection of natural resources and public health. For example, the accepted concentration of tributyltin (TBT),, an environmental contaminant, in waters is regulated in the European Community from data provided by monitoring programmes. Thus, a limit value of 10 ng. L-1 for TBT in natural waters has been stated in the Dutch legislation.