Trace element distribution in seven mollusc species from Saronikos Gulf

Abstract

        The interest for the knowledge of the trace element content in the living organisms in recent years stems from the fact that certain elements play an important role in various physiological functions. Furthermore, the gra­dually increasing environmental pollution, resulting from industrial, domestic and radioactive waste disposal to the sea, dictates the necessity for a detailed study of the marine environment in order to protect the ecosystem and man.

        This work is concerned with the study of the trace element distribution in the whole bodies and individual organs of seven mollusc species from the Saronikos Gulf. The mollusc species Mytilus galloprovincialis, Meretrix chionae, Ostrea edulis, Venus verrucosa, Ensis ensis, Tapes decussatus, Glycymeris glycymeris have been selected because they are common in the Greek sea and they consist the pathway in the food chain between the lower marine organisms and the man.

        Modern analytical methods such as neutron activation analysis and atomic absorption spectroscopy were used for the detection and determination of the elements. The following elements were determined: As, Sb, Hg, Cu, Zn, Mn, Sr, Ba, Eu, Co, Cr, V, Au, Ni, Mg, Mo and Cs. The elements La, Ce, Sm, Gd, Tb, Ho, Er, Yb, Lu, Ga and Sc could not be detected. These elements have been chosen for the following reasons: Pollution effects, correspondence of these stable isotopes to the hazardous fission products of waste disposal radio­nuclides and biological importance.

        To find the distribution of these elements, determination was carried out on various parts of each organism and on each whole body.

       Concentration factors of the above elements have been found for the seven mollusc species by analysing the environmental water.

       Discussion on the results is made in the light of the distribution of the elements in the individual organs of each organism, and the variation in accumulation of the elements in the corresponding organs of the seven species. On the basis of the concentration factors, some species identified as «bioindicators» for the determined trace elements are given.